Checkpoint.cpp 27 KB

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  1. /*
  2. * Copyright (C) 2018 The Android Open Source Project
  3. *
  4. * Licensed under the Apache License, Version 2.0 (the "License");
  5. * you may not use this file except in compliance with the License.
  6. * You may obtain a copy of the License at
  7. *
  8. * http://www.apache.org/licenses/LICENSE-2.0
  9. *
  10. * Unless required by applicable law or agreed to in writing, software
  11. * distributed under the License is distributed on an "AS IS" BASIS,
  12. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13. * See the License for the specific language governing permissions and
  14. * limitations under the License.
  15. */
  16. #define LOG_TAG "Checkpoint"
  17. #include "Checkpoint.h"
  18. #include "VoldUtil.h"
  19. #include "VolumeManager.h"
  20. #include <fstream>
  21. #include <list>
  22. #include <memory>
  23. #include <string>
  24. #include <thread>
  25. #include <vector>
  26. #include <android-base/file.h>
  27. #include <android-base/logging.h>
  28. #include <android-base/parseint.h>
  29. #include <android-base/properties.h>
  30. #include <android-base/unique_fd.h>
  31. #include <android/hardware/boot/1.0/IBootControl.h>
  32. #include <cutils/android_reboot.h>
  33. #include <fcntl.h>
  34. #include <fs_mgr.h>
  35. #include <linux/fs.h>
  36. #include <mntent.h>
  37. #include <sys/mount.h>
  38. #include <sys/stat.h>
  39. #include <sys/statvfs.h>
  40. #include <unistd.h>
  41. using android::base::GetBoolProperty;
  42. using android::base::GetUintProperty;
  43. using android::base::SetProperty;
  44. using android::binder::Status;
  45. using android::fs_mgr::Fstab;
  46. using android::fs_mgr::ReadDefaultFstab;
  47. using android::fs_mgr::ReadFstabFromFile;
  48. using android::hardware::hidl_string;
  49. using android::hardware::boot::V1_0::BoolResult;
  50. using android::hardware::boot::V1_0::CommandResult;
  51. using android::hardware::boot::V1_0::IBootControl;
  52. using android::hardware::boot::V1_0::Slot;
  53. namespace android {
  54. namespace vold {
  55. namespace {
  56. const std::string kMetadataCPFile = "/metadata/vold/checkpoint";
  57. bool setBowState(std::string const& block_device, std::string const& state) {
  58. std::string bow_device = fs_mgr_find_bow_device(block_device);
  59. if (bow_device.empty()) return false;
  60. if (!android::base::WriteStringToFile(state, bow_device + "/bow/state")) {
  61. PLOG(ERROR) << "Failed to write to file " << bow_device + "/bow/state";
  62. return false;
  63. }
  64. return true;
  65. }
  66. } // namespace
  67. Status cp_supportsCheckpoint(bool& result) {
  68. result = false;
  69. for (const auto& entry : fstab_default) {
  70. if (entry.fs_mgr_flags.checkpoint_blk || entry.fs_mgr_flags.checkpoint_fs) {
  71. result = true;
  72. return Status::ok();
  73. }
  74. }
  75. return Status::ok();
  76. }
  77. Status cp_supportsBlockCheckpoint(bool& result) {
  78. result = false;
  79. for (const auto& entry : fstab_default) {
  80. if (entry.fs_mgr_flags.checkpoint_blk) {
  81. result = true;
  82. return Status::ok();
  83. }
  84. }
  85. return Status::ok();
  86. }
  87. Status cp_supportsFileCheckpoint(bool& result) {
  88. result = false;
  89. for (const auto& entry : fstab_default) {
  90. if (entry.fs_mgr_flags.checkpoint_fs) {
  91. result = true;
  92. return Status::ok();
  93. }
  94. }
  95. return Status::ok();
  96. }
  97. Status cp_startCheckpoint(int retry) {
  98. if (retry < -1) return Status::fromExceptionCode(EINVAL, "Retry count must be more than -1");
  99. std::string content = std::to_string(retry + 1);
  100. if (retry == -1) {
  101. sp<IBootControl> module = IBootControl::getService();
  102. if (module) {
  103. std::string suffix;
  104. auto cb = [&suffix](hidl_string s) { suffix = s; };
  105. if (module->getSuffix(module->getCurrentSlot(), cb).isOk()) content += " " + suffix;
  106. }
  107. }
  108. if (!android::base::WriteStringToFile(content, kMetadataCPFile))
