vm.c

这个是LINUX下的GDB调度工具的源码

  return EXTRACTED(pte_1, 56, 56);
}

STATIC_INLINE_VM\
(int)
om_pte_1_masked_rpn(unsigned_word pte_1)
{
  return MASKED(pte_1, 0, 51); /*RPN*/
}

STATIC_INLINE_VM\
(unsigned_word)
om_ea_api(unsigned_word ea)
{
  return EXTRACTED(ea, 36, 41);
}


/* Page and Segment table read/write operators, these need to still
   account for the PPC's XOR operation */

STATIC_INLINE_VM\
(unsigned_word)
om_read_word(om_map *map,
	     unsigned_word ra,
	     cpu *processor,
	     unsigned_word cia)
{
  if (WITH_XOR_ENDIAN)
    ra ^= map->xor[sizeof(instruction_word) - 1];
  return core_map_read_word(map->physical, ra, processor, cia);
}

STATIC_INLINE_VM\
(void)
om_write_word(om_map *map,
	      unsigned_word ra,
	      unsigned_word val,
	      cpu *processor,
	      unsigned_word cia)
{
  if (WITH_XOR_ENDIAN)
    ra ^= map->xor[sizeof(instruction_word) - 1];
  core_map_write_word(map->physical, ra, val, processor, cia);
}


/* Bring things into existance */

INLINE_VM\
(vm *)
vm_create(core *physical)
{
  vm *virtual;

  /* internal checks */
  if (nr_om_segment_tlb_entries
      != (1 << (om_segment_tlb_index_stop_bit
		- om_segment_tlb_index_start_bit + 1)))
    error("internal error - vm_create - problem with om_segment constants\n");
  if (nr_om_page_tlb_entries
      != (1 << (om_page_tlb_index_stop_bit
		- om_page_tlb_index_start_bit + 1)))
    error("internal error - vm_create - problem with om_page constants\n");

  /* create the new vm register file */
  virtual = ZALLOC(vm);

  /* set up core */
  virtual->physical = physical;

  /* set up the address decoders */
  virtual->instruction_map.translation.bat_registers = &virtual->ibats;
  virtual->instruction_map.translation.segment_tlb = &virtual->segment_tlb;
  virtual->instruction_map.translation.page_tlb = &virtual->instruction_tlb;
  virtual->instruction_map.translation.is_relocate = 0;
  virtual->instruction_map.translation.is_problem_state = 0;
  virtual->instruction_map.translation.physical = core_readable(physical);
  virtual->instruction_map.code = core_readable(physical);

  virtual->data_map.translation.bat_registers = &virtual->dbats;
  virtual->data_map.translation.segment_tlb = &virtual->segment_tlb;
  virtual->data_map.translation.page_tlb = &virtual->data_tlb;
  virtual->data_map.translation.is_relocate = 0;
  virtual->data_map.translation.is_problem_state = 0;
  virtual->data_map.translation.physical = core_readable(physical);
  virtual->data_map.read = core_readable(physical);
  virtual->data_map.write = core_writeable(physical);

  return virtual;
}


STATIC_INLINE_VM\
(om_bat *)
om_effective_to_bat(om_map *map,
		    unsigned_word ea)
{
  int curr_bat = 0;
  om_bats *bats = map->bat_registers;
  int nr_bats = bats->nr_valid_bat_registers;

  for (curr_bat = 0; curr_bat < nr_bats; curr_bat++) {
    om_bat *bat = bats->bat + curr_bat;
    if ((ea & bat->block_effective_page_index_mask)
	!= bat->block_effective_page_index)
      continue;
    return bat;
  }

  return NULL;
}


STATIC_INLINE_VM\
(om_segment_tlb_entry *)
om_effective_to_virtual(om_map *map, 
			unsigned_word ea,
			cpu *processor,
			unsigned_word cia)
{
  /* first try the segment tlb */
  om_segment_tlb_entry *segment_tlb_entry = (map->segment_tlb->entry
					     + om_segment_tlb_index(ea));

#if (WITH_TARGET_WORD_BITSIZE == 32)
  TRACE(trace_vm, ("ea=0x%lx - sr[%ld] - masked-vsid=0x%lx va=0x%lx%07lx\n",
		   (unsigned long)ea,
		   (long)om_segment_tlb_index(ea),
		   (unsigned long)segment_tlb_entry->masked_virtual_segment_id, 
		   (unsigned long)EXTRACTED32(segment_tlb_entry->masked_virtual_segment_id, 31-6-24+1, 31-6),
		   (unsigned long)EXTRACTED32(ea, 4, 31)));
  return segment_tlb_entry;
#endif

#if (WITH_TARGET_WORD_BITSIZE == 64)
  if (segment_tlb_entry->is_valid
      && (segment_tlb_entry->masked_effective_segment_id == MASKED(ea, 0, 35))) {
    error("fixme - is there a need to update any bits\n");
    return segment_tlb_entry;
  }

