arch/um/os-Linux/sys-x86_64/registers.c

   1 /*
   2  * Copyright (C) 2004 PathScale, Inc
   3  * Licensed under the GPL
   4  */
   5
   6 #include <errno.h>
   7 #include <string.h>
   8 #include "ptrace_user.h"
   9 #include "uml-config.h"
  10 #include "skas_ptregs.h"
  11 #include "registers.h"
  12 #include "longjmp.h"
  13 #include "user.h"
  14
  15 /* These are set once at boot time and not changed thereafter */
  16
  17 static unsigned long exec_regs[HOST_FRAME_SIZE];
  18 static unsigned long exec_fp_regs[HOST_FP_SIZE];
  19
  20 void init_thread_registers(union uml_pt_regs *to)
  21 {
  22         memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
  23         memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
  24 }
  25
  26 static int move_registers(int pid, int int_op, int fp_op,
  27                           union uml_pt_regs *regs)
  28 {
  29         if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
  30                 return -errno;
  31
  32         if(ptrace(fp_op, pid, 0, regs->skas.fp) < 0)
  33                 return -errno;
  34
  35         return 0;
  36 }
  37
  38 void save_registers(int pid, union uml_pt_regs *regs)
  39 {
  40         int err;
  41
  42         err = move_registers(pid, PTRACE_GETREGS, PTRACE_GETFPREGS, regs);
  43         if(err)
  44                 panic("save_registers - saving registers failed, errno = %d\n",
  45                       -err);
  46 }
  47
  48 void restore_registers(int pid, union uml_pt_regs *regs)
  49 {
  50         int err;
  51
  52         err = move_registers(pid, PTRACE_SETREGS, PTRACE_SETFPREGS, regs);
  53         if(err)
  54                 panic("restore_registers - saving registers failed, "
  55                       "errno = %d\n", -err);
  56 }
  57
  58 void init_registers(int pid)
  59 {
  60         int err;
  61
  62         err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
  63         if(err)
  64                 panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
  65                       errno);
  66
  67         err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
  68         if(err)
  69                 panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
  70                       errno);
  71 }
  72
  73 void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
  74 {
  75         memcpy(regs, exec_regs, HOST_FRAME_SIZE * sizeof(unsigned long));
  76         if(fp_regs != NULL)
  77                 memcpy(fp_regs, exec_fp_regs,
  78                        HOST_FP_SIZE * sizeof(unsigned long));
  79 }
  80
  81 unsigned long get_thread_reg(int reg, jmp_buf *buf)
  82 {
  83         switch(reg){
  84         case RIP: return buf[0]->__rip;
  85         case RSP: return buf[0]->__rsp;
  86         case RBP: return buf[0]->__rbp;
  87         default:
  88                 printk("get_thread_regs - unknown register %d\n", reg);
  89                 return 0;
  90         }
  91 }