  109. return Status::fromExceptionCode(errno, "Failed to write checkpoint file");
  110. return Status::ok();
  111. }
  112. namespace {
  113. volatile bool isCheckpointing = false;
  114. }
  115. Status cp_commitChanges() {
  116. if (!isCheckpointing) {
  117. return Status::ok();
  118. }
  119. if (android::base::GetProperty("persist.vold.dont_commit_checkpoint", "0") == "1") {
  120. LOG(WARNING)
  121. << "NOT COMMITTING CHECKPOINT BECAUSE persist.vold.dont_commit_checkpoint IS 1";
  122. return Status::ok();
  123. }
  124. sp<IBootControl> module = IBootControl::getService();
  125. if (module) {
  126. CommandResult cr;
  127. module->markBootSuccessful([&cr](CommandResult result) { cr = result; });
  128. if (!cr.success) {
  129. std::string msg = "Error marking booted successfully: " + std::string(cr.errMsg);
  130. return Status::fromExceptionCode(EINVAL, String8(msg.c_str()));
  131. }
  132. LOG(INFO) << "Marked slot as booted successfully.";
  133. }
  134. // Must take action for list of mounted checkpointed things here
  135. // To do this, we walk the list of mounted file systems.
  136. // But we also need to get the matching fstab entries to see
  137. // the original flags
  138. std::string err_str;
  139. Fstab mounts;
  140. if (!ReadFstabFromFile("/proc/mounts", &mounts)) {
  141. return Status::fromExceptionCode(EINVAL, "Failed to get /proc/mounts");
  142. }
  143. // Walk mounted file systems
  144. for (const auto& mount_rec : mounts) {
  145. const auto fstab_rec = GetEntryForMountPoint(&fstab_default, mount_rec.mount_point);
  146. if (!fstab_rec) continue;
  147. if (fstab_rec->fs_mgr_flags.checkpoint_fs) {
  148. if (fstab_rec->fs_type == "f2fs") {
  149. std::string options = mount_rec.fs_options + ",checkpoint=enable";
  150. if (mount(mount_rec.blk_device.c_str(), mount_rec.mount_point.c_str(), "none",
  151. MS_REMOUNT | fstab_rec->flags, options.c_str())) {
  152. return Status::fromExceptionCode(EINVAL, "Failed to remount");
  153. }
  154. }
  155. } else if (fstab_rec->fs_mgr_flags.checkpoint_blk) {
  156. if (!setBowState(mount_rec.blk_device, "2"))
  157. return Status::fromExceptionCode(EINVAL, "Failed to set bow state");
  158. }
  159. }
  160. SetProperty("vold.checkpoint_committed", "1");
  161. LOG(INFO) << "Checkpoint has been committed.";
  162. isCheckpointing = false;
  163. if (!android::base::RemoveFileIfExists(kMetadataCPFile, &err_str))
  164. return Status::fromExceptionCode(errno, err_str.c_str());
  165. return Status::ok();
  166. }
  167. namespace {
  168. void abort_metadata_file() {
  169. std::string oldContent, newContent;
  170. int retry = 0;
  171. struct stat st;
  172. int result = stat(kMetadataCPFile.c_str(), &st);
  173. // If the file doesn't exist, we aren't managing a checkpoint retry counter
  174. if (result != 0) return;
  175. if (!android::base::ReadFileToString(kMetadataCPFile, &oldContent)) {
  176. PLOG(ERROR) << "Failed to read checkpoint file";
  177. return;
  178. }
  179. std::string retryContent = oldContent.substr(0, oldContent.find_first_of(" "));
  180. if (!android::base::ParseInt(retryContent, &retry)) {
  181. PLOG(ERROR) << "Could not parse retry count";
  182. return;
  183. }
  184. if (retry > 0) {
  185. newContent = "0";
  186. if (!android::base::WriteStringToFile(newContent, kMetadataCPFile))
  187. PLOG(ERROR) << "Could not write checkpoint file";
  188. }
  189. }
  190. } // namespace
  191. void cp_abortChanges(const std::string& message, bool retry) {
  192. if (!cp_needsCheckpoint()) return;
  193. if (!retry) abort_metadata_file();
  194. android_reboot(ANDROID_RB_RESTART2, 0, message.c_str());
  195. }
  196. bool cp_needsRollback() {
  197. std::string content;
  198. bool ret;
  199. ret = android::base::ReadFileToString(kMetadataCPFile, &content);
  200. if (ret) {
  201. if (content == "0") return true;
  202. if (content.substr(0, 3) == "-1 ") {
  203. std::string oldSuffix = content.substr(3);
  204. sp<IBootControl> module = IBootControl::getService();
  205. std::string newSuffix;
