qubes-installer-qubes-os/storage/devicelibs/edd.py
2011-01-18 04:24:57 -05:00

98 lines
3.3 KiB
Python

#
# edd.py
# BIOS EDD data parsing functions
#
# Copyright (C) 2010 Red Hat, Inc. 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 as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Author(s): Hans de Goede <hdegoede@redhat.com>
#
import os
import struct
import logging
log = logging.getLogger("storage")
def get_edd_dict(devices):
"""Given an array of devices return a dict with the BIOS ID for them."""
edd_dict = {}
for biosdev in range(80, 80 + 15):
sysfspath = "/sys/firmware/edd/int13_dev%d" % biosdev
if not os.path.exists(sysfspath):
break # We are done
sysfspath = "/sys/firmware/edd/int13_dev%d/mbr_signature" % biosdev
if not os.path.exists(sysfspath):
log.warning("No mbrsig for biosdev: %d" % biosdev)
continue
try:
file = open(sysfspath, "r")
eddsig = file.read()
file.close()
except (IOError, OSError) as e:
log.warning("Error reading EDD mbrsig for %d: %s" %
(biosdev, str(e)))
continue
sysfspath = "/sys/firmware/edd/int13_dev%d/sectors" % biosdev
try:
file = open(sysfspath, "r")
eddsize = file.read()
file.close()
except (IOError, OSError) as e:
eddsize = None
found = []
for dev in devices:
try:
fd = os.open(dev.path, os.O_RDONLY)
os.lseek(fd, 440, 0)
mbrsig = struct.unpack('I', os.read(fd, 4))
os.close(fd)
except OSError as e:
log.warning("Error reading mbrsig from disk %s: %s" %
(dev.name, str(e)))
continue
mbrsigStr = "0x%08x\n" % mbrsig
if mbrsigStr == eddsig:
if eddsize:
sysfspath = "/sys%s/size" % dev.sysfsPath
try:
file = open(sysfspath, "r")
size = file.read()
file.close()
except (IOError, OSError) as e:
log.warning("Error getting size for: %s" % dev.name)
continue
if eddsize != size:
continue
found.append(dev.name)
if not found:
log.error("No matching mbr signature found for biosdev %d" %
biosdev)
elif len(found) > 1:
log.error("Multiple signature matches found for biosdev %d: %s" %
(biosdev, str(found)))
else:
log.info("Found %s for biosdev %d" %(found[0], biosdev))
edd_dict[found[0]] = biosdev
return edd_dict