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        if (!arch_validate_prot(prot, addr))
  45                return -EINVAL;
  46
  47        if (!IS_ALIGNED(off, 1 << shift))
  48                return -EINVAL;
  49
  50        return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> shift);
  51}
  52
  53SYSCALL_DEFINE6(mmap2, unsigned long, addr, size_t, len,
  54                unsigned long, prot, unsigned long, flags,
  55                unsigned long, fd, unsigned long, pgoff)
  56{
  57        return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
  58}
  59
  60SYSCALL_DEFINE6(mmap, unsigned long, addr, size_t, len,
  61                unsigned long, prot, unsigned long, flags,
  62                unsigned long, fd, off_t, offset)
  63{
  64        return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
  65}
  66
  67#ifdef CONFIG_PPC32
  68/*
  69 * Due to some executables calling the wrong select we sometimes
  70 * get wrong args.  This determines how the args are being passed
  71 * (a single ptr to them all args passed) then calls
  72 * sys_select() with the appropriate args. -- Cort
  73 */
  74int
  75ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct __kernel_old_timeval __user *tvp)
  76{
  77        if ( (unsigned long)n >= 4096 )
  78                return sys_old_select((void __user *)n);
  79
  80        return sys_select(n, inp, outp, exp, tvp);
  81}
  82#endif
  83
  84#ifdef CONFIG_PPC64
  85long ppc64_personality(unsigned long personality)
  86{
  87        long ret;
  88
  89        if (personality(current->personality) == PER_LINUX32
  90            && personality(personality) == PER_LINUX)
  91                personality = (personality & ~PER_MASK) | PER_LINUX32;
  92        ret = sys_personality(personality);
  93        if (personality(ret) == PER_LINUX32)
  94                ret = (ret & ~PER_MASK) | PER_LINUX;
  95        return ret;
  96}
  97#endif
  98
  99long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
 100                      u32 len_high, u32 len_low)
 101{
 102        return ksys_fadvise64_64(fd, (u64)offset_high << 32 | offset_low,
 103                                 (u64)len_high << 32 | len_low, advice);
 104}
 105
 106SYSCALL_DEFINE0(switch_endian)
 107{
 108        struct thread_info *ti;
 109
 110        regs_set_return_msr(current->thread.regs,
 111                                current->thread.regs->msr ^ MSR_LE);
 112
 113        /*
 114         * Set TIF_RESTOREALL so that r3 isn't clobbered on return to
 115         * userspace. That also has the effect of restoring the non-volatile
 116         * GPRs, so we saved them on the way in here.
 117         */
 118        ti = current_thread_info();
 119        ti->flags |= _TIF_RESTOREALL;
 120
 121        return 0;
 122}
 123