blob: 261a2026c1a00b65e80006a394445229747e5305 [file] [log] [blame]
/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "utility.h"
#include <dirent.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <android-base/logging.h>
#include <fs_mgr_dm_linear.h>
#include <liblp/liblp.h>
#include "fastboot_device.h"
using namespace android::fs_mgr;
using namespace std::chrono_literals;
using android::base::unique_fd;
using android::hardware::boot::V1_0::Slot;
static bool OpenPhysicalPartition(const std::string& name, PartitionHandle* handle) {
std::optional<std::string> path = FindPhysicalPartition(name);
if (!path) {
return false;
}
*handle = PartitionHandle(*path);
return true;
}
static bool OpenLogicalPartition(const std::string& name, const std::string& slot,
PartitionHandle* handle) {
std::optional<std::string> path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME);
if (!path) {
return false;
}
uint32_t slot_number = SlotNumberForSlotSuffix(slot);
std::string dm_path;
if (!CreateLogicalPartition(path->c_str(), slot_number, name, true, 5s, &dm_path)) {
LOG(ERROR) << "Could not map partition: " << name;
return false;
}
auto closer = [name]() -> void { DestroyLogicalPartition(name, 5s); };
*handle = PartitionHandle(dm_path, std::move(closer));
return true;
}
bool OpenPartition(FastbootDevice* device, const std::string& name, PartitionHandle* handle) {
// We prioritize logical partitions over physical ones, and do this
// consistently for other partition operations (like getvar:partition-size).
if (LogicalPartitionExists(name, device->GetCurrentSlot())) {
if (!OpenLogicalPartition(name, device->GetCurrentSlot(), handle)) {
return false;
}
} else if (!OpenPhysicalPartition(name, handle)) {
LOG(ERROR) << "No such partition: " << name;
return false;
}
unique_fd fd(TEMP_FAILURE_RETRY(open(handle->path().c_str(), O_WRONLY | O_EXCL)));
if (fd < 0) {
PLOG(ERROR) << "Failed to open block device: " << handle->path();
return false;
}
handle->set_fd(std::move(fd));
return true;
}
std::optional<std::string> FindPhysicalPartition(const std::string& name) {
std::string path = "/dev/block/by-name/" + name;
if (access(path.c_str(), W_OK) < 0) {
return {};
}
return path;
}
static const LpMetadataPartition* FindLogicalPartition(const LpMetadata& metadata,
const std::string& name) {
for (const auto& partition : metadata.partitions) {
if (GetPartitionName(partition) == name) {
return &partition;
}
}
return nullptr;
}
bool LogicalPartitionExists(const std::string& name, const std::string& slot_suffix,
bool* is_zero_length) {
auto path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME);
if (!path) {
return false;
}
uint32_t slot_number = SlotNumberForSlotSuffix(slot_suffix);
std::unique_ptr<LpMetadata> metadata = ReadMetadata(path->c_str(), slot_number);
if (!metadata) {
return false;
}
const LpMetadataPartition* partition = FindLogicalPartition(*metadata.get(), name);
if (!partition) {
return false;
}
if (is_zero_length) {
*is_zero_length = (partition->num_extents == 0);
}
return true;
}
bool GetSlotNumber(const std::string& slot, Slot* number) {
if (slot.size() != 1) {
return false;
}
if (slot[0] < 'a' || slot[0] > 'z') {
return false;
}
*number = slot[0] - 'a';
return true;
}
std::vector<std::string> ListPartitions(FastbootDevice* device) {
std::vector<std::string> partitions;
// First get physical partitions.
struct dirent* de;
std::unique_ptr<DIR, decltype(&closedir)> by_name(opendir("/dev/block/by-name"), closedir);
while ((de = readdir(by_name.get())) != nullptr) {
if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, "..")) {
continue;
}
struct stat s;
std::string path = "/dev/block/by-name/" + std::string(de->d_name);
if (!stat(path.c_str(), &s) && S_ISBLK(s.st_mode)) {
partitions.emplace_back(de->d_name);
}
}
// Next get logical partitions.
if (auto path = FindPhysicalPartition(LP_METADATA_PARTITION_NAME)) {
uint32_t slot_number = SlotNumberForSlotSuffix(device->GetCurrentSlot());
if (auto metadata = ReadMetadata(path->c_str(), slot_number)) {
for (const auto& partition : metadata->partitions) {
std::string partition_name = GetPartitionName(partition);
partitions.emplace_back(partition_name);
}
}
}
return partitions;
}