Commit graph

331 commits

Author SHA1 Message Date
David Anderson
14ae4d1dee libsnapshot: Round compressed COW sizes to the nearest block.
This is needed to create and stack device-mapper devices. The kernel
complains (or rejects) the table otherwise.

Bug: N/A
Test: manual test
Change-Id: I2bb3e55b7d999522c4c990b4ab7c46bcb78553a8
2020-11-06 00:50:34 -08:00
David Anderson
1b9ab3f544 libsnapshot: Add an open /dev/null mode for CowWriter.
This will be used by payload_generator to estimate the COW size without
using extra storage space.

Bug: 168554689
Test: cow_api_test, ota_from_target_files
Change-Id: I095c809e7d81eff5321b86f4c6bdfb6e9467e84e
2020-11-04 20:38:50 -08:00
Treehugger Robot
f2609b2b0f Merge "libsnapshot: Only sync after labels" 2020-11-05 03:52:04 +00:00
David Anderson
c497a1c63c Merge "libsnapshot: Use the COW size from the update manifest." 2020-11-04 20:20:14 +00:00
Treehugger Robot
f6d42d45c5 Merge changes I669a03a6,Ibb774d6d
* changes:
  libsnapshot: Fix footer values and verification
  libsnapshot: Fix some minor formatting bugs
2020-11-04 04:50:42 +00:00
Daniel Rosenberg
d5bcbaa066 libsnapshot: Only sync after labels
This changes labels to belong at the end of the set of ops that they
refer to. We only sync after writing a label, or the footer, saving the
cost of syncing after ever op.

Change-Id: Iee9dd69132b8e3321eccfe1e43fa0c072a94d3bd
Bug: 172026020
Test: cow_api_test
2020-11-03 00:40:02 -08:00
Daniel Rosenberg
290b0ed4b3 libsnapshot: Fix footer values and verification
A few values in the footer were being set inconsistently. We weren't
verifying them, so it didn't matter. This adds verification and sets
them properly.

Change-Id: I669a03a6e1e87ace31775aba5b67dde9b6e5ecf5
Bug: 168829493
Test: cow_api_test
2020-11-03 00:40:02 -08:00
Daniel Rosenberg
46ef7595d0 libsnapshot: Fix some minor formatting bugs
A few minor issues snuck through code review.
Removed a debug line in cow_api_test to persist file.
Removed unused function declaration for cow writer
Switched PLOG to LOG where no errno exists.

Change-Id: Ibb774d6de518fc2a8746e4b9eefc3655c9973c30
Bug: 168554689
Test: cow_api_test
2020-11-03 00:39:45 -08:00
David Anderson
eb7eb4bef6 libsnapshot: Use the COW size from the update manifest.
When Virtual A/B Compression is enabled, the manifest contains the
predicted COW size. Use this instead of the algorithm based on the
kernel COW format.

Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I545679b4834957ff80a930d91cb44afbadebb66c
2020-11-02 13:24:16 -08:00
David Anderson
2eb7b9221b libsnapshot: Implement MapAllSnapshots and UnmapAllSnapshots.
Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I6809e226741dabcf337c3a5cfaba56afdb9edd64
2020-11-02 13:24:15 -08:00
David Anderson
f57fd97df3 libsnapshot: Add support for first-to-second-stage transitions of snapuserd.
This patch introduces the fundamentals needed to support booting off
dm-user. First, a method has been added to start snapuserd in
first-stage init. It simply forks and execs, creates a specially named
first-stage socket, then waits for requests.

Next, a new method has been added to SnapshotManager to perform a
second-stage handoff. This works by first launching a second copy of
snapuserd using init's normal service management functionality. The new
snapuserd runs alongside the original, but has correct privileges and a
correct selinux context. Next, we inspect each COW device, and if its
table uses dm-user, we replace the table with a renamed control
device. The new control device is bound to the new snapuserd.

device-mapper guarantees that such a table swap is safe. It flushes I/O
to the old table and then replaces it with the new table. Once the new
table is in place, the old dm-user control devices are automatically
destroyed. Thus, once all dm-user devices has been transitioned, the
first-stage daemon is idle and can gracefully exit.

