| /* |
| * 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. |
| */ |
| |
| #define LOG_TAG "Checkpoint" |
| #include "Checkpoint.h" |
| #include "FsCrypt.h" |
| #include "KeyStorage.h" |
| #include "VoldUtil.h" |
| #include "VolumeManager.h" |
| |
| #include <fstream> |
| #include <list> |
| #include <memory> |
| #include <string> |
| #include <thread> |
| #include <vector> |
| |
| #include <BootControlClient.h> |
| #include <android-base/file.h> |
| #include <android-base/logging.h> |
| #include <android-base/parseint.h> |
| #include <android-base/properties.h> |
| #include <android-base/unique_fd.h> |
| #include <cutils/android_reboot.h> |
| #include <fcntl.h> |
| #include <fs_mgr.h> |
| #include <linux/fs.h> |
| #include <mntent.h> |
| #include <sys/mount.h> |
| #include <sys/stat.h> |
| #include <sys/statvfs.h> |
| #include <unistd.h> |
| |
| using android::base::GetBoolProperty; |
| using android::base::GetUintProperty; |
| using android::base::SetProperty; |
| using android::binder::Status; |
| using android::fs_mgr::Fstab; |
| using android::fs_mgr::ReadFstabFromFile; |
| using android::hal::BootControlClient; |
| |
| namespace android { |
| namespace vold { |
| |
| namespace { |
| const std::string kMetadataCPFile = "/metadata/vold/checkpoint"; |
| |
| binder::Status error(const std::string& msg) { |
| PLOG(ERROR) << msg; |
| return binder::Status::fromServiceSpecificError(errno, String8(msg.c_str())); |
| } |
| |
| binder::Status error(int error, const std::string& msg) { |
| LOG(ERROR) << msg; |
| return binder::Status::fromServiceSpecificError(error, String8(msg.c_str())); |
| } |
| |
| bool setBowState(std::string const& block_device, std::string const& state) { |
| std::string bow_device = fs_mgr_find_bow_device(block_device); |
| if (bow_device.empty()) return false; |
| |
| if (!android::base::WriteStringToFile(state, bow_device + "/bow/state")) { |
| PLOG(ERROR) << "Failed to write to file " << bow_device + "/bow/state"; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| // Do any work that was deferred until the userdata filesystem checkpoint was |
| // committed. This work involves the deletion of resources that aren't covered |
| // by the userdata filesystem checkpoint, e.g. Keystore keys. |
| void DoCheckpointCommittedWork() { |
| // Take the crypt lock to provide synchronization with the Binder calls that |
| // operate on key directories. |
| std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getCryptLock()); |
| |
| DeferredCommitKeystoreKeys(); |
| fscrypt_deferred_fixate_ce_keys(); |
| } |
| |
| } // namespace |
| |
| Status cp_supportsCheckpoint(bool& result) { |
| result = false; |
| |
| for (const auto& entry : fstab_default) { |
| if (entry.fs_mgr_flags.checkpoint_blk || entry.fs_mgr_flags.checkpoint_fs) { |
| result = true; |
| return Status::ok(); |
| } |
| } |
| return Status::ok(); |
| } |
| |
| Status cp_supportsBlockCheckpoint(bool& result) { |
| result = false; |
| |
| for (const auto& entry : fstab_default) { |
| if (entry.fs_mgr_flags.checkpoint_blk) { |
| result = true; |
| return Status::ok(); |
| } |
| } |
| return Status::ok(); |
| } |
| |
| Status cp_supportsFileCheckpoint(bool& result) { |
| result = false; |
| |
| for (const auto& entry : fstab_default) { |
| if (entry.fs_mgr_flags.checkpoint_fs) { |
| result = true; |
| return Status::ok(); |
| } |
| } |
| return Status::ok(); |
| } |
| |
| Status cp_startCheckpoint(int retry) { |
| bool result; |
| if (!cp_supportsCheckpoint(result).isOk() || !result) |
| return error(ENOTSUP, "Checkpoints not supported"); |
| |
| if (retry < -1) return error(EINVAL, "Retry count must be more than -1"); |
| std::string content = std::to_string(retry + 1); |
| if (retry == -1) { |
| auto module = BootControlClient::WaitForService(); |
| if (module) { |
| std::string suffix = module->GetSuffix(module->GetCurrentSlot()); |
| if (!suffix.empty()) content += " " + suffix; |