  206. if (module) {
  207. auto cb = [&newSuffix](hidl_string s) { newSuffix = s; };
  208. module->getSuffix(module->getCurrentSlot(), cb);
  209. if (oldSuffix == newSuffix) return true;
  210. }
  211. }
  212. }
  213. return false;
  214. }
  215. bool cp_needsCheckpoint() {
  216. // Make sure we only return true during boot. See b/138952436 for discussion
  217. static bool called_once = false;
  218. if (called_once) return isCheckpointing;
  219. called_once = true;
  220. bool ret;
  221. std::string content;
  222. sp<IBootControl> module = IBootControl::getService();
  223. if (isCheckpointing) return isCheckpointing;
  224. if (module && module->isSlotMarkedSuccessful(module->getCurrentSlot()) == BoolResult::FALSE) {
  225. isCheckpointing = true;
  226. return true;
  227. }
  228. ret = android::base::ReadFileToString(kMetadataCPFile, &content);
  229. if (ret) {
  230. ret = content != "0";
  231. isCheckpointing = ret;
  232. return ret;
  233. }
  234. return false;
  235. }
  236. namespace {
  237. const std::string kSleepTimeProp = "ro.sys.cp_msleeptime";
  238. const uint32_t msleeptime_default = 1000; // 1 s
  239. const uint32_t max_msleeptime = 3600000; // 1 h
  240. const std::string kMinFreeBytesProp = "ro.sys.cp_min_free_bytes";
  241. const uint64_t min_free_bytes_default = 100 * (1 << 20); // 100 MiB
  242. const std::string kCommitOnFullProp = "ro.sys.cp_commit_on_full";
  243. const bool commit_on_full_default = true;
  244. static void cp_healthDaemon(std::string mnt_pnt, std::string blk_device, bool is_fs_cp) {
  245. struct statvfs data;
  246. uint32_t msleeptime = GetUintProperty(kSleepTimeProp, msleeptime_default, max_msleeptime);
  247. uint64_t min_free_bytes =
  248. GetUintProperty(kMinFreeBytesProp, min_free_bytes_default, (uint64_t)-1);
  249. bool commit_on_full = GetBoolProperty(kCommitOnFullProp, commit_on_full_default);
  250. struct timespec req;
  251. req.tv_sec = msleeptime / 1000;
  252. msleeptime %= 1000;
  253. req.tv_nsec = msleeptime * 1000000;
  254. while (isCheckpointing) {
  255. uint64_t free_bytes = 0;
  256. if (is_fs_cp) {
  257. statvfs(mnt_pnt.c_str(), &data);
  258. free_bytes = data.f_bavail * data.f_frsize;
  259. } else {
  260. std::string bow_device = fs_mgr_find_bow_device(blk_device);
  261. if (!bow_device.empty()) {
  262. std::string content;
  263. if (android::base::ReadFileToString(bow_device + "/bow/free", &content)) {
  264. free_bytes = std::strtoul(content.c_str(), NULL, 10);
  265. }
  266. }
  267. }
  268. if (free_bytes < min_free_bytes) {
  269. if (commit_on_full) {
  270. LOG(INFO) << "Low space for checkpointing. Commiting changes";
  271. cp_commitChanges();
  272. break;
  273. } else {
  274. LOG(INFO) << "Low space for checkpointing. Rebooting";
  275. cp_abortChanges("checkpoint,low_space", false);
  276. break;
  277. }
  278. }
  279. nanosleep(&req, NULL);
  280. }
  281. }
  282. } // namespace
  283. Status cp_prepareCheckpoint() {
  284. // Log to notify CTS - see b/137924328 for context
  285. LOG(INFO) << "cp_prepareCheckpoint called";
  286. if (!isCheckpointing) {
  287. return Status::ok();
  288. }
  289. Fstab mounts;
  290. if (!ReadFstabFromFile("/proc/mounts", &mounts)) {
  291. return Status::fromExceptionCode(EINVAL, "Failed to get /proc/mounts");
  292. }
  293. for (const auto& mount_rec : mounts) {
  294. const auto fstab_rec = GetEntryForMountPoint(&fstab_default, mount_rec.mount_point);
  295. if (!fstab_rec) continue;
  296. if (fstab_rec->fs_mgr_flags.checkpoint_blk) {
  297. android::base::unique_fd fd(
  298. TEMP_FAILURE_RETRY(open(mount_rec.mount_point.c_str(), O_RDONLY | O_CLOEXEC)));
  299. if (fd == -1) {
  300. PLOG(ERROR) << "Failed to open mount point" << mount_rec.mount_point;
  301. continue;
  302. }
  303. struct fstrim_range range = {};
  304. range.len = ULLONG_MAX;
  305. nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME);
  306. if (ioctl(fd, FITRIM, &range)) {
  307. PLOG(ERROR) << "Failed to trim " << mount_rec.mount_point;
  308. continue;
  309. }
