Traditionally the first 512 bytes of a partition can be interpreted as
an MBR. To prevent any compatibility issues, we explicitly zero the
first 4096 bytes of the super partition (one logical block, on most
systems).
Bug: 116802789
Test: liblp_test gtest
device with super partition flashes and boots
Change-Id: I29688ca75dbb52442f1464e8ab35893678a4f79e
Previously, metadata backups were stored at the end of the partition to
make them easy to locate. On older devices where the super partition
could span system/vendor partitions, we may want to leave the end of
each partition free to store an AVB footer. To allow this, we now store
geometry and metadata backups near the start of the partition instead.
They are still positioned at a fixed offset.
Bug: 116802789
Test: device boots after flashing new metadata
Change-Id: Ib173f251a4a13e290adcc4ac5cfbeb030eacda30
Note that this moves SparseBuilder into images.h, and splits
ReadLogicalPartitionGeometry into componenet methods for better
testability.
Bug: 116802789
Test: liblp_test gtest
Change-Id: Ib41a46b633c71623c136a10fcc8017e4de20884c
This patch introduces a new "groups" table in the super partition
metadata. Each entry denotes a named partition group with a maximum
size. All partitions now belong to a group, and the total size of
partitions in a group must not exceed its maximum size. This is enforced
by MetadataBuilder.
There is also a "default" group with no size restriction. This is used
for one-off partitions that aren't restricted by updates, for example,
the scratch partition for overlayfs, or partitions created through
fastbootd.
Bug: 116817738
Test: liblp gtest
Change-Id: I7049ffd35d326e41e25d01b1748cb53a584783a7
This change enables reading metadata images from memory, for situations
where using file descriptors is not practical (such as fastbootd flash).
Bug: 78793464
Test: liblp_test gtest
Change-Id: I9ad08b0ddd4cbb96e87583237a90785e0f4befa4
This is in preparation for "fastboot flash super", where we want to
verify the validity of a super image before writing it. To do so, we
need to parse the image from the download buffer, and it is useful to do
this from memory rather than a file descriptor.
Bug: 78793464
Test: liblp_test gtest
Change-Id: I7fb1ef4fdf2e8f1d93aea38f75626157fcb4bfc1
Callers of ParseMetadata must manually copy geometry to the final
LpMetadata structure, which is error-prone. Instead, force callers to
pass geometry to ParseMetadata to ensure it is always propagated.
Bug: N/A
Test: liblp_test gtest
Change-Id: I5b24b9d94ab1857db600c40bf6d3c9d8aaa47368
This is in preparation for adding sparse image support, to avoid
cluttering the more critical reading and writing logic.
Bug: 79173901
Test: N/A
Change-Id: Icdddb849aebba4adf18a3e63ffbd3f36adda812d
This makes offset calculations and library interactions much easier.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I595c5435bd6bc166693a434ecdcd2d098185f963
This changes reader.h and writer.h to be private includes. A new liblp.h
header now contains the public API surface of those two files, as well
as some miscellanious functions previously in metadata_format.h.
Bug: 79173901
Test: N/A
Change-Id: I40c5dda0c8e5765f8bccfd5c17b4c800b41be77b
If UpdatePartitionTable is interrupted while writing metadata, the next
update becomes much more risky, as only one valid copy may exist. If
that subsequent update is interrupted, all metadata copies may be
corrupt.
To alleviate this, we now synchronize both metadata copies before each
update. If the backup copy is corrupted, we replace it with the primary
copy, and vice versa. Similarly if the primary and backup metadata do
not match, we sync the backup to contain the same data as the primary.
If for some reason this synchronization process fails, we do not proceed
to write a new partition table.
Bug: 79173901
Test: liblp_test gtest
Change-Id: Ic80cf9a5dc6336ff532e069ca5c8c76371550cb9
Block devices in the Linux kernel have a "minimum I/O request" size. The
minimum size is usually acquired by the block driver and can change
from device to device. When stacking devices (such as with
device-mapper), the kernel goes through great lengths to make sure this
alignment is respected for optimal I/O. In device-mapper's case,
misalignment can lead to kernel warnings and performance issues.
While this is unlikely to matter with a few targets, it could become
problematic on a large number of targets, and so we would prefer to
align all partition extents to the minimum I/O size.
We now support two new properties in the partition table geometry: an
"alignment", which is the minimum I/O size, and an "alignment offset",
which is an offset that when applied to sector 0, causes the sector to
be properly aligned within its parent device (for example, if a
physical partition is misaligned). All partition extents now begin on a
sector that respects this alignment.
One major caveat is that it is difficult for the initial partition table
to have the correct alignment without build system and/or flash tool
support. To accomodate this, all alignment is optional, and the lpmake
tool will support a default alignment of 1MiB as a failsafe.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I5bc41b90aa085f4f30393951af0d2b37c4ac2a72
These tests check that various aspects of liblp's on-disk management
are functioning as intended. This checks redundancy, metadata slot
management, and metadata update and readback.
Bug: 79173901
Test: liblp_test gtest
Change-Id: Ib780676e0f34f44aa255e8fcfded2ceb71fe3dce
This library has methods to build, read, and modify logical partition tables
based on device-mapper targets. Targets currently supported are
dm-linear and dm-zero.
Note: this is a revert of a revert, with changes to fix Mac build
bustage.
Bug: 79173901
Test: N/A
Change-Id: If89a788d1919ce8ddc6eedaecc9687a92f111dfa
This library has methods to build, read, and modify logical partition tables
based on device-mapper targets. Targets currently supported are
dm-linear and dm-zero.
Bug: 79173901
Test: N/A
Change-Id: I194c6832cb53f781c396016d961386d3ca833f87