| } |
| } |
| if (!android::base::WriteStringToFile(content, kMetadataCPFile)) |
| return error("Failed to write checkpoint file"); |
| return Status::ok(); |
| } |
| |
| namespace { |
| |
| volatile bool isCheckpointing = false; |
| volatile bool isBow = true; |
| |
| volatile bool needsCheckpointWasCalled = false; |
| |
| // Protects isCheckpointing, needsCheckpointWasCalled and code that makes decisions based on status |
| // of isCheckpointing |
| std::mutex isCheckpointingLock; |
| } |
| |
| Status cp_commitChanges() { |
| std::lock_guard<std::mutex> lock(isCheckpointingLock); |
| |
| if (!isCheckpointing) { |
| return Status::ok(); |
| } |
| if (android::base::GetProperty("persist.vold.dont_commit_checkpoint", "0") == "1") { |
| LOG(WARNING) |
| << "NOT COMMITTING CHECKPOINT BECAUSE persist.vold.dont_commit_checkpoint IS 1"; |
| return Status::ok(); |
| } |
| auto module = BootControlClient::WaitForService(); |
| if (module) { |
| auto cr = module->MarkBootSuccessful(); |
| if (!cr.success) |
| return error(EINVAL, "Error marking booted successfully: " + std::string(cr.errMsg)); |
| LOG(INFO) << "Marked slot as booted successfully."; |
| // Clears the warm reset flag for next reboot. |
| if (!SetProperty("ota.warm_reset", "0")) { |
| LOG(WARNING) << "Failed to reset the warm reset flag"; |
| } |
| } else { |
| LOG(ERROR) << "Failed to get BootControl HAL, not marking slot as successful."; |
| } |
| // Must take action for list of mounted checkpointed things here |
| // To do this, we walk the list of mounted file systems. |
| // But we also need to get the matching fstab entries to see |
| // the original flags |
| std::string err_str; |
| |
| Fstab mounts; |
| if (!ReadFstabFromFile("/proc/mounts", &mounts)) { |
| return error(EINVAL, "Failed to get /proc/mounts"); |
| } |
| |
| // Walk mounted file systems |
| for (const auto& mount_rec : mounts) { |
| const auto fstab_rec = |
| GetEntryForMountPoint(&fstab_default, mount_rec.mount_point, mount_rec.fs_type); |
| if (!fstab_rec) continue; |
| |
| if (fstab_rec->fs_mgr_flags.checkpoint_fs) { |
| if (fstab_rec->fs_type == "f2fs") { |
| std::string options = mount_rec.fs_options + ",checkpoint=enable"; |
| if (mount(mount_rec.blk_device.c_str(), mount_rec.mount_point.c_str(), "none", |
| MS_REMOUNT | fstab_rec->flags, options.c_str())) { |
| return error(EINVAL, "Failed to remount"); |
| } |
| } |
| } else if (fstab_rec->fs_mgr_flags.checkpoint_blk && isBow) { |
| if (!setBowState(mount_rec.blk_device, "2")) |
| return error(EINVAL, "Failed to set bow state"); |
| } |
| } |
| SetProperty("vold.checkpoint_committed", "1"); |
| LOG(INFO) << "Checkpoint has been committed."; |
| isCheckpointing = false; |
| if (!android::base::RemoveFileIfExists(kMetadataCPFile, &err_str)) |
| return error(err_str.c_str()); |
| |
| std::thread(DoCheckpointCommittedWork).detach(); |
| return Status::ok(); |
| } |
| |
| namespace { |
| void abort_metadata_file() { |
| std::string oldContent, newContent; |
| int retry = 0; |
| struct stat st; |
| int result = stat(kMetadataCPFile.c_str(), &st); |
| |
| // If the file doesn't exist, we aren't managing a checkpoint retry counter |
| if (result != 0) return; |
| if (!android::base::ReadFileToString(kMetadataCPFile, &oldContent)) { |
| PLOG(ERROR) << "Failed to read checkpoint file"; |
| return; |
| } |
| std::string retryContent = oldContent.substr(0, oldContent.find_first_of(" ")); |
| |
| if (!android::base::ParseInt(retryContent, &retry)) { |
| PLOG(ERROR) << "Could not parse retry count"; |
| return; |
| } |
| if (retry > 0) { |
| newContent = "0"; |
| if (!android::base::WriteStringToFile(newContent, kMetadataCPFile)) |
| PLOG(ERROR) << "Could not write checkpoint file"; |
| } |
| } |
| } // namespace |
| |
| void cp_abortChanges(const std::string& message, bool retry) { |
| if (!cp_needsCheckpoint()) return; |
| if (!retry) abort_metadata_file(); |
