Line data    Source code

       1             : /* Fetch live process registers from TID.
       2             :    Copyright (C) 2013 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             : 
       5             :    This file is free software; you can redistribute it and/or modify
       6             :    it under the terms of either
       7             : 
       8             :      * the GNU Lesser General Public License as published by the Free
       9             :        Software Foundation; either version 3 of the License, or (at
      10             :        your option) any later version
      11             : 
      12             :    or
      13             : 
      14             :      * the GNU General Public License as published by the Free
      15             :        Software Foundation; either version 2 of the License, or (at
      16             :        your option) any later version
      17             : 
      18             :    or both in parallel, as here.
      19             : 
      20             :    elfutils is distributed in the hope that it will be useful, but
      21             :    WITHOUT ANY WARRANTY; without even the implied warranty of
      22             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      23             :    General Public License for more details.
      24             : 
      25             :    You should have received copies of the GNU General Public License and
      26             :    the GNU Lesser General Public License along with this program.  If
      27             :    not, see <http://www.gnu.org/licenses/>.  */
      28             : 
      29             : #ifdef HAVE_CONFIG_H
      30             : # include <config.h>
      31             : #endif
      32             : 
      33             : #include "system.h"
      34             : #include <assert.h>
      35             : #if defined(__s390__) && defined(__linux__)
      36             : # include <sys/user.h>
      37             : # include <sys/ptrace.h>
      38             : # include <asm/ptrace.h>
      39             : #endif
      40             : 
      41             : #define BACKEND s390_
      42             : #include "libebl_CPU.h"
      43             : 
      44             : bool
      45           0 : s390_set_initial_registers_tid (pid_t tid __attribute__ ((unused)),
      46             :                           ebl_tid_registers_t *setfunc __attribute__ ((unused)),
      47             :                                 void *arg __attribute__ ((unused)))
      48             : {
      49             : #if !defined(__s390__) || !defined(__linux__)
      50           0 :   return false;
      51             : #else /* __s390__ */
      52             :   struct user user_regs;
      53             :   ptrace_area parea;
      54             :   parea.process_addr = (uintptr_t) &user_regs;
      55             :   parea.kernel_addr = 0;
      56             :   parea.len = sizeof (user_regs);
      57             :   if (ptrace (PTRACE_PEEKUSR_AREA, tid, &parea, NULL) != 0)
      58             :     return false;
      59             :   /* If we run as s390x we get the 64-bit registers of tid.
      60             :      But -m31 executable seems to use only the 32-bit parts of its
      61             :      registers so we ignore the upper half.  */
      62             :   Dwarf_Word dwarf_regs[16];
      63             :   for (unsigned u = 0; u < 16; u++)
      64             :     dwarf_regs[u] = user_regs.regs.gprs[u];
      65             :   if (! setfunc (0, 16, dwarf_regs, arg))
      66             :     return false;
      67             :   /* Avoid conversion double -> integer.  */
      68             :   eu_static_assert (sizeof user_regs.regs.fp_regs.fprs[0]
      69             :                     == sizeof dwarf_regs[0]);
      70             :   for (unsigned u = 0; u < 16; u++)
      71             :     {
      72             :       // Store the double bits as is in the Dwarf_Word without conversion.
      73             :       union
      74             :         {
      75             :           double d;
      76             :           Dwarf_Word w;
      77             :         } fpr = { .d = user_regs.regs.fp_regs.fprs[u] };
      78             :       dwarf_regs[u] = fpr.w;
      79             :     }
      80             : 
      81             :   if (! setfunc (16, 16, dwarf_regs, arg))
      82             :     return false;
      83             :   dwarf_regs[0] = user_regs.regs.psw.addr;
      84             :   return setfunc (-1, 1, dwarf_regs, arg);
      85             : #endif /* __s390__ */
      86             : }
      87             : 
      88             : void
      89          24 : s390_normalize_pc (Ebl *ebl __attribute__ ((unused)), Dwarf_Addr *pc)
      90             : {
      91          24 :   assert (ebl->class == ELFCLASS32);
      92             : 
      93             :   /* Clear S390 bit 31.  */
      94          24 :   *pc &= (1U << 31) - 1;
      95          24 : }