  /* drats, segment tlb missed */
  {
    unsigned_word segment_id_hash = ea;
    int current_hash = 0;
    for (current_hash = 0; current_hash < 2; current_hash += 1) {
      unsigned_word segment_table_entry_group =
	(map->real_address_of_segment_table
	 | (MASKED64(segment_id_hash, 31, 35) >> (56-35)));
      unsigned_word segment_table_entry;
      for (segment_table_entry = segment_table_entry_group;
	   segment_table_entry < (segment_table_entry_group
				  + sizeof_segment_table_entry_group);
	   segment_table_entry += sizeof_segment_table_entry) {
	/* byte order? */
	unsigned_word segment_table_entry_dword_0 =
	  om_read_word(map->physical, segment_table_entry, processor, cia);
	unsigned_word segment_table_entry_dword_1 =
	  om_read_word(map->physical, segment_table_entry + 8,
		       processor, cia);
	int is_valid = MASKED64(segment_table_entry_dword_0, 56, 56) != 0;
	unsigned_word masked_effective_segment_id =
	  MASKED64(segment_table_entry_dword_0, 0, 35);
	if (is_valid && masked_effective_segment_id == MASKED64(ea, 0, 35)) {
	  /* don't permit some things */
	  if (MASKED64(segment_table_entry_dword_0, 57, 57))
	    error("om_effective_to_virtual() - T=1 in STE not supported\n");
	  /* update segment tlb */
	  segment_tlb_entry->is_valid = is_valid;
	  segment_tlb_entry->masked_effective_segment_id =
	    masked_effective_segment_id;
	  segment_tlb_entry->key[om_supervisor_state] =
	    EXTRACTED64(segment_table_entry_dword_0, 58, 58);
	  segment_tlb_entry->key[om_problem_state] =
	    EXTRACTED64(segment_table_entry_dword_0, 59, 59);
	  segment_tlb_entry->invalid_access =
	    (MASKED64(segment_table_entry_dword_0, 60, 60)
	     ? om_instruction_read
	     : om_access_any);
	  segment_tlb_entry->masked_virtual_segment_id =
	    INSERTED64(EXTRACTED64(segment_table_entry_dword_1, 0, 51),
		       18-13, 63-7); /* aligned ready for pte group addr */
	  return segment_tlb_entry;
	}
      }
      segment_id_hash = ~segment_id_hash;
    }
  }
  return NULL;
#endif
}



STATIC_INLINE_VM\
(om_page_tlb_entry *)
om_virtual_to_real(om_map *map, 
		   unsigned_word ea,
		   om_segment_tlb_entry *segment_tlb_entry,
		   om_access_types access,
		   cpu *processor,
		   unsigned_word cia)
{
  om_page_tlb_entry *page_tlb_entry = (map->page_tlb->entry
				       + om_page_tlb_index(ea));

  /* is it a tlb hit? */
  if ((page_tlb_entry->masked_virtual_segment_id
       == segment_tlb_entry->masked_virtual_segment_id)
      && (page_tlb_entry->masked_page
	  == om_ea_masked_page(ea))) {
    TRACE(trace_vm, ("ea=0x%lx - tlb hit - tlb=0x%lx\n",
	       (long)ea, (long)page_tlb_entry));
    return page_tlb_entry;
  }
      
  /* drats, it is a tlb miss */
  {
    unsigned_word page_hash =
      om_hash_page(segment_tlb_entry->masked_virtual_segment_id, ea);
    int current_hash;
    for (current_hash = 0; current_hash < 2; current_hash += 1) {
      unsigned_word real_address_of_pte_group =
	(map->real_address_of_page_table
	 | (page_hash & map->page_table_hash_mask));
      unsigned_word real_address_of_pte_0;
      TRACE(trace_vm,
	    ("ea=0x%lx - htab search %d - htab=0x%lx hash=0x%lx mask=0x%lx pteg=0x%lx\n",
	     (long)ea, current_hash,
	     map->real_address_of_page_table,
	     page_hash,
	     map->page_table_hash_mask,
	     (long)real_address_of_pte_group));
      for (real_address_of_pte_0 = real_address_of_pte_group;
	   real_address_of_pte_0 < (real_address_of_pte_group
				    + sizeof_pte_group);
	   real_address_of_pte_0 += sizeof_pte) {
	unsigned_word pte_0 = om_read_word(map,
					   real_address_of_pte_0,
					   processor, cia);
	/* did we hit? */
	if (om_pte_0_valid(pte_0)
	    && (current_hash == om_pte_0_hash(pte_0))
	    && (segment_tlb_entry->masked_virtual_segment_id
		== om_pte_0_masked_vsid(pte_0))
	    && (om_ea_api(ea) == om_pte_0_api(pte_0))) {
	  unsigned_word real_address_of_pte_1 = (real_address_of_pte_0
						 + sizeof_pte / 2);
	  unsigned_word pte_1 = om_read_word(map,
					     real_address_of_pte_1,
					     processor, cia);
	  page_tlb_entry->protection = om_pte_1_pp(pte_1);
	  page_tlb_entry->changed = om_pte_1_changed(pte_1);
	  page_tlb_entry->masked_virtual_segment_id = segment_tlb_entry->masked_virtual_segment_id;
	  page_tlb_entry->masked_page = om_ea_masked_page(ea);
	  page_tlb_entry->masked_real_page_number = om_pte_1_masked_rpn(pte_1);
	  page_tlb_entry->real_address_of_pte_1 = real_address_of_pte_1;
	  if (!om_pte_1_referenced(pte_1)) {
	    om_write_word(map,
			  real_address_of_pte_1,
			  pte_1 | BIT(55),
			  processor, cia);
	    TRACE(trace_vm,
		  ("ea=0x%lx - htab hit - set ref - tlb=0x%lx &pte1=0x%lx\n",
		   (long)ea, (long)page_tlb_entry, (long)real_address_of_pte_1));
	  }
	  else {
	    TRACE(trace_vm,
		  ("ea=0x%lx - htab hit - tlb=0x%lx &pte1=0x%lx\n",
		   (long)ea, (long)page_tlb_entry, (long)real_address_of_pte_1));
	  }
	  return page_tlb_entry;
	}
      }
      page_hash = ~page_hash; /*???*/
    }
  }
  return NULL;
}


