arch/um/sys-i386/syscalls.c

   1 /*
   2  * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/sched.h"
   7 #include "asm/mman.h"
   8 #include "asm/uaccess.h"
   9 #include "asm/unistd.h"
  10
  11 /*
  12  * Perform the select(nd, in, out, ex, tv) and mmap() system
  13  * calls. Linux/i386 didn't use to be able to handle more than
  14  * 4 system call parameters, so these system calls used a memory
  15  * block for parameter passing..
  16  */
  17
  18 struct mmap_arg_struct {
  19         unsigned long addr;
  20         unsigned long len;
  21         unsigned long prot;
  22         unsigned long flags;
  23         unsigned long fd;
  24         unsigned long offset;
  25 };
  26
  27 extern int old_mmap(unsigned long addr, unsigned long len,
  28                     unsigned long prot, unsigned long flags,
  29                     unsigned long fd, unsigned long offset);
  30
  31 int old_mmap_i386(struct mmap_arg_struct *arg)
  32 {
  33         struct mmap_arg_struct a;
  34         int err = -EFAULT;
  35
  36         if (copy_from_user(&a, arg, sizeof(a)))
  37                 goto out;
  38
  39         err = old_mmap(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
  40  out:
  41         return err;
  42 }
  43
  44 struct sel_arg_struct {
  45         unsigned long n;
  46         fd_set *inp, *outp, *exp;
  47         struct timeval *tvp;
  48 };
  49
  50 int old_select(struct sel_arg_struct *arg)
  51 {
  52         struct sel_arg_struct a;
  53
  54         if (copy_from_user(&a, arg, sizeof(a)))
  55                 return -EFAULT;
  56         /* sys_select() does the appropriate kernel locking */
  57         return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
  58 }
  59
  60 /* The i386 version skips reading from %esi, the fourth argument. So we must do
  61  * this, too.
  62  */
  63 int sys_clone(unsigned long clone_flags, unsigned long newsp, int *parent_tid,
  64               int unused, int *child_tid)
  65 {
  66         long ret;
  67
  68         /* XXX: normal arch do here this pass, and also pass the regs to
  69          * do_fork, instead of NULL. Currently the arch-independent code
  70          * ignores these values, while the UML code (actually it's
  71          * copy_thread) does the right thing. But this should change,
  72          probably. */
  73         /*if (!newsp)
  74                 newsp = UPT_SP(current->thread.regs);*/
  75         current->thread.forking = 1;
  76         ret = do_fork(clone_flags, newsp, NULL, 0, parent_tid, child_tid);
  77         current->thread.forking = 0;
  78         return(ret);
  79 }
  80
  81 /*
  82  * Overrides for Emacs so that we follow Linus's tabbing style.
  83  * Emacs will notice this stuff at the end of the file and automatically
  84  * adjust the settings for this buffer only.  This must remain at the end
  85  * of the file.
  86  * ---------------------------------------------------------------------------
  87  * Local variables:
  88  * c-file-style: "linux"
  89  * End:
  90  */