  310. nsecs_t time = systemTime(SYSTEM_TIME_BOOTTIME) - start;
  311. LOG(INFO) << "Trimmed " << range.len << " bytes on " << mount_rec.mount_point << " in "
  312. << nanoseconds_to_milliseconds(time) << "ms for checkpoint";
  313. setBowState(mount_rec.blk_device, "1");
  314. }
  315. if (fstab_rec->fs_mgr_flags.checkpoint_blk || fstab_rec->fs_mgr_flags.checkpoint_fs) {
  316. std::thread(cp_healthDaemon, std::string(mount_rec.mount_point),
  317. std::string(mount_rec.blk_device),
  318. fstab_rec->fs_mgr_flags.checkpoint_fs == 1)
  319. .detach();
  320. }
  321. }
  322. return Status::ok();
  323. }
  324. namespace {
  325. const int kSectorSize = 512;
  326. typedef uint64_t sector_t;
  327. struct log_entry {
  328. sector_t source; // in sectors of size kSectorSize
  329. sector_t dest; // in sectors of size kSectorSize
  330. uint32_t size; // in bytes
  331. uint32_t checksum;
  332. } __attribute__((packed));
  333. struct log_sector_v1_0 {
  334. uint32_t magic;
  335. uint16_t header_version;
  336. uint16_t header_size;
  337. uint32_t block_size;
  338. uint32_t count;
  339. uint32_t sequence;
  340. uint64_t sector0;
  341. } __attribute__((packed));
  342. // MAGIC is BOW in ascii
  343. const int kMagic = 0x00574f42;
  344. // Partially restored MAGIC is WOB in ascii
  345. const int kPartialRestoreMagic = 0x00424f57;
  346. void crc32(const void* data, size_t n_bytes, uint32_t* crc) {
  347. static uint32_t table[0x100] = {
  348. 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535,
  349. 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD,
  350. 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D,
  351. 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
  352. 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4,
  353. 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C,
  354. 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC,
  355. 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
  356. 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB,
  357. 0xB6662D3D,
  358. 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5,
  359. 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D,
  360. 0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED,
  361. 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
  362. 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074,
  363. 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC,
  364. 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C,
  365. 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
  366. 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B,
  367. 0xC0BA6CAD,
  368. 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615,
  369. 0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D,
  370. 0x0A00AE27, 0x7D079EB1, 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D,
  371. 0x806567CB, 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
  372. 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4,
  373. 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C,
  374. 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 0xCB61B38C,
  375. 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
  376. 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B,
  377. 0x5BDEAE1D,
  378. 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785,
  379. 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D,
  380. 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD,
  381. 0xF6B9265B, 0x6FB077E1, 0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
  382. 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354,
  383. 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC,
  384. 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 0xBDBDF21C,
  385. 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
  386. 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B,
  387. 0x2D02EF8D};
  388. for (size_t i = 0; i < n_bytes; ++i) {
  389. *crc ^= ((uint8_t*)data)[i];
  390. *crc = table[(uint8_t)*crc] ^ *crc >> 8;
  391. }
  392. }
  393. // A map of relocations.