| android_reboot(ANDROID_RB_RESTART2, 0, message.c_str()); |
| } |
| |
| bool cp_needsRollback() { |
| std::string content; |
| bool ret; |
| |
| ret = android::base::ReadFileToString(kMetadataCPFile, &content); |
| if (ret) { |
| if (content == "0") return true; |
| if (content.substr(0, 3) == "-1 ") { |
| std::string oldSuffix = content.substr(3); |
| auto module = BootControlClient::WaitForService(); |
| std::string newSuffix; |
| |
| if (module) { |
| newSuffix = module->GetSuffix(module->GetCurrentSlot()); |
| if (oldSuffix == newSuffix) return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| bool cp_needsCheckpoint() { |
| std::lock_guard<std::mutex> lock(isCheckpointingLock); |
| |
| // Make sure we only return true during boot. See b/138952436 for discussion |
| if (needsCheckpointWasCalled) return isCheckpointing; |
| needsCheckpointWasCalled = true; |
| |
| bool ret; |
| std::string content; |
| auto module = BootControlClient::WaitForService(); |
| |
| if (isCheckpointing) return isCheckpointing; |
| // In case of INVALID slot or other failures, we do not perform checkpoint. |
| if (module && !module->IsSlotMarkedSuccessful(module->GetCurrentSlot()).value_or(true)) { |
| isCheckpointing = true; |
| return true; |
| } |
| ret = android::base::ReadFileToString(kMetadataCPFile, &content); |
| if (ret) { |
| ret = content != "0"; |
| isCheckpointing = ret; |
| return ret; |
| } |
| return false; |
| } |
| |
| bool cp_isCheckpointing() { |
| return isCheckpointing; |
| } |
| |
| namespace { |
| const std::string kSleepTimeProp = "ro.sys.cp_msleeptime"; |
| const uint32_t msleeptime_default = 1000; // 1 s |
| const uint32_t max_msleeptime = 3600000; // 1 h |
| |
| const std::string kMinFreeBytesProp = "ro.sys.cp_min_free_bytes"; |
| const uint64_t min_free_bytes_default = 100 * (1 << 20); // 100 MiB |
| |
| const std::string kCommitOnFullProp = "ro.sys.cp_commit_on_full"; |
| const bool commit_on_full_default = true; |
| |
| static void cp_healthDaemon(std::string mnt_pnt, std::string blk_device, bool is_fs_cp) { |
| struct statvfs data; |
| uint32_t msleeptime = GetUintProperty(kSleepTimeProp, msleeptime_default, max_msleeptime); |
| uint64_t min_free_bytes = |
| GetUintProperty(kMinFreeBytesProp, min_free_bytes_default, (uint64_t)-1); |
| bool commit_on_full = GetBoolProperty(kCommitOnFullProp, commit_on_full_default); |
| |
| struct timespec req; |
| req.tv_sec = msleeptime / 1000; |
| msleeptime %= 1000; |
| req.tv_nsec = msleeptime * 1000000; |
| while (isCheckpointing) { |
| uint64_t free_bytes = 0; |
| if (is_fs_cp) { |
| statvfs(mnt_pnt.c_str(), &data); |
| free_bytes = ((uint64_t) data.f_bavail) * data.f_frsize; |
| } else { |
| std::string bow_device = fs_mgr_find_bow_device(blk_device); |
| if (!bow_device.empty()) { |
| std::string content; |
| if (android::base::ReadFileToString(bow_device + "/bow/free", &content)) { |
| free_bytes = std::strtoull(content.c_str(), NULL, 10); |
| } |
| } |
| } |
| if (free_bytes < min_free_bytes) { |
| if (commit_on_full) { |
| LOG(INFO) << "Low space for checkpointing. Commiting changes"; |
| cp_commitChanges(); |
| break; |
| } else { |
| LOG(INFO) << "Low space for checkpointing. Rebooting"; |
| cp_abortChanges("checkpoint,low_space", false); |
| break; |
| } |
| } |
| nanosleep(&req, NULL); |
| } |
| } |
| |
| } // namespace |
| |
| Status cp_prepareCheckpoint() { |
| // Log to notify CTS - see b/137924328 for context |
| LOG(INFO) << "cp_prepareCheckpoint called"; |
| std::lock_guard<std::mutex> lock(isCheckpointingLock); |
| if (!isCheckpointing) { |
| return Status::ok(); |
| } |
| |
| Fstab mounts; |
| if (!ReadFstabFromFile("/proc/mounts", &mounts)) { |
| return error(EINVAL, "Failed to get /proc/mounts"); |
| } |
| |
| for (const auto& mount_rec : mounts) { |
| const auto fstab_rec = GetEntryForMountPoint(&fstab_default, mount_rec.mount_point); |
| if (!fstab_rec) continue; |