This patch does not modify init. A few changes will be needed on top of
this patch:

(1) CreateLogicalAndSnapshotPartitions will need further changes to
start the first-stage daemon and track its pid. Additionally, it will
need to ensure the named socket file is deleted, so there is no further
IPC allowed after partitions are completed.
(2) init will need to propagate the pid to second-stage init so the
process can be killed (or signalled).
(3) first-stage snapuserd will need to gracefully exit once it has no
active handler threads.
(4) second-stage init will need to invoke the transition helper on
SnapshotMaanager, ideally as soon as feasible.

Bug: 168259959
Test: manual test
Change-Id: I54dec2edf85ed95f11ab4518eb3d7dbaf0bdcbfd
2020-11-02 13:24:05 -08:00
David Anderson
4e4cff7e46 Merge "libsnapshot: Add a tool for inspecting COW files." 2020-10-29 00:27:28 +00:00
David Anderson
5fea7df825 Merge "libsnapshot: Add a skeleton API for mapping and unmapping all snapshots." 2020-10-29 00:27:19 +00:00
David Anderson
a1a5fdc6ee Merge "libsnapshot: Stop reading ops once we reach a footer." 2020-10-29 00:27:02 +00:00
David Anderson
49a428b62e Merge changes I2b3f5b33,I464b683b,I8e97c543
* changes:
  libsnapshot: Remove the timeout on client recv().
  libsnapshot: Integrate with snapuserd.
  snapuserd: Add an API call to wait for device deletion.
2020-10-28 01:55:09 +00:00
David Anderson
3fa66c7283 libsnapshot: Add a tool for inspecting COW files.
This simple tool will dump the COW header and included ops to stdout.

Bug: N/A
Test: mm inspect_cow && inspect_cow <file>
Change-Id: I369c4a21a84c95ffc10670bd9eeb2ceccb2a56d6
2020-10-27 18:30:13 -07:00
David Anderson
07ad1b3566 libsnapshot: Add a skeleton API for mapping and unmapping all snapshots.
Bug: 168554689
Test: builds
Change-Id: I0da50275cc4d0a85bd6b176b5c1286659d51a25c
2020-10-27 18:30:13 -07:00
David Anderson
485fe695c1 libsnapshot: Stop reading ops once we reach a footer.
Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: Id8b5ba33220028c856d3761832fe231fd93e94cd
2020-10-27 18:30:13 -07:00
David Anderson
0a03a5a8ec snapuserd: Fix infinite loop when reading ops.
Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I48e62f258ef2b4c368e8237a132c802a03d7020b
2020-10-26 22:30:21 -07:00
David Anderson
a2b5d9978a libsnapshot: Add Initialize and InitializeAppend methods to ISnapshotWriter.
This is so update engine can resume from the correct label.

Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: Ib04e80e8219f954f105d5a85f86efa7bb9097579
2020-10-26 22:30:21 -07:00
David Anderson
0544f91a9a libsnapshot: Implement OpenReader for CompressedSnapshotWriter.
Bug: 168554689
Test: vts_libsnapshot_test
Test: full OTA with update_device.py
Test: incremental OTA with update_device.py
Change-Id: I3878abfd767d2e47cf8486bc2c06233da2f1ef08
2020-10-26 22:30:21 -07:00
Greg Kaiser
74b8449f58 Fix lseek() check
Since 'pos' is unsigned, we need to tweak the check.

