storageproxyd: discard writes when checkpointing, if necessary am: 98e7f427e8 (77b37c9f) · Commits · e / os / android_system_core

trusty/storage/interface/include/trusty/interface/storage.h

+22 −18

Original line number	Diff line number	Diff line
		@@ -115,7 +115,7 @@ enum storage_file_open_flag {
		* @STORAGE_MSG_FLAG_BATCH: if set, command belongs to a batch transaction.
		* No response will be sent by the server until
		* it receives a command with this flag unset, at
		* which point a cummulative result for all messages
		* which point a cumulative result for all messages
		* sent with STORAGE_MSG_FLAG_BATCH will be sent.
		* This is only supported by the non-secure disk proxy
		* server.
		@@ -126,12 +126,16 @@ enum storage_file_open_flag {
		* @STORAGE_MSG_FLAG_TRANSACT_COMPLETE: if set, indicates that server need to commit
		* current transaction after processing this message.
		* It is an alias for STORAGE_MSG_FLAG_POST_COMMIT.
		* @STORAGE_MSG_FLAG_PRE_COMMIT_CHECKPOINT: if set, indicates that server needs to ensure
		* that there is not a pending checkpoint for
		* userdata before processing this message.
		*/
		enum storage_msg_flag {
		STORAGE_MSG_FLAG_BATCH = 0x1,
		STORAGE_MSG_FLAG_PRE_COMMIT = 0x2,
		STORAGE_MSG_FLAG_POST_COMMIT = 0x4,
		STORAGE_MSG_FLAG_TRANSACT_COMPLETE = STORAGE_MSG_FLAG_POST_COMMIT,
		STORAGE_MSG_FLAG_PRE_COMMIT_CHECKPOINT = 0x8,
		};

		/*

trusty/storage/proxy/Android.bp

+3 −0

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@ cc_binary {
		vendor: true,

		srcs: [
		"checkpoint_handling.cpp",
		"ipc.c",
		"rpmb.c",
		"storage.c",
		@@ -30,12 +31,14 @@ cc_binary {
		],

		shared_libs: [
		"libbase",
		"liblog",
		"libhardware_legacy",
		],
		header_libs: ["libcutils_headers"],

		static_libs: [
		"libfstab",
		"libtrustystorageinterface",
		"libtrusty",
		],

trusty/storage/proxy/checkpoint_handling.cpp

0 → 100644

+77 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2021 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 "checkpoint_handling.h"
		#include "log.h"

		#include <fstab/fstab.h>
		#include <cstring>
		#include <string>

		namespace {

		bool checkpointingDoneForever = false;

		} // namespace

		int is_data_checkpoint_active(bool* active) {
		if (!active) {
		ALOGE("active out parameter is null");
		return 0;
		}

		*active = false;

		if (checkpointingDoneForever) {
		return 0;
		}

		android::fs_mgr::Fstab procMounts;
		bool success = android::fs_mgr::ReadFstabFromFile("/proc/mounts", &procMounts);
		if (!success) {
		ALOGE("Could not parse /proc/mounts\n");
		/* Really bad. Tell the caller to abort the write. */
		return -1;
		}

		android::fs_mgr::FstabEntry* dataEntry =
		android::fs_mgr::GetEntryForMountPoint(&procMounts, "/data");
		if (dataEntry == NULL) {
		ALOGE("/data is not mounted yet\n");
		return 0;
		}

		/* We can't handle e.g., ext4. Nothing we can do about it for now. */
		if (dataEntry->fs_type != "f2fs") {
		ALOGW("Checkpoint status not supported for filesystem %s\n", dataEntry->fs_type.c_str());
		checkpointingDoneForever = true;
		return 0;
		}

		/*
		* The data entry looks like "... blah,checkpoint=disable:0,blah ...".
		* checkpoint=disable means checkpointing is on (yes, arguably reversed).
		*/
		size_t checkpointPos = dataEntry->fs_options.find("checkpoint=disable");
		if (checkpointPos == std::string::npos) {
		/* Assumption is that once checkpointing turns off, it stays off */
		checkpointingDoneForever = true;
		} else {
		*active = true;
		}

		return 0;
		}

trusty/storage/proxy/checkpoint_handling.h

0 → 100644

+37 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2021 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.
		*/

		#pragma once

		#include <stdbool.h>

		#ifdef __cplusplus
		extern "C" {
		#endif

		/**
		* is_data_checkpoint_active() - Check for an active, uncommitted checkpoint of
		* /data. If a checkpoint is active, storage should not commit any
		* rollback-protected writes to /data.
		* @active: Out parameter that will be set to the result of the check.
		*
		* Return: 0 if active was set and is valid, non-zero otherwise.
		*/
		int is_data_checkpoint_active(bool* active);

		#ifdef __cplusplus
		}
		#endif

trusty/storage/proxy/proxy.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@

		#include <cutils/android_filesystem_config.h>

		#include "checkpoint_handling.h"
		#include "ipc.h"
		#include "log.h"
		#include "rpmb.h"
		@@ -130,6 +131,21 @@ static int handle_req(struct storage_msg* msg, const void* req, size_t req_len)
		}
		}

		if (msg->flags & STORAGE_MSG_FLAG_PRE_COMMIT_CHECKPOINT) {
		bool is_checkpoint_active = false;

		rc = is_data_checkpoint_active(&is_checkpoint_active);
		if (rc != 0) {
		ALOGE("is_data_checkpoint_active failed in an unexpected way. Aborting.\n");
		msg->result = STORAGE_ERR_GENERIC;
		return ipc_respond(msg, NULL, 0);
		} else if (is_checkpoint_active) {
		ALOGE("Checkpoint in progress, dropping write ...\n");
		msg->result = STORAGE_ERR_GENERIC;
		return ipc_respond(msg, NULL, 0);
		}
		}

		switch (msg->cmd) {
		case STORAGE_FILE_DELETE:
		rc = storage_file_delete(msg, req, req_len);