| |
| if (fstab_rec->fs_mgr_flags.checkpoint_blk) { |
| android::base::unique_fd fd( |
| TEMP_FAILURE_RETRY(open(mount_rec.mount_point.c_str(), O_RDONLY | O_CLOEXEC))); |
| if (fd == -1) { |
| PLOG(ERROR) << "Failed to open mount point" << mount_rec.mount_point; |
| continue; |
| } |
| |
| struct fstrim_range range = {}; |
| range.len = ULLONG_MAX; |
| nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME); |
| if (ioctl(fd, FITRIM, &range)) { |
| PLOG(ERROR) << "Failed to trim " << mount_rec.mount_point; |
| continue; |
| } |
| nsecs_t time = systemTime(SYSTEM_TIME_BOOTTIME) - start; |
| LOG(INFO) << "Trimmed " << range.len << " bytes on " << mount_rec.mount_point << " in " |
| << nanoseconds_to_milliseconds(time) << "ms for checkpoint"; |
| |
| isBow &= setBowState(mount_rec.blk_device, "1"); |
| } |
| if (fstab_rec->fs_mgr_flags.checkpoint_blk || fstab_rec->fs_mgr_flags.checkpoint_fs) { |
| std::thread(cp_healthDaemon, std::string(mount_rec.mount_point), |
| std::string(mount_rec.blk_device), |
| fstab_rec->fs_mgr_flags.checkpoint_fs == 1) |
| .detach(); |
| } |
| } |
| return Status::ok(); |
| } |
| |
| namespace { |
| const int kSectorSize = 512; |
| |
| typedef uint64_t sector_t; |
| |
| struct log_entry { |
| sector_t source; // in sectors of size kSectorSize |
| sector_t dest; // in sectors of size kSectorSize |
| uint32_t size; // in bytes |
| uint32_t checksum; |
| } __attribute__((packed)); |
| |
| struct log_sector_v1_0 { |
| uint32_t magic; |
| uint16_t header_version; |
| uint16_t header_size; |
| uint32_t block_size; |
| uint32_t count; |
| uint32_t sequence; |
| uint64_t sector0; |
| } __attribute__((packed)); |
| |
| // MAGIC is BOW in ascii |
| const int kMagic = 0x00574f42; |
| // Partially restored MAGIC is WOB in ascii |
| const int kPartialRestoreMagic = 0x00424f57; |
| |
| void crc32(const void* data, size_t n_bytes, uint32_t* crc) { |
| static uint32_t table[0x100] = { |
| 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, |
| 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, |
| 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, |
| 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, |
| 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, |
| 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C, |
| 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC, |
| 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, |
| 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, |
| 0xB6662D3D, |
| |
| 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, |
| 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, |
| 0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, |
| 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, |
| 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074, |
| 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, |
| 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, |
| 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, |
| 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, |
| 0xC0BA6CAD, |
| |
| 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, |
| 0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, |
| 0x0A00AE27, 0x7D079EB1, 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, |
| 0x806567CB, 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, |
| 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, |
| 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C, |
| 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 0xCB61B38C, |
| 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, |
| 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, |
| 0x5BDEAE1D, |
| |
| 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, |
| 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, |
| 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, |
| 0xF6B9265B, 0x6FB077E1, 0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, |