Test: TreeHugger
Change-Id: I97dcb50fb86196b09b11ba725593e6c83c5586d9
2020-10-26 06:37:32 -07:00
David Anderson
45662c8941 Merge "snapuserd: Refactor client to allow persistent connections." 2020-10-23 22:01:42 +00:00
David Anderson
8425f6e6e6 Merge "snapuserd: Refactor daemon/server." 2020-10-23 18:33:15 +00:00
Daniel Rosenberg
323060840a Merge changes I3339d552,I126e1583,Iccc6580a
* changes:
  Add GetLastLabel and InitializeAppend
  Switch up Cow Format to be resumable
  reland: Rename Flush to Finalize
2020-10-23 11:08:46 +00:00
David Anderson
6494a8ca97 libsnapshot: Remove the timeout on client recv().
Two seconds is a bit aggressive - considering this is analagous to a
synchronous binder call, let's drop the timeout entirely.

Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I2b3f5b33f79575d72b15ed314dbcc0ad20ebd9a8
2020-10-22 22:07:25 -07:00
David Anderson
8e46846501 libsnapshot: Integrate with snapuserd.
This integrates libsnapshot with dm-user and snapuserd. Tests progress
significantly further now. Tests involving merging still fail as
snapuserd doesn't support this yet.

Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I464b683b464fe29a646f0f2823b7f4434a878614
2020-10-22 22:07:24 -07:00
David Anderson
6a1e9ca279 snapuserd: Add an API call to wait for device deletion.
This adds a new message to the daemon protocol, which waits for a device
to be deleted. The caller must ensure that the corresponding control
device is actually going away (eg, the device containing the dm-user
table entry has been deleted). Otherwise, this will hang.

This will allow libsnapshot to safely delete the cow since any
outstanding references will be closed.

This also refactors DmUserHandler so that it's freed (and removed from
the handler list) if its corresponding thread exits of its own accord.

Bug: 168554689
Test: vts_libsnapshot_test
Change-Id: I8e97c543eec84874c88795a493470e992dc476fc
2020-10-22 22:07:24 -07:00
David Anderson
fe7585a8b0 snapuserd: Refactor client to allow persistent connections.
This refactors SnapuserdClient so it retains a connection for its
lifetime. This allows SnapshotManager to ensure the daemon is running
and hold a connection open across all of its operations.

The main impetus of this change is to remove the ambiguity between first
and second-stage sockets. SnapshotManager should only ever connect to
the first-stage socket during first-stage init, or, to initiate the
"transition" step during second-stage init.

The transition steps are roughly:
 (1) Start second-stage daemon.
 (2) Load new device-mapper tables.
 (3) Connect second-stage daemon to new dm-user devices.
 (4) Activate the new tables, flushing IO to the first-stage daemon.
 (5) Send a signal to the first-stage daemon to exit.

This patch makes it easier to hold these two separate connections.

Bug: 168554689
Test: manual test
Change-Id: I51cb9adecffb19143ed685e0c33456177ec3d81f
2020-10-22 22:07:23 -07:00
David Anderson
cff35f67ad snapuserd: Refactor daemon/server.
This is in preparation for moving to a traditional client/server model
where clients stay connected and the server multiplexes multiple
connections.

Client has been renamed to DmUserClient to differentiate it from local
socket clients.

poll() responsibilities have been moved into SnapuserdServer. In
addition, the server now tracks all open clients and polls them
together with the listen socket.

SnapuserDaemon is now only responsible for signal masking. These two
classes can probably be merged together - I didn't do that here because
the patch was already large.

Bug: 168554689
Test: manual test
Change-Id: Ibc06f6287d49e832a8e25dd936ec07747a1b0555
2020-10-22 22:00:17 -07:00
Daniel Rosenberg
3d17cb9a57 Add GetLastLabel and InitializeAppend
GetLastLabel returns the last Label that a reader is confident about.
InitializeAppend starts a writer up to append data after the last given
label, assuming all later labels are not relevant data.