  394. // The map must be initialized so that relocations[0] = 0
  395. // During restore, we replay the log records in reverse, copying from dest to
  396. // source
  397. // To validate, we must be able to read the 'dest' sectors as though they had
  398. // been copied but without actually copying. This map represents how the sectors
  399. // would have been moved. To read a sector s, find the index <= s and read
  400. // relocations[index] + s - index
  401. typedef std::map<sector_t, sector_t> Relocations;
  402. void relocate(Relocations& relocations, sector_t dest, sector_t source, int count) {
  403. // Find first one we're equal to or greater than
  404. auto s = --relocations.upper_bound(source);
  405. // Take slice
  406. Relocations slice;
  407. slice[dest] = source - s->first + s->second;
  408. ++s;
  409. // Add rest of elements
  410. for (; s != relocations.end() && s->first < source + count; ++s)
  411. slice[dest - source + s->first] = s->second;
  412. // Split range at end of dest
  413. auto dest_end = --relocations.upper_bound(dest + count);
  414. relocations[dest + count] = dest + count - dest_end->first + dest_end->second;
  415. // Remove all elements in [dest, dest + count)
  416. relocations.erase(relocations.lower_bound(dest), relocations.lower_bound(dest + count));
  417. // Add new elements
  418. relocations.insert(slice.begin(), slice.end());
  419. }
  420. // A map of sectors that have been written to.
  421. // The final entry must always be False.
  422. // When we restart the restore after an interruption, we must take care that
  423. // when we copy from dest to source, that the block we copy to was not
  424. // previously copied from.
  425. // i e. A->B C->A; If we replay this sequence, we end up copying C->B
  426. // We must save our partial result whenever we finish a page, or when we copy
  427. // to a location that was copied from earlier (our source is an earlier dest)
  428. typedef std::map<sector_t, bool> Used_Sectors;
  429. bool checkCollision(Used_Sectors& used_sectors, sector_t start, sector_t end) {
  430. auto second_overlap = used_sectors.upper_bound(start);
  431. auto first_overlap = --second_overlap;
  432. if (first_overlap->second) {
  433. return true;
  434. } else if (second_overlap != used_sectors.end() && second_overlap->first < end) {
  435. return true;
  436. }
  437. return false;
  438. }
  439. void markUsed(Used_Sectors& used_sectors, sector_t start, sector_t end) {
  440. auto start_pos = used_sectors.insert_or_assign(start, true).first;
  441. auto end_pos = used_sectors.insert_or_assign(end, false).first;
  442. if (start_pos == used_sectors.begin() || !std::prev(start_pos)->second) {
  443. start_pos++;
  444. }
  445. if (std::next(end_pos) != used_sectors.end() && !std::next(end_pos)->second) {
  446. end_pos++;
  447. }
  448. if (start_pos->first < end_pos->first) {
  449. used_sectors.erase(start_pos, end_pos);
  450. }
  451. }
  452. // Restores the given log_entry's data from dest -> source
  453. // If that entry is a log sector, set the magic to kPartialRestoreMagic and flush.