| 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, |
| 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, |
| 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 0xBDBDF21C, |
| 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, |
| 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, |
| 0x2D02EF8D}; |
| |
| for (size_t i = 0; i < n_bytes; ++i) { |
| *crc ^= ((uint8_t*)data)[i]; |
| *crc = table[(uint8_t)*crc] ^ *crc >> 8; |
| } |
| } |
| |
| // A map of relocations. |
| // The map must be initialized so that relocations[0] = 0 |
| // During restore, we replay the log records in reverse, copying from dest to |
| // source |
| // To validate, we must be able to read the 'dest' sectors as though they had |
| // been copied but without actually copying. This map represents how the sectors |
| // would have been moved. To read a sector s, find the index <= s and read |
| // relocations[index] + s - index |
| typedef std::map<sector_t, sector_t> Relocations; |
| |
| void relocate(Relocations& relocations, sector_t dest, sector_t source, int count) { |
| // Find first one we're equal to or greater than |
| auto s = --relocations.upper_bound(source); |
| |
| // Take slice |
| Relocations slice; |
| slice[dest] = source - s->first + s->second; |
| ++s; |
| |
| // Add rest of elements |
| for (; s != relocations.end() && s->first < source + count; ++s) |
| slice[dest - source + s->first] = s->second; |
| |
| // Split range at end of dest |
| auto dest_end = --relocations.upper_bound(dest + count); |
| relocations[dest + count] = dest + count - dest_end->first + dest_end->second; |
| |
| // Remove all elements in [dest, dest + count) |
| relocations.erase(relocations.lower_bound(dest), relocations.lower_bound(dest + count)); |
| |
| // Add new elements |
| relocations.insert(slice.begin(), slice.end()); |
| } |
| |
| // A map of sectors that have been written to. |
| // The final entry must always be False. |
| // When we restart the restore after an interruption, we must take care that |
| // when we copy from dest to source, that the block we copy to was not |
| // previously copied from. |
| // i e. A->B C->A; If we replay this sequence, we end up copying C->B |
| // We must save our partial result whenever we finish a page, or when we copy |
| // to a location that was copied from earlier (our source is an earlier dest) |
| typedef std::map<sector_t, bool> Used_Sectors; |
| |
| bool checkCollision(Used_Sectors& used_sectors, sector_t start, sector_t end) { |
| auto second_overlap = used_sectors.upper_bound(start); |
| auto first_overlap = --second_overlap; |
| |
| if (first_overlap->second) { |
| return true; |
| } else if (second_overlap != used_sectors.end() && second_overlap->first < end) { |
| return true; |
| } |
| return false; |
| } |
| |
| void markUsed(Used_Sectors& used_sectors, sector_t start, sector_t end) { |
| auto start_pos = used_sectors.insert_or_assign(start, true).first; |
| auto end_pos = used_sectors.insert_or_assign(end, false).first; |
| |
| if (start_pos == used_sectors.begin() || !std::prev(start_pos)->second) { |
| start_pos++; |
| } |
| if (std::next(end_pos) != used_sectors.end() && !std::next(end_pos)->second) { |
| end_pos++; |
| } |
| if (start_pos->first < end_pos->first) { |
| used_sectors.erase(start_pos, end_pos); |
| } |
| } |
| |
| // Restores the given log_entry's data from dest -> source |
| // If that entry is a log sector, set the magic to kPartialRestoreMagic and flush. |
| void restoreSector(int device_fd, Used_Sectors& used_sectors, std::vector<char>& ls_buffer, |
| log_entry* le, std::vector<char>& buffer) { |
| log_sector_v1_0& ls = *reinterpret_cast<log_sector_v1_0*>(&ls_buffer[0]); |
| uint32_t index = le - ((log_entry*)&ls_buffer[ls.header_size]); |
| int count = (le->size - 1) / kSectorSize + 1; |
| |
| if (checkCollision(used_sectors, le->source, le->source + count)) { |