Change-Id: I3339d5527bae833d9293cbbc63126136b94bd976
Bug: 168829493
Test: cow_api_test
2020-10-22 21:26:27 -07:00
Daniel Rosenberg
2d2fd72502 Switch up Cow Format to be resumable
This switches up the format to alternate ops with data, followed by a
footer containing additional meta information. This allows the file to
be resumed at arbitrary points if writing gets interrupted by power
loss.
Also adds a label op, which allows labeling future ops as connected.
If the footer is missing, Append will treat the last label as possibly
corrupt, and ignore it.

Change-Id: I126e15837d710776f9396e7afc9b0cd595e26b59
Bug: 168829493
Test: cow_api_test
2020-10-22 21:26:27 -07:00
Daniel Rosenberg
b4a81ccd5a reland: Rename Flush to Finalize
As we change to a more resumable format, flush mostly writes the final
parts of the file that are needed, which would write extra data that is
not needed to continue writing, and would immediately be overwritten.

Additionally, in the next patch we will fsync the file after adding an
op, making the flush built in, and the Finalize name more appropriate.

Bug: 168829493
Test: builds
Change-Id: Iccc6580ac72ff066cfeeb32e3cdaf69c5ba615fc
2020-10-22 02:34:26 -07:00
David Anderson
26878da29b libsnapshot: Add .rc file for snapuserd.
Bug: 168554689
Test: setprop ctl.start snapuserd
Change-Id: I9b8f20a364249135a1edb0ee69f039059c4deaf3
2020-10-21 00:41:45 -07:00
David Anderson
7d66a60012 Merge "libsnapshot: Add a source_partition parameter to OpenSnapshotWriter." 2020-10-21 06:55:03 +00:00
Daniel Rosenberg
bc7a365bbe Merge "Revert "Rename Flush to Finalize"" 2020-10-21 03:50:40 +00:00
Jason Chiu
ebfbf7d920 Revert "Rename Flush to Finalize"
This reverts commit 6177f6f6c4.

Reason for revert: Droidcop-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=aosp-master&target=sdk_x86-sdk&lkgb=6919873&lkbb=6919923&fkbb=6919923, bug b/171353958

Change-Id: Iea3059b4bf64a7cac930c40b8b312b5b26b0baea
BUG: 168829493
2020-10-21 03:16:42 +00:00
Daniel Rosenberg
6b6a2b9442 Merge "Rename Flush to Finalize" 2020-10-21 02:38:10 +00:00
David Anderson
862b01746e Merge "libsnapshot: Implement OpenSnapshotWriter for compressed snapshots." 2020-10-20 19:16:58 +00:00
David Anderson
f70d801d4b Merge "libsnapshot: Implement OnlineKernelSnapshotWriter::OpenReader." 2020-10-19 20:58:55 +00:00
Daniel Rosenberg
6177f6f6c4 Rename Flush to Finalize
As we change to a more resumable format, flush mostly writes the final
parts of the file that are needed, which would write extra data that is
not needed to continue writing, and would immediately be overwritten.

Additionally, in the next patch we will fsync the file after adding an
op, making the flush built in, and the Finalize name more appropriate.

Change-Id: I1db48315dec097b0620a0dfe7e7fd0098610d482
Bug: 168829493
Test: builds
2020-10-16 22:35:46 -07:00
Akilesh Kailash
b03e4cdccd Integrate snapuserd with dm-user ABI changes.
Create loopback device to simulate system_a/product_a partitions
to test IO path.

Bug: 168259959
Test: cow_snapuserd_test

Signed-off-by: Akilesh Kailash <akailash@google.com>
Change-Id: I9f2a311d3eccfa20c82d0ebdb3e028ea3323a48d
2020-10-17 00:41:44 +00:00
David Anderson
3feb3237c0 libsnapshot: Add a source_partition parameter to OpenSnapshotWriter.
Reading from the base device is incorrect, because if the partition
shrinks, we may still have copy operations from the removed area in the
original partition. Ask the caller to explicitly name the source device
for AddCopy() operations.

