1 /*
2 * Copyright (C) 2021 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
17 #include "checkpoint_handling.h"
18 #include "log.h"
19
20 #include <fstab/fstab.h>
21 #include <unistd.h>
22 #include <cstring>
23 #include <string>
24
25 #include <libgsi/libgsi.h>
26
27 namespace {
28
29 bool checkpointingDoneForever = false;
30
31 } // namespace
32
is_data_checkpoint_active(bool * active)33 int is_data_checkpoint_active(bool* active) {
34 if (!active) {
35 ALOGE("active out parameter is null");
36 return 0;
37 }
38
39 *active = false;
40
41 if (checkpointingDoneForever) {
42 return 0;
43 }
44
45 android::fs_mgr::Fstab procMounts;
46 bool success = android::fs_mgr::ReadFstabFromFile("/proc/mounts", &procMounts);
47 if (!success) {
48 ALOGE("Could not parse /proc/mounts\n");
49 /* Really bad. Tell the caller to abort the write. */
50 return -1;
51 }
52
53 android::fs_mgr::FstabEntry* dataEntry =
54 android::fs_mgr::GetEntryForMountPoint(&procMounts, "/data");
55 if (dataEntry == NULL) {
56 ALOGE("/data is not mounted yet\n");
57 return 0;
58 }
59
60 /* We can't handle e.g., ext4. Nothing we can do about it for now. */
61 if (dataEntry->fs_type != "f2fs") {
62 ALOGW("Checkpoint status not supported for filesystem %s\n", dataEntry->fs_type.c_str());
63 checkpointingDoneForever = true;
64 return 0;
65 }
66
67 /*
68 * The data entry looks like "... blah,checkpoint=disable:0,blah ...".
69 * checkpoint=disable means checkpointing is on (yes, arguably reversed).
70 */
71 size_t checkpointPos = dataEntry->fs_options.find("checkpoint=disable");
72 if (checkpointPos == std::string::npos) {
73 /* Assumption is that once checkpointing turns off, it stays off */
74 checkpointingDoneForever = true;
75 } else {
76 *active = true;
77 }
78
79 return 0;
80 }
81
82 /**
83 * is_gsi_running() - Check if a GSI image is running via DSU.
84 *
85 * This function is equivalent to android::gsi::IsGsiRunning(), but this API is
86 * not yet vendor-accessible although the underlying metadata file is.
87 *
88 */
is_gsi_running()89 bool is_gsi_running() {
90 /* TODO(b/210501710): Expose GSI image running state to vendor storageproxyd */
91 return !access(android::gsi::kGsiBootedIndicatorFile, F_OK);
92 }
93