1 # Copyright 2015 The Chromium OS Authors. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 import logging 6 import os 7 import re 8 9 import common 10 from autotest_lib.client.common_lib import error 11 from autotest_lib.server import test 12 13 14 # The /dev directory mapping partition names to block devices. 15 _BLK_DEV_BY_NAME_DIR = '/dev/block/by-name' 16 # By default, we kill and recover the active system partition. 17 _DEFAULT_PART_NAME = 'system_X' 18 19 20 class brillo_RecoverFromBadImage(test.test): 21 """Ensures that a Brillo device can recover from a bad image.""" 22 version = 1 23 24 25 def resolve_slot(self, host, partition): 26 """Resolves a partition slot (if any). 27 28 @param host: A host object representing the DUT. 29 @param partition: The name of the partition we are using. If it ends 30 with '_X' then we attempt to substitute it with some 31 non-active slot. 32 33 @return A pair consisting of a fully resolved partition name and slot 34 index; the latter is None if the partition is not slotted. 35 36 @raise TestError: If a target slot could not be resolved. 37 """ 38 # Check if the partition is slotted. 39 if not re.match('.+_[a-zX]$', partition): 40 return partition, None 41 42 try: 43 current_slot = int( 44 host.run_output('bootctl get-current-slot').strip()) 45 if partition[-1] == 'X': 46 # Find a non-active target slot we could use. 47 num_slots = int( 48 host.run_output('bootctl get-number-slots').strip()) 49 if num_slots < 2: 50 raise error.TestError( 51 'Device has no non-active slot that we can use') 52 target_slot = 0 if current_slot else 1 53 partition = partition[:-1] + chr(ord('a') + target_slot) 54 logging.info( 55 'Current slot is %d, partition resolved to %s ' 56 '(slot %d)', current_slot, partition, target_slot) 57 else: 58 # Make sure the partition slot is different from the active one. 59 target_slot = ord(partition[-1]) - ord('a') 60 if target_slot == current_slot: 61 target_slot = None 62 logging.warning( 63 'Partition %s is associated with the current boot ' 64 'slot (%d), wiping it might fail if it is mounted', 65 partition, current_slot) 66 except error.AutoservError: 67 raise error.TestError('Error resolving device slots') 68 69 return partition, target_slot 70 71 72 def find_partition_device(self, host, partition): 73 """Returns the block device of the partition. 74 75 @param host: A host object representing the DUT. 76 @param partition: The name of the partition we are using. 77 78 @return Path to the device containing the partition. 79 80 @raise TestError: If the partition name could not be mapped to a device. 81 """ 82 try: 83 cmd = 'find %s -type l' % os.path.join(_BLK_DEV_BY_NAME_DIR, '') 84 for device in host.run_output(cmd).splitlines(): 85 if os.path.basename(device) == partition: 86 logging.info('Mapped partition %s to device %s', 87 partition, device) 88 return device 89 except error.AutoservError: 90 raise error.TestError( 91 'Error finding device for partition %s' % partition) 92 raise error.TestError( 93 'No device found for partition %s' % partition) 94 95 96 def get_device_block_info(self, host, device): 97 """Returns the block size and count for a device. 98 99 @param host: A host object representing the DUT. 100 @param device: Path to a block device. 101 102 @return A pair consisting of the block size (in bytes) and the total 103 number of blocks on the device. 104 105 @raise TestError: If we failed to get the block info for the device. 106 """ 107 try: 108 block_size = int( 109 host.run_output('blockdev --getbsz %s' % device).strip()) 110 device_size = int( 111 host.run_output('blockdev --getsize64 %s' % device).strip()) 112 except error.AutoservError: 113 raise error.TestError( 114 'Failed to get block info for device %s' % device) 115 return block_size, device_size / block_size 116 117 118 def run_once(self, host=None, image_file=None, partition=_DEFAULT_PART_NAME, 119 device=None): 120 """Runs the test. 121 122 @param host: A host object representing the DUT. 123 @param image_file: Image file to flash to the partition. 124 @param partition: Name of the partition to wipe/recover. 125 @param device: Path to the partition block device. 126 127 @raise TestError: Something went wrong while trying to execute the test. 128 @raise TestFail: The test failed. 129 """ 130 # Check that the image file exists. 131 if image_file is None: 132 raise error.TestError('No image file provided') 133 if not os.path.isfile(image_file): 134 raise error.TestError('Image file %s not found' % image_file) 135 136 try: 137 # Resolve partition name and slot. 138 partition, target_slot = self.resolve_slot(host, partition) 139 140 # Figure out the partition device. 141 if device is None: 142 device = self.find_partition_device(host, partition) 143 144 # Find the block size and count for the device. 145 block_size, num_blocks = self.get_device_block_info(host, device) 146 147 # Wipe the partition. 148 logging.info('Wiping partition %s (%s)', partition, device) 149 cmd = ('dd if=/dev/zero of=%s bs=%d count=%d' % 150 (device, block_size, num_blocks)) 151 run_err = 'Failed to wipe partition using %s' % cmd 152 host.run(cmd) 153 154 # Switch to the target slot, if required. 155 if target_slot is not None: 156 run_err = 'Error setting the active boot slot' 157 host.run('bootctl set-active-boot-slot %d' % target_slot) 158 159 # Re-flash the partition with fastboot. 160 run_err = 'Failed to reboot the device into fastboot' 161 host.ensure_bootloader_mode() 162 run_err = 'Failed to flash image to partition %s' % partition 163 host.fastboot_run('flash', args=(partition, image_file)) 164 165 # Reboot the device. 166 run_err = 'Failed to reboot the device after flashing image' 167 host.ensure_adb_mode() 168 169 # Make sure we've booted from the alternate slot, if required. 170 if target_slot is not None: 171 run_err = 'Error checking the current boot slot' 172 current_slot = int( 173 host.run_output('bootctl get-current-slot').strip()) 174 if current_slot != target_slot: 175 logging.error('Rebooted from slot %d instead of %d', 176 current_slot, target_slot) 177 raise error.TestError( 178 'Device did not reboot from the expected slot') 179 except error.AutoservError: 180 raise error.TestFail(run_err) 181