Bug: 168554689
Test: vts_libsnapshot_test
Test: full OTA with update_device.py
Test: incremental OTA with update_device.py
Change-Id: If388e37c2a2f9288a43d2849312c921bf59d4918
2020-10-14 21:42:03 -07:00
David Anderson
767f3f7216 libsnapshot: Implement OpenSnapshotWriter for compressed snapshots.
This does not implement OpenReader() yet, however, it implements enough
for some vts_libsnapshot_tests to start passing with Virtual A/B
Compression enabled.

Note that OpenSnapshotWriter() has been disabled when linking with init
or recovery. This is to avoid pulling in all the compression libraries
in those places. OpenSnapshotWriter is only designed to be called by
update_engine and will not work outside of normal operation.

Bug: 168554689
Test: vts_libsnapshot_test
Test: full OTA with update_device.py
Test: incremental OTA with update_device.py
Change-Id: I9737d28bdd5c5f4914bc30a2bb72f357d5f44d2b
2020-10-14 21:41:37 -07:00
David Anderson
3e68bd331e libsnapshot: Implement OnlineKernelSnapshotWriter::OpenReader.
Bug: 168554689
Test: vts_libsnapshot_test
Test: full OTA with update_device.py
Test: incremental OTA with update_device.py
Change-Id: Ic5eb99be8ab1f89070a0db231d4660e123ae3967
2020-10-14 21:41:37 -07:00
David Anderson
aca0beaf77 libsnapshot: Partially implement OpenSnapshotWriter.
This is a re-landing of the original CL, with a few changes:
 - The correct device is now returned in MapUpdateSnapshot.
 - The old API is used for tests, and the new API is only tested when
   used on a VABC device.
 - A sync() call has been added to ensure that writes to the base and
   target snapshot devices have been fully flushed. This makes
   IsPartitionUnchanged detect the MapUpdateSnapshot bug.

Implement OpenSnapshotWriter for non-compressed Virtual A/B. This is
done by adding an OnlineKernelSnapshotWriter class, which forwards all
writes to a dm-snapshot block device.

This also introduces a new ISnapshotWriter class which extends
ICowWriter, and adds features specific to libsnapshot (versus ICowWriter
which is intended only for the new COW format). The OpenSnapshotReader
call has been moved here since the writer retains all the information
needed to create the reader.

To test the new call, vts_libsnapshot_test has been modified to use
OpenSnapshotWriter.

As part of this change, all consumers of libsnapshot must now link to
libsnapshot_cow.

Bug: 168554689
Test: vts_libsnapshot_test
Test: full OTA with update_device.py
Test: incremental OTA with update_device.py
Change-Id: I90364a58902a4406a37cb14a816642c57a72bec2
2020-10-14 21:41:36 -07:00
Akilesh Kailash
c81477c5e4 Merge "libsnapshot:snapuserd: Handle signals" 2020-10-08 02:49:04 +00:00
Akilesh Kailash
f594785a26 libsnapshot:snapuserd: Handle signals
1: poll events to accept client request.
2: Mask all signals except SIGINT and SIGTERM.

Bug: 168258493
Test: cow_snapuserd_test

Signed-off-by: Akilesh Kailash <akailash@google.com>
Change-Id: I330170ac15199d2a97cc3b752dbf3b62b7b51a40
2020-10-07 21:45:45 +00:00
Dan Shi
67b7dd570f Remove vts10 related configs
Bug: 169582597
Test: build
Change-Id: I38e1e0f8e32b86ab14b905d040c1c62245a1a9e3
2020-10-06 13:52:44 -07:00
Tianjie Xu
216ce0985f Merge changes from topic "revert-1433573-vab-libsnapshot-linkage-APIHERUSEB"
* changes:
  Revert "libsnapshot: Partially implement OpenSnapshotWriter."
  Revert "libsnapshot: Implement OnlineKernelSnapshotWriter::OpenReader."
2020-10-03 19:27:32 +00:00