| fsync(device_fd); |
| lseek64(device_fd, 0, SEEK_SET); |
| ls.count = index + 1; |
| ls.magic = kPartialRestoreMagic; |
| write(device_fd, &ls_buffer[0], ls.block_size); |
| fsync(device_fd); |
| used_sectors.clear(); |
| used_sectors[0] = false; |
| } |
| |
| markUsed(used_sectors, le->dest, le->dest + count); |
| |
| if (index == 0 && ls.sequence != 0) { |
| log_sector_v1_0* next = reinterpret_cast<log_sector_v1_0*>(&buffer[0]); |
| if (next->magic == kMagic) { |
| next->magic = kPartialRestoreMagic; |
| } |
| } |
| |
| lseek64(device_fd, le->source * kSectorSize, SEEK_SET); |
| write(device_fd, &buffer[0], le->size); |
| |
| if (index == 0) { |
| fsync(device_fd); |
| } |
| } |
| |
| // Read from the device |
| // If we are validating, the read occurs as though the relocations had happened |
| // returns the amount asked for or an empty buffer on error. Partial reads are considered a failure |
| std::vector<char> relocatedRead(int device_fd, Relocations const& relocations, bool validating, |
| sector_t sector, uint32_t size, uint32_t block_size) { |
| if (!validating) { |
| std::vector<char> buffer(size); |
| off64_t offset = sector * kSectorSize; |
| if (lseek64(device_fd, offset, SEEK_SET) != offset) { |
| return std::vector<char>(); |
| } |
| if (read(device_fd, &buffer[0], size) != static_cast<ssize_t>(size)) { |
| return std::vector<char>(); |
| } |
| return buffer; |
| } |
| |
| std::vector<char> buffer(size); |
| for (uint32_t i = 0; i < size; i += block_size, sector += block_size / kSectorSize) { |
| auto relocation = --relocations.upper_bound(sector); |
| off64_t offset = (sector + relocation->second - relocation->first) * kSectorSize; |
| if (lseek64(device_fd, offset, SEEK_SET) != offset) { |
| return std::vector<char>(); |
| } |
| if (read(device_fd, &buffer[i], block_size) != static_cast<ssize_t>(block_size)) { |
| return std::vector<char>(); |
| } |
| } |
| |
| return buffer; |
| } |
| |
| } // namespace |
| |
| Status cp_restoreCheckpoint(const std::string& blockDevice, int restore_limit) { |
| bool validating = true; |
| std::string action = "Validating"; |
| int restore_count = 0; |
| |
| for (;;) { |
| Relocations relocations; |
| relocations[0] = 0; |
| Status status = Status::ok(); |
| |
| LOG(INFO) << action << " checkpoint on " << blockDevice; |
| base::unique_fd device_fd(open(blockDevice.c_str(), O_RDWR | O_CLOEXEC)); |
| if (device_fd < 0) return error("Cannot open " + blockDevice); |
| |
| log_sector_v1_0 original_ls; |
| if (read(device_fd, reinterpret_cast<char*>(&original_ls), sizeof(original_ls)) != |
| sizeof(original_ls)) { |
| return error(EINVAL, "Cannot read sector"); |
| } |
| if (original_ls.magic == kPartialRestoreMagic) { |
| validating = false; |
| action = "Restoring"; |
| } else if (original_ls.magic != kMagic) { |
| return error(EINVAL, "No magic"); |
| } |
| |
| if (original_ls.block_size < sizeof(log_sector_v1_0)) { |
| return error(EINVAL, "Block size is invalid"); |
| } |
| |
| LOG(INFO) << action << " " << original_ls.sequence << " log sectors"; |
| |
| for (int sequence = original_ls.sequence; sequence >= 0 && status.isOk(); sequence--) { |
| auto ls_buffer = relocatedRead(device_fd, relocations, validating, 0, |
| original_ls.block_size, original_ls.block_size); |
| if (ls_buffer.size() != original_ls.block_size) { |
| status = error(EINVAL, "Failed to read log sector"); |
| break; |
| } |
| log_sector_v1_0& ls = *reinterpret_cast<log_sector_v1_0*>(&ls_buffer[0]); |
| |
| Used_Sectors used_sectors; |
| used_sectors[0] = false; |
| |
| if (ls.magic != kMagic && (ls.magic != kPartialRestoreMagic || validating)) { |
| status = error(EINVAL, "No magic"); |
| break; |
| } |
| |
| if (ls.block_size != original_ls.block_size) { |
| status = error(EINVAL, "Block size mismatch"); |
| break; |
| } |
| |
| if ((int)ls.sequence != sequence) { |
| status = error(EINVAL, "Expecting log sector " + std::to_string(sequence) + |
