arch/powerpc/kernel/syscalls.c

   1 /*
   2  *  Implementation of various system calls for Linux/PowerPC
   3  *
   4  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   5  *
   6  * Derived from "arch/i386/kernel/sys_i386.c"
   7  * Adapted from the i386 version by Gary Thomas
   8  * Modified by Cort Dougan (cort@cs.nmt.edu)
   9  * and Paul Mackerras (paulus@cs.anu.edu.au).
  10  *
  11  * This file contains various random system calls that
  12  * have a non-standard calling sequence on the Linux/PPC
  13  * platform.
  14  *
  15  *  This program is free software; you can redistribute it and/or
  16  *  modify it under the terms of the GNU General Public License
  17  *  as published by the Free Software Foundation; either version
  18  *  2 of the License, or (at your option) any later version.
  19  *
  20  */
  21
  22 #include <linux/errno.h>
  23 #include <linux/sched.h>
  24 #include <linux/syscalls.h>
  25 #include <linux/mm.h>
  26 #include <linux/fs.h>
  27 #include <linux/smp.h>
  28 #include <linux/sem.h>
  29 #include <linux/msg.h>
  30 #include <linux/shm.h>
  31 #include <linux/stat.h>
  32 #include <linux/mman.h>
  33 #include <linux/sys.h>
  34 #include <linux/ipc.h>
  35 #include <linux/utsname.h>
  36 #include <linux/file.h>
  37 #include <linux/personality.h>
  38
  39 #include <asm/uaccess.h>
  40 #include <asm/syscalls.h>
  41 #include <asm/time.h>
  42 #include <asm/unistd.h>
  43 #include <asm/asm-prototypes.h>
  44
  45 static inline unsigned long do_mmap2(unsigned long addr, size_t len,
  46                         unsigned long prot, unsigned long flags,
  47                         unsigned long fd, unsigned long off, int shift)
  48 {
  49         unsigned long ret = -EINVAL;
  50
  51         if (!arch_validate_prot(prot))
  52                 goto out;
  53
  54         if (shift) {
  55                 if (off & ((1 << shift) - 1))
  56                         goto out;
  57                 off >>= shift;
  58         }
  59
  60         ret = sys_mmap_pgoff(addr, len, prot, flags, fd, off);
  61 out:
  62         return ret;
  63 }
  64
  65 unsigned long sys_mmap2(unsigned long addr, size_t len,
  66                         unsigned long prot, unsigned long flags,
  67                         unsigned long fd, unsigned long pgoff)
  68 {
  69         return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
  70 }
  71
  72 unsigned long sys_mmap(unsigned long addr, size_t len,
  73                        unsigned long prot, unsigned long flags,
  74                        unsigned long fd, off_t offset)
  75 {
  76         return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
  77 }
  78
  79 #ifdef CONFIG_PPC32
  80 /*
  81  * Due to some executables calling the wrong select we sometimes
  82  * get wrong args.  This determines how the args are being passed
  83  * (a single ptr to them all args passed) then calls
  84  * sys_select() with the appropriate args. -- Cort
  85  */
  86 int
  87 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
  88 {
  89         if ( (unsigned long)n >= 4096 )
  90         {
  91                 unsigned long __user *buffer = (unsigned long __user *)n;
  92                 if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
  93                     || __get_user(n, buffer)
  94                     || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
  95                     || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
  96                     || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
  97                     || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
  98                         return -EFAULT;
  99         }
 100         return sys_select(n, inp, outp, exp, tvp);
 101 }
 102 #endif
 103
 104 #ifdef CONFIG_PPC64
 105 long ppc64_personality(unsigned long personality)
 106 {
 107         long ret;
 108
 109         if (personality(current->personality) == PER_LINUX32
 110             && personality(personality) == PER_LINUX)
 111                 personality = (personality & ~PER_MASK) | PER_LINUX32;
 112         ret = sys_personality(personality);
 113         if (personality(ret) == PER_LINUX32)
 114                 ret = (ret & ~PER_MASK) | PER_LINUX;
 115         return ret;
 116 }
 117 #endif
 118
 119 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
 120                       u32 len_high, u32 len_low)
 121 {
 122         return sys_fadvise64(fd, (u64)offset_high << 32 | offset_low,
 123                              (u64)len_high << 32 | len_low, advice);
 124 }
 125
 126 long sys_switch_endian(void)
 127 {
 128         struct thread_info *ti;
 129
 130         current->thread.regs->msr ^= MSR_LE;
 131
 132         /*
 133          * Set TIF_RESTOREALL so that r3 isn't clobbered on return to
 134          * userspace. That also has the effect of restoring the non-volatile
 135          * GPRs, so we saved them on the way in here.
 136          */
 137         ti = current_thread_info();
 138         ti->flags |= _TIF_RESTOREALL;
 139
 140         return 0;
 141 }