STATIC_INLINE_VM\
(void)
om_interrupt(cpu *processor,
	     unsigned_word cia,
	     unsigned_word ea,
	     om_access_types access,
	     storage_interrupt_reasons reason)
{
  switch (access) {
  case om_data_read:
    data_storage_interrupt(processor, cia, ea, reason, 0/*!is_store*/);
    break;
  case om_data_write:
    data_storage_interrupt(processor, cia, ea, reason, 1/*is_store*/);
    break;
  case om_instruction_read:
    instruction_storage_interrupt(processor, cia, reason);
    break;
  default:
    error("internal error - om_interrupt - unexpected access type %d", access);
  }
}


STATIC_INLINE_VM\
(unsigned_word)
om_translate_effective_to_real(om_map *map,
			       unsigned_word ea,
			       om_access_types access,
			       cpu *processor,
			       unsigned_word cia,
			       int abort)
{
  om_bat *bat = NULL;
  om_segment_tlb_entry *segment_tlb_entry = NULL;
  om_page_tlb_entry *page_tlb_entry = NULL;
  unsigned_word ra;

  if (!map->is_relocate) {
    ra = ea;
    TRACE(trace_vm, ("ea=0x%lx - direct map - ra=0x%lx\n",
		     (long)ea, (long)ra));
    return ra;
  }

  /* match with BAT? */
  bat = om_effective_to_bat(map, ea);
  if (bat != NULL) {
    if (!om_valid_access[1][bat->protection_bits][access]) {
      TRACE(trace_vm, ("ea=0x%lx - bat access violation\n", (long)ea));
      if (abort)
	om_interrupt(processor, cia, ea, access,
		     protection_violation_storage_interrupt);
      else
	return MASK(0, 63);
    }

    ra = ((ea & bat->block_length_mask) | bat->block_real_page_number);
    TRACE(trace_vm, ("ea=0x%lx - bat translation - ra=0x%lx\n",
		     (long)ea, (long)ra));
    return ra;
  }

  /* translate ea to va using segment map */
  segment_tlb_entry = om_effective_to_virtual(map, ea, processor, cia);
#if (WITH_TARGET_WORD_BITSIZE == 64)
  if (segment_tlb_entry == NULL) {
    TRACE(trace_vm, ("ea=0x%lx - segment tlb miss\n", (long)ea));
    if (abort)
      om_interrupt(processor, cia, ea, access,
		   segment_table_miss_storage_interrupt);
    else
      return MASK(0, 63);
  }
#endif
  /* check for invalid segment access type */
  if (segment_tlb_entry->invalid_access == access) {
    TRACE(trace_vm, ("ea=0x%lx - segment access invalid\n", (long)ea));
    if (abort)
      om_interrupt(processor, cia, ea, access,
		   protection_violation_storage_interrupt);
    else
      return MASK(0, 63);
  }

  /* lookup in PTE */
  page_tlb_entry = om_virtual_to_real(map, ea, segment_tlb_entry,
				      access,
				      processor, cia);
  if (page_tlb_entry == NULL) {
    TRACE(trace_vm, ("ea=0x%lx - page tlb miss\n", (long)ea));
    if (abort)
      om_interrupt(processor, cia, ea, access,
		   hash_table_miss_storage_interrupt);
    else
      return MASK(0, 63);
  }
  if (!(om_valid_access
	[segment_tlb_entry->key[map->is_problem_state]]
	[page_tlb_entry->protection]
	[access])) {
    TRACE(trace_vm, ("ea=0x%lx - page tlb access violation\n", (long)ea));
    if (abort)
      om_interrupt(processor, cia, ea, access,
		   protection_violation_storage_interrupt);
    else
      return MASK(0, 63);
  }

  /* update change bit as needed */
  if (access == om_data_write &&!page_tlb_entry->changed) {
    unsigned_word pte_1 = om_read_word(map,
				       page_tlb_entry->real_address_of_pte_1,
				       processor, cia);
    om_write_word(map,
		  page_tlb_entry->real_address_of_pte_1,
		  pte_1 | BIT(56),
		  processor, cia);