| " but got " + std::to_string(ls.sequence)); |
| break; |
| } |
| |
| if (ls.header_size < sizeof(log_sector_v1_0) || ls.header_size > ls.block_size) { |
| status = error(EINVAL, "Log sector header size is invalid"); |
| break; |
| } |
| if (ls.count < 1 || ls.count > (ls.block_size - ls.header_size) / sizeof(log_entry)) { |
| status = error(EINVAL, "Log sector count is invalid"); |
| break; |
| } |
| LOG(INFO) << action << " from log sector " << ls.sequence; |
| for (log_entry* le = |
| reinterpret_cast<log_entry*>(&ls_buffer[ls.header_size]) + ls.count - 1; |
| le >= reinterpret_cast<log_entry*>(&ls_buffer[ls.header_size]); --le) { |
| // This is very noisy - limit to DEBUG only |
| LOG(VERBOSE) << action << " " << le->size << " bytes from sector " << le->dest |
| << " to " << le->source << " with checksum " << std::hex |
| << le->checksum; |
| |
| if (ls.block_size > UINT_MAX - le->size || le->size < ls.block_size) { |
| status = error(EINVAL, "log entry is invalid"); |
| break; |
| } |
| auto buffer = relocatedRead(device_fd, relocations, validating, le->dest, le->size, |
| ls.block_size); |
| if (buffer.size() != le->size) { |
| status = error(EINVAL, "Failed to read sector"); |
| break; |
| } |
| uint32_t checksum = le->source / (ls.block_size / kSectorSize); |
| for (size_t i = 0; i < le->size; i += ls.block_size) { |
| crc32(&buffer[i], ls.block_size, &checksum); |
| } |
| |
| if (le->checksum && checksum != le->checksum) { |
| status = error(EINVAL, "Checksums don't match"); |
| break; |
| } |
| |
| if (validating) { |
| relocate(relocations, le->source, le->dest, (le->size - 1) / kSectorSize + 1); |
| } else { |
| restoreSector(device_fd, used_sectors, ls_buffer, le, buffer); |
| restore_count++; |
| if (restore_limit && restore_count >= restore_limit) { |
| status = error(EAGAIN, "Hit the test limit"); |
| break; |
| } |
| } |
| } |
| } |
| |
| if (!status.isOk()) { |
| if (!validating) { |
| LOG(ERROR) << "Checkpoint restore failed even though checkpoint validation passed"; |
| return status; |
| } |
| |
| LOG(WARNING) << "Checkpoint validation failed - attempting to roll forward"; |
| auto buffer = relocatedRead(device_fd, relocations, false, original_ls.sector0, |
| original_ls.block_size, original_ls.block_size); |
| if (buffer.size() != original_ls.block_size) { |
| return error(EINVAL, "Failed to read original sector"); |
| } |
| |
| if (lseek64(device_fd, 0, SEEK_SET) != 0) { |
| return error(EINVAL, "Failed to seek to sector 0"); |
| } |
| if (write(device_fd, &buffer[0], original_ls.block_size) != |
| static_cast<ssize_t>(original_ls.block_size)) { |
| return error(EINVAL, "Failed to write original sector"); |
| } |
| return Status::ok(); |
| } |
| |
| if (!validating) break; |
| |
| validating = false; |
| action = "Restoring"; |
| } |
| |
| return Status::ok(); |
| } |
| |
| Status cp_markBootAttempt() { |
| std::string oldContent, newContent; |
| int retry = 0; |
| struct stat st; |
| int result = stat(kMetadataCPFile.c_str(), &st); |
| |
| // If the file doesn't exist, we aren't managing a checkpoint retry counter |
| if (result != 0) return Status::ok(); |
| if (!android::base::ReadFileToString(kMetadataCPFile, &oldContent)) |
| return error("Failed to read checkpoint file"); |
| std::string retryContent = oldContent.substr(0, oldContent.find_first_of(" ")); |
| |
| if (!android::base::ParseInt(retryContent, &retry)) |
| return error(EINVAL, "Could not parse retry count"); |
| if (retry > 0) { |
| retry--; |
| |
| newContent = std::to_string(retry); |
| if (!android::base::WriteStringToFile(newContent, kMetadataCPFile)) |
| return error("Could not write checkpoint file"); |
| } |
| return Status::ok(); |
| } |
| |
| void cp_resetCheckpoint() { |
| std::lock_guard<std::mutex> lock(isCheckpointingLock); |
| needsCheckpointWasCalled = false; |
| } |
| |
| } // namespace vold |
| } // namespace android |