  454. void restoreSector(int device_fd, Used_Sectors& used_sectors, std::vector<char>& ls_buffer,
  455. log_entry* le, std::vector<char>& buffer) {
  456. log_sector_v1_0& ls = *reinterpret_cast<log_sector_v1_0*>(&ls_buffer[0]);
  457. uint32_t index = le - ((log_entry*)&ls_buffer[ls.header_size]);
  458. int count = (le->size - 1) / kSectorSize + 1;
  459. if (checkCollision(used_sectors, le->source, le->source + count)) {
  460. fsync(device_fd);
  461. lseek64(device_fd, 0, SEEK_SET);
  462. ls.count = index + 1;
  463. ls.magic = kPartialRestoreMagic;
  464. write(device_fd, &ls_buffer[0], ls.block_size);
  465. fsync(device_fd);
  466. used_sectors.clear();
  467. used_sectors[0] = false;
  468. }
  469. markUsed(used_sectors, le->dest, le->dest + count);
  470. if (index == 0 && ls.sequence != 0) {
  471. log_sector_v1_0* next = reinterpret_cast<log_sector_v1_0*>(&buffer[0]);
  472. if (next->magic == kMagic) {
  473. next->magic = kPartialRestoreMagic;
  474. }
  475. }
  476. lseek64(device_fd, le->source * kSectorSize, SEEK_SET);
  477. write(device_fd, &buffer[0], le->size);
  478. if (index == 0) {
  479. fsync(device_fd);
  480. }
  481. }
  482. // Read from the device
  483. // If we are validating, the read occurs as though the relocations had happened
  484. std::vector<char> relocatedRead(int device_fd, Relocations const& relocations, bool validating,
  485. sector_t sector, uint32_t size, uint32_t block_size) {
  486. if (!validating) {
  487. std::vector<char> buffer(size);
  488. lseek64(device_fd, sector * kSectorSize, SEEK_SET);
  489. read(device_fd, &buffer[0], size);
  490. return buffer;
  491. }
  492. std::vector<char> buffer(size);
  493. for (uint32_t i = 0; i < size; i += block_size, sector += block_size / kSectorSize) {
  494. auto relocation = --relocations.upper_bound(sector);
  495. lseek64(device_fd, (sector + relocation->second - relocation->first) * kSectorSize,
  496. SEEK_SET);
  497. read(device_fd, &buffer[i], block_size);
  498. }
  499. return buffer;
  500. }
  501. } // namespace
  502. Status cp_restoreCheckpoint(const std::string& blockDevice, int restore_limit) {
  503. bool validating = true;
  504. std::string action = "Validating";
  505. int restore_count = 0;
  506. for (;;) {
  507. Relocations relocations;
  508. relocations[0] = 0;
  509. Status status = Status::ok();
  510. LOG(INFO) << action << " checkpoint on " << blockDevice;
  511. base::unique_fd device_fd(open(blockDevice.c_str(), O_RDWR | O_CLOEXEC));
  512. if (device_fd < 0) {
  513. PLOG(ERROR) << "Cannot open " << blockDevice;
  514. return Status::fromExceptionCode(errno, ("Cannot open " + blockDevice).c_str());
  515. }
  516. log_sector_v1_0 original_ls;
  517. read(device_fd, reinterpret_cast<char*>(&original_ls), sizeof(original_ls));
  518. if (original_ls.magic == kPartialRestoreMagic) {
  519. validating = false;
  520. action = "Restoring";
  521. } else if (original_ls.magic != kMagic) {
  522. LOG(ERROR) << "No magic";
  523. return Status::fromExceptionCode(EINVAL, "No magic");
  524. }
  525. LOG(INFO) << action << " " << original_ls.sequence << " log sectors";
  526. for (int sequence = original_ls.sequence; sequence >= 0 && status.isOk(); sequence--) {
  527. auto ls_buffer = relocatedRead(device_fd, relocations, validating, 0,
  528. original_ls.block_size, original_ls.block_size);
  529. log_sector_v1_0& ls = *reinterpret_cast<log_sector_v1_0*>(&ls_buffer[0]);
  530. Used_Sectors used_sectors;
  531. used_sectors[0] = false;
  532. if (ls.magic != kMagic && (ls.magic != kPartialRestoreMagic || validating)) {
  533. LOG(ERROR) << "No magic!";
  534. status = Status::fromExceptionCode(EINVAL, "No magic");
  535. break;
  536. }
