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mm.py 8.94 KiB
# Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 and
# only version 2 as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
import bitops
def page_buddy(ramdump, page):
mapcount_offset = ramdump.field_offset('struct page', '_mapcount')
val = ramdump.read_int(page + mapcount_offset)
# -128 is the magic for in the buddy allocator
return val == 0xffffff80
def get_debug_flags(ramdump, page):
debug_flag_offset = ramdump.field_offset('struct page', 'debug_flags')
flagval = ramdump.read_word(page + debug_flag_offset)
return flagval
def page_zonenum(page_flags):
# save this in a variable somewhere...
return (page_flags >> 26) & 3
def page_to_nid(page_flags):
return 0
def page_zone(ramdump, page):
contig_page_data = ramdump.address_of('contig_page_data')
node_zones_offset = ramdump.field_offset(
'struct pglist_data', 'node_zones')
page_flags_offset = ramdump.field_offset('struct page', 'flags')
zone_size = ramdump.sizeof('struct zone')
page_flags = ramdump.read_word(page + page_flags_offset)
if page_flags is None:
return None
zone = contig_page_data + node_zones_offset + \
(page_zonenum(page_flags) * zone_size)
return zone
def zone_is_highmem(ramdump, zone):
if not ramdump.is_config_defined('CONFIG_HIGHMEM'):
return False
if zone is None:
return False
# not at all how linux does it but it works for our purposes...
zone_name_offset = ramdump.field_offset('struct zone', 'name')
zone_name_addr = ramdump.read_word(zone + zone_name_offset)
if zone_name_addr is None:
return False
zone_name = ramdump.read_cstring(zone_name_addr, 48)
if zone_name is None:
# XXX do something?
return False
if zone_name == 'HighMem':
return True
else:
return False
def hash32(val, bits):
chash = c_uint(val * 0x9e370001).value
return chash >> (32 - bits)
def page_slot(ramdump, page):
hashed = hash32(page, 7)
htable = ramdump.address_of('page_address_htable')
htable_size = ramdump.sizeof('page_address_htable[0]')
return htable + htable_size * hashed
def page_to_section(page_flags):
# again savefn8n variable
return (page_flags >> 28) & 0xF
def nr_to_section(ramdump, sec_num):
memsection_struct_size = ramdump.sizeof('struct mem_section')
sections_per_root = 4096 / memsection_struct_size
sect_nr_to_root = sec_num / sections_per_root
masked = sec_num & (sections_per_root - 1)
mem_section_addr = ramdump.address_of('mem_section')
mem_section = ramdump.read_word(mem_section_addr)
if mem_section is None:
return None
return mem_section + memsection_struct_size * (sect_nr_to_root * sections_per_root + masked)
def section_mem_map_addr(ramdump, section):
map_offset = ramdump.field_offset('struct mem_section', 'section_mem_map')
result = ramdump.read_word(section + map_offset)
return result & ~((1 << 2) - 1)
def pfn_to_section_nr(pfn):
return pfn >> (28 - 12)
def pfn_to_section(ramdump, pfn):
return nr_to_section(ramdump, pfn_to_section_nr(pfn))
def pfn_to_page_sparse(ramdump, pfn):
sec = pfn_to_section(ramdump, pfn)
sizeof_page = ramdump.sizeof('struct page')
return section_mem_map_addr(ramdump, sec) + pfn * sizeof_page
def page_to_pfn_sparse(ramdump, page):
page_flags_offset = ramdump.field_offset('struct page', 'flags')
sizeof_page = ramdump.sizeof('struct page')
flags = ramdump.read_word(page + page_flags_offset)
if flags is None:
return 0
section = page_to_section(flags)
nr = nr_to_section(ramdump, section)
addr = section_mem_map_addr(ramdump, nr)
# divide by struct page size for division fun
return (page - addr) / sizeof_page
def get_vmemmap(ramdump):
# See: include/asm-generic/pgtable-nopud.h,
# arch/arm64/include/asm/pgtable-hwdef.h,
# arch/arm64/include/asm/pgtable.h
nlevels = int(ramdump.get_config_val("CONFIG_ARM64_PGTABLE_LEVELS"))
if ramdump.is_config_defined("CONFIG_ARM64_64K_PAGES"):
page_shift = 16
else:
page_shift = 12
pgdir_shift = ((page_shift - 3) * nlevels) + 3
pud_shift = pgdir_shift
pud_size = 1 << pud_shift
