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
  39static inline long do_mmap2(unsigned long addr, size_t len,
  40                        unsigned long prot, unsigned long flags,
  41                        unsigned long fd, unsigned long off, int shift)
  42{
  43        if (!arch_validate_prot(prot, addr))
  44                return -EINVAL;
  45
  46        if (!IS_ALIGNED(off, 1 << shift))
  47                return -EINVAL;
  48
  49        return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> shift);
  50}
  51
  52SYSCALL_DEFINE6(mmap2, unsigned long, addr, size_t, len,
  53                unsigned long, prot, unsigned long, flags,
  54                unsigned long, fd, unsigned long, pgoff)
  55{
  56        return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
  57}
  58
  59SYSCALL_DEFINE6(mmap, unsigned long, addr, size_t, len,
  60                unsigned long, prot, unsigned long, flags,
  61                unsigned long, fd, off_t, offset)
  62{
  63        return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
  64}
  65
  66#ifdef CONFIG_PPC32
  67/*
  68 * Due to some executables calling the wrong select we sometimes
  69 * get wrong args.  This determines how the args are being passed
  70 * (a single ptr to them all args passed) then calls
  71 * sys_select() with the appropriate args. -- Cort
  72 */
  73int
  74ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct __kernel_old_timeval __user *tvp)
  75{
  76        if ((unsigned long)n >= 4096)
  77                return sys_old_select((void __user *)n);
  78
  79        return sys_select(n, inp, outp, exp, tvp);
  80}
  81#endif
  82
  83#ifdef CONFIG_PPC64
  84long ppc64_personality(unsigned long personality)
  85{
  86        long ret;
  87
  88        if (personality(current->personality) == PER_LINUX32
  89            && personality(personality) == PER_LINUX)
  90                personality = (personality & ~PER_MASK) | PER_LINUX32;
  91        ret = sys_personality(personality);
  92        if (personality(ret) == PER_LINUX32)
  93                ret = (ret & ~PER_MASK) | PER_LINUX;
  94        return ret;
  95}
  96#endif
  97
  98long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
  99                      u32 len_high, u32 len_low)
 100{
 101        return ksys_fadvise64_64(fd, (u64)offset_high << 32 | offset_low,
 102                                 (u64)len_high << 32 | len_low, advice);
 103}
 104
 105SYSCALL_DEFINE0(switch_endian)
 106{
 107        struct thread_info *ti;
 108
 109        regs_set_return_msr(current->thread.regs,
 110                                current->thread.regs->msr ^ MSR_LE);
 111
 112        /*
 113         * Set TIF_RESTOREALL so that r3 isn't clobbered on return to
 114         * userspace. That also has the effect of restoring the non-volatile
 115         * GPRs, so we saved them on the way in here.
 116         */
 117        ti = current_thread_info();
 118        ti->flags |= _TIF_RESTOREALL;
 119
 120        return 0;
 121}
 122