1// Copyright (C) 2019 The Android Open Source Project
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//      http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15syntax = "proto3";
16package android.snapshot;
17
18option optimize_for = LITE_RUNTIME;
19
20// Next: 4
21enum SnapshotState {
22    // No snapshot is found.
23    NONE = 0;
24
25    // The snapshot has been created and possibly written to. Rollbacks are
26    // possible by destroying the snapshot.
27    CREATED = 1;
28
29    // Changes are being merged. No rollbacks are possible beyond this point.
30    MERGING = 2;
31
32    // Changes have been merged, Future reboots may map the base device
33    // directly.
34    MERGE_COMPLETED = 3;
35}
36
37// Next: 9
38message SnapshotStatus {
39    // Name of the snapshot. This is usually the name of the snapshotted
40    // logical partition; for example, "system_b".
41    string name = 1;
42
43    SnapshotState state = 2;
44
45    // Size of the full (base) device.
46    uint64 device_size = 3;
47
48    // Size of the snapshot. This is the sum of lengths of ranges in the base
49    // device that needs to be snapshotted during the update.
50    // This must be less than or equal to |device_size|.
51    // This value is 0 if no snapshot is needed for this device because
52    // no changes
53    uint64 snapshot_size = 4;
54
55    // Size of the "COW partition". A COW partition is a special logical
56    // partition represented in the super partition metadata. This partition and
57    // the "COW image" form the "COW device" that supports the snapshot device.
58    //
59    // When SnapshotManager creates a COW device, it first searches for unused
60    // blocks in the super partition, and use those before creating the COW
61    // image if the COW partition is not big enough.
62    //
63    // This value is 0 if no space in super is left for the COW partition.
64    // |cow_partition_size + cow_file_size| must not be zero if |snapshot_size|
65    // is non-zero.
66    uint64 cow_partition_size = 5;
67
68    // Size of the "COW file", or "COW image". A COW file / image is created
69    // when the "COW partition" is not big enough to store changes to the
70    // snapshot device.
71    //
72    // This value is 0 if |cow_partition_size| is big enough to hold all changes
73    // to the snapshot device.
74    uint64 cow_file_size = 6;
75
76    // Sectors allocated for the COW device. Recording this value right after
77    // the update and before the merge allows us to infer the progress of the
78    // merge process.
79    // This is non-zero when |state| == MERGING or MERGE_COMPLETED.
80    uint64 sectors_allocated = 7;
81
82    // Metadata sectors allocated for the COW device. Recording this value right
83    // before the update and before the merge allows us to infer the progress of
84    // the merge process.
85    // This is non-zero when |state| == MERGING or MERGE_COMPLETED.
86    uint64 metadata_sectors = 8;
87}
88
89// Next: 8
90enum UpdateState {
91    // No update or merge is in progress.
92    None = 0;
93
94    // An update is applying; snapshots may already exist.
95    Initiated = 1;
96
97    // An update is pending, but has not been successfully booted yet.
98    Unverified = 2;
99
100    // The kernel is merging in the background.
101    Merging = 3;
102
103    // Post-merge cleanup steps could not be completed due to a transient
104    // error, but the next reboot will finish any pending operations.
105    MergeNeedsReboot = 4;
106
107    // Merging is complete, and needs to be acknowledged.
108    MergeCompleted = 5;
109
110    // Merging failed due to an unrecoverable error.
111    MergeFailed = 6;
112
113    // The update was implicitly cancelled, either by a rollback or a flash
114    // operation via fastboot. This state can only be returned by WaitForMerge.
115    Cancelled = 7;
116};
117
118// Next: 5
119message SnapshotUpdateStatus {
120    UpdateState state = 1;
121
122    // Total number of sectors allocated in the COW files before performing the
123    // merge operation.  This field is used to keep track of the total number
124    // of sectors modified to monitor and show the progress of the merge during
125    // an update.
126    uint64 sectors_allocated = 2;
127
128    // Total number of sectors of all the snapshot devices.
129    uint64 total_sectors = 3;
130
131    // Sectors allocated for metadata in all the snapshot devices.
132    uint64 metadata_sectors = 4;
133}
134
135// Next: 4
136message SnapshotMergeReport {
137    // Status of the update after the merge attempts.
138    UpdateState state = 1;
139
140    // Number of reboots that occurred after issuing and before completeing the
141    // merge of all the snapshot devices.
142    int32 resume_count = 2;
143
144    // Total size of all the COW images before the update.
145    uint64 cow_file_size = 3;
146}
147