Userspace reboot: Support remounting userdata for f2fs (12a36076) · Commits · e / os / android_system_core

fs_mgr/fs_mgr.cpp

+75 −7

Original line number	Diff line number	Diff line
		@@ -888,6 +888,17 @@ class CheckpointManager {
		public:
		CheckpointManager(int needs_checkpoint = -1) : needs_checkpoint_(needs_checkpoint) {}

		bool NeedsCheckpoint() {
		if (needs_checkpoint_ != UNKNOWN) {
		return needs_checkpoint_ == YES;
		}
		if (!call_vdc({"checkpoint", "needsCheckpoint"}, &needs_checkpoint_)) {
		LERROR << "Failed to find if checkpointing is needed. Assuming no.";
		needs_checkpoint_ = NO;
		}
		return needs_checkpoint_ == YES;
		}

		bool Update(FstabEntry* entry, const std::string& block_device = std::string()) {
		if (!entry->fs_mgr_flags.checkpoint_blk && !entry->fs_mgr_flags.checkpoint_fs) {
		return true;
		@@ -897,13 +908,7 @@ class CheckpointManager {
		call_vdc({"checkpoint", "restoreCheckpoint", entry->blk_device}, nullptr);
		}

		if (needs_checkpoint_ == UNKNOWN &&
		!call_vdc({"checkpoint", "needsCheckpoint"}, &needs_checkpoint_)) {
		LERROR << "Failed to find if checkpointing is needed. Assuming no.";
		needs_checkpoint_ = NO;
		}

		if (needs_checkpoint_ != YES) {
		if (!NeedsCheckpoint()) {
		return true;
		}

		@@ -1324,6 +1329,69 @@ int fs_mgr_umount_all(android::fs_mgr::Fstab* fstab) {
		return ret;
		}

		static std::string GetUserdataBlockDevice() {
		Fstab fstab;
		if (!ReadFstabFromFile("/proc/mounts", &fstab)) {
		LERROR << "Failed to read /proc/mounts";
		return "";
		}
		auto entry = GetEntryForMountPoint(&fstab, "/data");
		if (entry == nullptr) {
		LERROR << "Didn't find /data mount point in /proc/mounts";
		return "";
		}
		return entry->blk_device;
		}

		int fs_mgr_remount_userdata_into_checkpointing(Fstab* fstab) {
		const std::string& block_device = GetUserdataBlockDevice();
		LINFO << "Userdata is mounted on " << block_device;
		auto entry = std::find_if(fstab->begin(), fstab->end(), [&block_device](const FstabEntry& e) {
		if (e.mount_point != "/data") {
		return false;
		}
		if (e.blk_device == block_device) {
		return true;
		}
		DeviceMapper& dm = DeviceMapper::Instance();
		std::string path;
		if (!dm.GetDmDevicePathByName("userdata", &path)) {
		return false;
		}
		return path == block_device;
		});
		if (entry == fstab->end()) {
		LERROR << "Can't find /data in fstab";
		return -1;
		}
		if (!entry->fs_mgr_flags.checkpoint_blk && !entry->fs_mgr_flags.checkpoint_fs) {
		LINFO << "Userdata doesn't support checkpointing. Nothing to do";
		return 0;
		}
		CheckpointManager checkpoint_manager;
		if (!checkpoint_manager.NeedsCheckpoint()) {
		LINFO << "Checkpointing not needed. Don't remount";
		return 0;
		}
		if (entry->fs_mgr_flags.checkpoint_fs) {
		// Userdata is f2fs, simply remount it.
		if (!checkpoint_manager.Update(&(*entry))) {
		LERROR << "Failed to remount userdata in checkpointing mode";
		return -1;
		}
		if (mount(entry->blk_device.c_str(), entry->mount_point.c_str(), "none",
		MS_REMOUNT \| entry->flags, entry->fs_options.c_str()) != 0) {
		LERROR << "Failed to remount userdata in checkpointing mode";
		return -1;
		}
		} else {
		// TODO(b/135984674): support remounting for ext4.
		LERROR << "Remounting in checkpointing mode is not yet supported for ext4";
		return -1;
		}
		return 0;
		}

		// wrapper to __mount() and expects a fully prepared fstab_rec,
		// unlike fs_mgr_do_mount which does more things with avb / verity etc.
		int fs_mgr_do_mount_one(const FstabEntry& entry, const std::string& mount_point) {

fs_mgr/include/fs_mgr.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -105,6 +105,8 @@ enum FsMgrUmountStatus : int {
		// it destroys verity devices from device mapper after the device is unmounted.
		int fs_mgr_umount_all(android::fs_mgr::Fstab* fstab);

		int fs_mgr_remount_userdata_into_checkpointing(android::fs_mgr::Fstab* fstab);