va_bits = int(ramdump.get_config_val("CONFIG_ARM64_VA_BITS"))
spsize = ramdump.sizeof('struct page')
vmemmap_size = bitops.align((1 << (va_bits - page_shift)) * spsize,
pud_size)
vmalloc_end = ramdump.page_offset - pud_size - vmemmap_size
return vmalloc_end
def page_to_pfn_vmemmap(ramdump, page):
vmemmap = get_vmemmap(ramdump)
page_size = ramdump.sizeof('struct page')
return ((page - vmemmap) / page_size)
def pfn_to_page_vmemmap(ramdump, pfn):
vmemmap = get_vmemmap(ramdump)
page_size = ramdump.sizeof('struct page')
return vmemmap + (pfn * page_size)
def page_to_pfn_flat(ramdump, page):
mem_map_addr = ramdump.address_of('mem_map')
mem_map = ramdump.read_word(mem_map_addr)
page_size = ramdump.sizeof('struct page')
# XXX Needs to change for LPAE
pfn_offset = ramdump.phys_offset >> 12
return ((page - mem_map) / page_size) + pfn_offset
def pfn_to_page_flat(ramdump, pfn):
mem_map_addr = ramdump.address_of('mem_map')
mem_map = ramdump.read_word(mem_map_addr)
page_size = ramdump.sizeof('struct page')
# XXX Needs to change for LPAE
pfn_offset = ramdump.phys_offset >> 12
return mem_map + ((pfn - pfn_offset) * page_size)
def page_to_pfn(ramdump, page):
if ramdump.arm64:
return page_to_pfn_vmemmap(ramdump, page)
if ramdump.is_config_defined('CONFIG_SPARSEMEM'):
return page_to_pfn_sparse(ramdump, page)
else:
return page_to_pfn_flat(ramdump, page)
def pfn_to_page(ramdump, pfn):
if ramdump.arm64:
return pfn_to_page_vmemmap(ramdump, pfn)
if ramdump.is_config_defined('CONFIG_SPARSEMEM'):
return pfn_to_page_sparse(ramdump, pfn)
else:
return pfn_to_page_flat(ramdump, pfn)
def sparsemem_lowmem_page_address(ramdump, page):
membank1_start = ramdump.read_word(ramdump.address_of('membank1_start'))
membank0_size = ramdump.read_word(ramdump.address_of('membank0_size'))
# XXX currently magic
membank0_phys_offset = ramdump.phys_offset
membank0_page_offset = ramdump.page_offset
membank1_phys_offset = membank1_start
membank1_page_offset = membank0_page_offset + membank0_size
phys = page_to_pfn(ramdump, page) << 12
if phys >= membank1_start:
return phys - membank1_phys_offset + membank1_page_offset
else:
return phys - membank0_phys_offset + membank0_page_offset
def dont_map_hole_lowmem_page_address(ramdump, page):
phys = page_to_pfn(ramdump, page) << 12
hole_end_addr = ramdump.address_of('memory_hole_end')
if hole_end_addr is None:
hole_end_addr = ramdump.address_of('membank1_start')
hole_offset_addr = ramdump.address_of('memory_hole_offset')
if hole_offset_addr is None:
hole_offset_addr = ramdump.address_of('membank0_size')
hole_end = ramdump.read_word(hole_end_addr)
hole_offset = ramdump.read_word(hole_offset_addr)
if hole_end != 0 and phys >= hole_end:
return phys - hole_end + hole_offset + ramdump.page_offset
else:
return phys - ramdump.phys_offset + ramdump.page_offset
def normal_lowmem_page_address(ramdump, page):
phys = page_to_pfn(ramdump, page) << 12
return phys - ramdump.phys_offset + ramdump.page_offset
def lowmem_page_address(ramdump, page):
if ramdump.is_config_defined('CONFIG_SPARSEMEM') and not ramdump.arm64:
return sparsemem_lowmem_page_address(ramdump, page)
elif ramdump.is_config_defined('CONFIG_DONT_MAP_HOLE_AFTER_MEMBANK0'):
return dont_map_hole_lowmem_page_address(ramdump, page)
else:
return normal_lowmem_page_address(ramdump, page)
def page_address(ramdump, page):
if not zone_is_highmem(ramdump, page_zone(ramdump, page)):
return lowmem_page_address(ramdump, page)
pas = page_slot(ramdump, page)
lh_offset = ramdump.field_offset('struct page_address_slot', 'lh')
start = pas + lh_offset
pam = start
while True:
pam = pam - lh_offset
pam_page_offset = ramdump.field_offset(
'struct page_address_map', 'page')
pam_virtual_offset = ramdump.field_offset(
'struct page_address_map', 'virtual')
pam_page = ramdump.read_word(pam + pam_page_offset)
if pam_page == page:
ret = ramdump.read_word(pam + pam_virtual_offset)
return ret
pam = ramdump.read_word(pam + lh_offset)
if pam == start:
return None