arch/um/os-Linux/registers.c

   1 /*
   2  * Copyright (C) 2004 PathScale, Inc
   3  * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   4  * Licensed under the GPL
   5  */
   6
   7 #include <errno.h>
   8 #include <string.h>
   9 #include <sys/ptrace.h>
  10 #include "sysdep/ptrace.h"
  11
  12 int save_registers(int pid, struct uml_pt_regs *regs)
  13 {
  14         int err;
  15
  16         err = ptrace(PTRACE_GETREGS, pid, 0, regs->gp);
  17         if (err < 0)
  18                 return -errno;
  19         return 0;
  20 }
  21
  22 int restore_registers(int pid, struct uml_pt_regs *regs)
  23 {
  24         int err;
  25
  26         err = ptrace(PTRACE_SETREGS, pid, 0, regs->gp);
  27         if (err < 0)
  28                 return -errno;
  29         return 0;
  30 }
  31
  32 /* This is set once at boot time and not changed thereafter */
  33
  34 static unsigned long exec_regs[MAX_REG_NR];
  35
  36 int init_registers(int pid)
  37 {
  38         int err;
  39
  40         err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
  41         if (err < 0)
  42                 return -errno;
  43
  44         arch_init_registers(pid);
  45         return 0;
  46 }
  47
  48 void get_safe_registers(unsigned long *regs)
  49 {
  50         memcpy(regs, exec_regs, sizeof(exec_regs));
  51 }