  537. if (ls.block_size != original_ls.block_size) {
  538. LOG(ERROR) << "Block size mismatch!";
  539. status = Status::fromExceptionCode(EINVAL, "Block size mismatch");
  540. break;
  541. }
  542. if ((int)ls.sequence != sequence) {
  543. LOG(ERROR) << "Expecting log sector " << sequence << " but got " << ls.sequence;
  544. status = Status::fromExceptionCode(
  545. EINVAL, ("Expecting log sector " + std::to_string(sequence) + " but got " +
  546. std::to_string(ls.sequence))
  547. .c_str());
  548. break;
  549. }
  550. LOG(INFO) << action << " from log sector " << ls.sequence;
  551. for (log_entry* le =
  552. reinterpret_cast<log_entry*>(&ls_buffer[ls.header_size]) + ls.count - 1;
  553. le >= reinterpret_cast<log_entry*>(&ls_buffer[ls.header_size]); --le) {
  554. // This is very noisy - limit to DEBUG only
  555. LOG(VERBOSE) << action << " " << le->size << " bytes from sector " << le->dest
  556. << " to " << le->source << " with checksum " << std::hex
  557. << le->checksum;
  558. auto buffer = relocatedRead(device_fd, relocations, validating, le->dest, le->size,
  559. ls.block_size);
  560. uint32_t checksum = le->source / (ls.block_size / kSectorSize);
  561. for (size_t i = 0; i < le->size; i += ls.block_size) {
  562. crc32(&buffer[i], ls.block_size, &checksum);
  563. }
  564. if (le->checksum && checksum != le->checksum) {
  565. LOG(ERROR) << "Checksums don't match " << std::hex << checksum;
  566. status = Status::fromExceptionCode(EINVAL, "Checksums don't match");
  567. break;
  568. }
  569. if (validating) {
  570. relocate(relocations, le->source, le->dest, (le->size - 1) / kSectorSize + 1);
  571. } else {
  572. restoreSector(device_fd, used_sectors, ls_buffer, le, buffer);
  573. restore_count++;
  574. if (restore_limit && restore_count >= restore_limit) {
  575. LOG(WARNING) << "Hit the test limit";
  576. status = Status::fromExceptionCode(EAGAIN, "Hit the test limit");
  577. break;
  578. }
  579. }
  580. }
  581. }
  582. if (!status.isOk()) {
  583. if (!validating) {
  584. LOG(ERROR) << "Checkpoint restore failed even though checkpoint validation passed";
  585. return status;
  586. }
  587. LOG(WARNING) << "Checkpoint validation failed - attempting to roll forward";
  588. auto buffer = relocatedRead(device_fd, relocations, false, original_ls.sector0,
  589. original_ls.block_size, original_ls.block_size);
  590. lseek64(device_fd, 0, SEEK_SET);
  591. write(device_fd, &buffer[0], original_ls.block_size);
  592. return Status::ok();
  593. }
  594. if (!validating) break;
  595. validating = false;
  596. action = "Restoring";
  597. }
  598. return Status::ok();
  599. }
  600. Status cp_markBootAttempt() {
  601. std::string oldContent, newContent;
  602. int retry = 0;
  603. struct stat st;
  604. int result = stat(kMetadataCPFile.c_str(), &st);
  605. // If the file doesn't exist, we aren't managing a checkpoint retry counter
  606. if (result != 0) return Status::ok();
  607. if (!android::base::ReadFileToString(kMetadataCPFile, &oldContent)) {
  608. PLOG(ERROR) << "Failed to read checkpoint file";
  609. return Status::fromExceptionCode(errno, "Failed to read checkpoint file");
  610. }
  611. std::string retryContent = oldContent.substr(0, oldContent.find_first_of(" "));
  612. if (!android::base::ParseInt(retryContent, &retry))
  613. return Status::fromExceptionCode(EINVAL, "Could not parse retry count");
  614. if (retry > 0) {
  615. retry--;
  616. newContent = std::to_string(retry);
  617. if (!android::base::WriteStringToFile(newContent, kMetadataCPFile))
  618. return Status::fromExceptionCode(errno, "Could not write checkpoint file");
  619. }
  620. return Status::ok();
  621. }
  622. } // namespace vold
  623. } // namespace android