		// Finds the dm_bow device on which this block device is stacked, or returns
		// empty string
		std::string fs_mgr_find_bow_device(const std::string& block_device);

init/builtins.cpp

+26 −0

Original line number	Diff line number	Diff line
		@@ -42,6 +42,8 @@
		#include <sys/wait.h>
		#include <unistd.h>

		#include <memory>

		#include <ApexProperties.sysprop.h>
		#include <android-base/chrono_utils.h>
		#include <android-base/file.h>
		@@ -627,6 +629,8 @@ static Result<void> queue_fs_event(int code) {
		return Error() << "Invalid code: " << code;
		}

		static int initial_mount_fstab_return_code = -1;

		/* mount_all <fstab> [ <path> ]* [--<options>]*
		*
		* This function might request a reboot, in which case it will
		@@ -662,6 +666,7 @@ static Result<void> do_mount_all(const BuiltinArguments& args) {
		if (!ReadFstabFromFile(fstab_file, &fstab)) {
		return Error() << "Could not read fstab";
		}

		auto mount_fstab_return_code = fs_mgr_mount_all(&fstab, mount_mode);
		property_set(prop_name, std::to_string(t.duration().count()));

		@@ -673,6 +678,7 @@ static Result<void> do_mount_all(const BuiltinArguments& args) {
		if (queue_event) {
		/* queue_fs_event will queue event based on mount_fstab return code
		* and return processed return code*/
		initial_mount_fstab_return_code = mount_fstab_return_code;
		auto queue_fs_result = queue_fs_event(mount_fstab_return_code);
		if (!queue_fs_result) {
		return Error() << "queue_fs_event() failed: " << queue_fs_result.error();
		@@ -1132,6 +1138,25 @@ static Result<void> ExecVdcRebootOnFailure(const std::string& vdc_arg) {
		return ExecWithFunctionOnFailure(args, reboot);
		}

		static Result<void> do_remount_userdata(const BuiltinArguments& args) {
		if (initial_mount_fstab_return_code == -1) {
		return Error() << "Calling remount_userdata too early";
		}
		Fstab fstab;
		if (!ReadDefaultFstab(&fstab)) {
		// TODO(b/135984674): should we reboot here?
		return Error() << "Failed to read fstab";
		}
		// TODO(b/135984674): check that fstab contains /data.
		if (auto rc = fs_mgr_remount_userdata_into_checkpointing(&fstab); rc < 0) {
		TriggerShutdown("reboot,mount-userdata-failed");
		}
		if (auto result = queue_fs_event(initial_mount_fstab_return_code); !result) {
		return Error() << "queue_fs_event() failed: " << result.error();
		}
		return {};
		}

		static Result<void> do_installkey(const BuiltinArguments& args) {
		if (!is_file_crypto()) return {};

		@@ -1243,6 +1268,7 @@ const BuiltinFunctionMap& GetBuiltinFunctionMap() {
		{"umount", {1, 1, {false, do_umount}}},
		{"umount_all", {1, 1, {false, do_umount_all}}},
		{"readahead", {1, 2, {true, do_readahead}}},
		{"remount_userdata", {0, 0, {false, do_remount_userdata}}},
		{"restart", {1, 1, {false, do_restart}}},
		{"restorecon", {1, kMax, {true, do_restorecon}}},
		{"restorecon_recursive", {1, kMax, {true, do_restorecon_recursive}}},

init/reboot.cpp

+38 −14

Original line number	Diff line number	Diff line
		@@ -181,10 +181,17 @@ static void TurnOffBacklight() {
		}
		}

		static void ShutdownVold() {
		static Result<void> ShutdownVold() {
		const char* vdc_argv[] = {"/system/bin/vdc", "volume", "shutdown"};
		int status;
		logwrap_fork_execvp(arraysize(vdc_argv), vdc_argv, &status, false, LOG_KLOG, true, nullptr);
		if (logwrap_fork_execvp(arraysize(vdc_argv), vdc_argv, &status, false, LOG_KLOG, true,
		nullptr) != 0) {
		return ErrnoError() << "Failed to call 'vdc volume shutdown'";
		}
		if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
		return {};
		}
		return Error() << "'vdc volume shutdown' failed : " << status;
		}

		static void LogShutdownTime(UmountStat stat, Timer* t) {
		@@ -426,11 +433,11 @@ static UmountStat TryUmountAndFsck(unsigned int cmd, const std::string& rebootTa
		#define ZRAM_DEVICE "/dev/block/zram0"
		#define ZRAM_RESET "/sys/block/zram0/reset"
		#define ZRAM_BACK_DEV "/sys/block/zram0/backing_dev"
		static void KillZramBackingDevice() {
		static Result<void> KillZramBackingDevice() {
		std::string backing_dev;
		if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) return;
		if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) return {};

		if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) return;
		if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) return {};

