l4/pkg/plr/server/src/fault_handlers/debugging.h

   1 #pragma once
   2 /*
   3  * debugging.h --
   4  *
   5  *     Debugging interface
   6  *
   7  * (c) 2011-2013 Björn Döbel <doebel@os.inf.tu-dresden.de>,
   8  *     economic rights: Technische Universität Dresden (Germany)
   9  * This file is part of TUD:OS and distributed under the terms of the
  10  * GNU General Public License 2.
  11  * Please see the COPYING-GPL-2 file for details.
  12  */
  13
  14
  15 #include "../log"
  16 #include "../manager"
  17 #include "../app_loading"
  18
  19 class Breakpoint
  20 {
  21         enum {
  22                 BREAK_INSTRUCTION = 0xCC,
  23         };
  24
  25         l4_addr_t   _address;
  26         l4_umword_t _orig_code;
  27         unsigned    _refcnt;
  28
  29         public:
  30                 Breakpoint(l4_addr_t addr)
  31                         : _address(addr), _orig_code(0), _refcnt(0)
  32                 { }
  33
  34
  35                 ~Breakpoint()
  36                 { }
  37
  38
  39                 void activate(Romain::App_instance *i, Romain::App_model *m)
  40                 {
  41                         ++_refcnt;
  42                         l4_addr_t local = m->rm()->remote_to_local(address(), i->id());
  43                         DEBUG() << "Setting BP @ 0x" << std::hex << address()
  44                                 << " -> local 0x" << local;
  45                         _orig_code = *(l4_umword_t*)local;
  46                         *(unsigned char*)local = BREAK_INSTRUCTION;
  47                         DEBUG() << "addr @ " << std::hex << &_address;
  48                 }
  49
  50
  51                 void deactivate(Romain::App_instance *i, Romain::App_model *m)
  52                 {
  53                         --_refcnt;
  54                         DEBUG() << "Deactivating bp @ " << std::hex << address()
  55                                 << " in instance " << i->id();
  56                         DEBUG() << "(addr == " << &_address << ")";
  57                         l4_addr_t local = m->rm()->remote_to_local(address(), i->id());
  58                         *(l4_umword_t*)local = _orig_code;
  59                 }
  60
  61
  62                 l4_addr_t address() { return _address; }
  63                 l4_umword_t orig()  { return _orig_code; }
  64                 unsigned refs() const { return _refcnt; }
  65
  66                 bool was_hit(Romain::App_thread *t)
  67                 {
  68                         return (t->vcpu()->r()->ip - 1) == _address;
  69                 }
  70 };