Merge "Cleanup logic in KillZramBackingDevice" am: 1e98e552c6 (b0c6174a) · Commits · e / os / android_system_core

init/reboot.cpp

+14 −4

Original line number	Diff line number	Diff line
		@@ -203,6 +203,7 @@ static void TurnOffBacklight() {
		}

		static Result<void> CallVdc(const std::string& system, const std::string& cmd) {
		LOG(INFO) << "Calling /system/bin/vdc " << system << " " << cmd;
		const char* vdc_argv[] = {"/system/bin/vdc", system.c_str(), cmd.c_str()};
		int status;
		if (logwrap_fork_execvp(arraysize(vdc_argv), vdc_argv, &status, false, LOG_KLOG, true,
		@@ -456,10 +457,14 @@ static UmountStat TryUmountAndFsck(unsigned int cmd, bool run_fsck,
		#define ZRAM_RESET "/sys/block/zram0/reset"
		#define ZRAM_BACK_DEV "/sys/block/zram0/backing_dev"
		static Result<void> KillZramBackingDevice() {
		if (access(ZRAM_BACK_DEV, F_OK) != 0 && errno == ENOENT) {
		LOG(INFO) << "No zram backing device configured";
		return {};
		}
		std::string backing_dev;
		if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) return {};

		if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) return {};
		if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) {
		return ErrnoError() << "Failed to read " << ZRAM_BACK_DEV;
		}

		// cut the last "\n"
		backing_dev.erase(backing_dev.length() - 1);
		@@ -478,6 +483,11 @@ static Result<void> KillZramBackingDevice() {
		<< " failed";
		}

		if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) {
		LOG(INFO) << backing_dev << " is not a loop device. Exiting early";
		return {};
		}

		// clear loopback device
		unique_fd loop(TEMP_FAILURE_RETRY(open(backing_dev.c_str(), O_RDWR \| O_CLOEXEC)));
		if (loop.get() < 0) {