		// cut the last "\n"
		backing_dev.erase(backing_dev.length() - 1);
		@@ -439,28 +446,29 @@ static void KillZramBackingDevice() {
		Timer swap_timer;
		LOG(INFO) << "swapoff() start...";
		if (swapoff(ZRAM_DEVICE) == -1) {
		LOG(ERROR) << "zram_backing_dev: swapoff (" << backing_dev << ")" << " failed";
		return;
		return ErrnoError() << "zram_backing_dev: swapoff (" << backing_dev << ")"
		<< " failed";
		}
		LOG(INFO) << "swapoff() took " << swap_timer;;

		if (!WriteStringToFile("1", ZRAM_RESET)) {
		LOG(ERROR) << "zram_backing_dev: reset (" << backing_dev << ")" << " failed";
		return;
		return Error() << "zram_backing_dev: reset (" << backing_dev << ")"
		<< " failed";
		}

		// clear loopback device
		unique_fd loop(TEMP_FAILURE_RETRY(open(backing_dev.c_str(), O_RDWR \| O_CLOEXEC)));
		if (loop.get() < 0) {
		LOG(ERROR) << "zram_backing_dev: open(" << backing_dev << ")" << " failed";
		return;
		return ErrnoError() << "zram_backing_dev: open(" << backing_dev << ")"
		<< " failed";
		}

		if (ioctl(loop.get(), LOOP_CLR_FD, 0) < 0) {
		LOG(ERROR) << "zram_backing_dev: loop_clear (" << backing_dev << ")" << " failed";
		return;
		return ErrnoError() << "zram_backing_dev: loop_clear (" << backing_dev << ")"
		<< " failed";
		}
		LOG(INFO) << "zram_backing_dev: `" << backing_dev << "` is cleared successfully.";
		return {};
		}

		// Stops given services, waits for them to be stopped for \|timeout\| ms.
		@@ -738,7 +746,23 @@ static Result<void> DoUserspaceReboot() {
		// TODO(b/135984674): store information about offending services for debugging.
		return Error() << r << " post-data services are still running";
		}
		// TODO(b/135984674): remount userdata
		// We only really need to restart vold if userdata is ext4 filesystem.
		// TODO(b/135984674): get userdata fs type here, and do nothing in case of f2fs.
		// First shutdown volumes managed by vold. They will be recreated by
		// system_server.
		Service* vold_service = ServiceList::GetInstance().FindService("vold");
		if (vold_service != nullptr && vold_service->IsRunning()) {
		if (auto result = ShutdownVold(); !result) {
		return result;
		}
		LOG(INFO) << "Restarting vold";
		vold_service->Restart();
		}
		// Again, we only need to kill zram backing device in case of ext4 userdata.
		// TODO(b/135984674): get userdata fs type here, and do nothing in case of f2fs.
		if (auto result = KillZramBackingDevice(); !result) {
		return result;
		}
		if (int r = StopServicesAndLogViolations(GetDebuggingServices(true /* only_post_data */), 5s,
		false /* SIGKILL */);
		r > 0) {

rootdir/init.rc

+10 −2

Original line number	Diff line number	Diff line
		@@ -925,9 +925,17 @@ on userspace-reboot
		setprop sys.init.updatable_crashing 0
		setprop apexd.status 0

		on userspace-reboot-fs-remount
		# Make sure that vold is running.
		# This is mostly a precaution measure in case vold for some reason wasn't running when
		# userspace reboot was initiated.
		start vold
		exec - system system -- /system/bin/vdc checkpoint resetCheckpoint
		exec - system system -- /system/bin/vdc checkpoint markBootAttempt
		remount_userdata

		on userspace-reboot-resume
		# TODO(b/135984674): remount userdata and reset checkpointing
		trigger nonencrypted
		trigger userspace-reboot-fs-remount
		trigger post-fs-data
		trigger zygote-start
		trigger early-boot