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
The group_indices variable was intended to facilitate this, but I forgot
to actually use it.
Bug: 116817738
Test: lpmake, lpdump super_empty.img
Change-Id: Ia0da50b56b6c09e277324ec9d7aea6ce48fdc10a
Now that backup metadata is stored at the start of the super partition,
this field is no longer needed. In actuality, it was not needed even
before then: both it and first_logical_sector exist for convenience,
since they can be re-derived at any time given an LpMetadataGeometry.
Bug: 116802789
Test: liblp_test gtest
device with dynamic partitions flashes and boots
Change-Id: I259a443097e689a0a9db7f822bbf1a52d40076dc
There's no reason to do this, since the fields are already in
LpMetadataGeometry. Removing this also simplifies multiple-block-device
support.
Bug: 116802789
Test: liblp_test gtest
Change-Id: Ib244a98fdd9d36c94a2dffd81bef68a1d5644ab9
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
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
MetadataBuilder::AllocatableSpace() represents the total space
available. Adding MetadataBuilder::UsedSpace() to represent the
space used by the existing set of partitions. This will allow a
caller to predict if a partition can be resized (Grown), or to
create a partition to use up the free space (i.e. scratch).
Test: gTest liblp.UseAllDiskSpace
Bug: 109821005
Change-Id: Iae487d869fe18310c76b48c4281f1d6c1ee333cd
When adding extents to partitions, if the previous extent and new extent
are contiguous, merge them together to avoid allocating unnecessary
device-mapper targets.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I80087df9aea8141c5e16f8d4cdb3dd7da02aee8c
This logs when partition tables update, when partitions resize, and when
partitions are unmapped from device mapper.
Bug: N/A
Test: N/A
Change-Id: I1125332c79fccc3ebc556b3b48856901e2503c47
DM_TABLE_LOAD will reject dm-linear entries if their size is not a
multiple of the backing device's logical block size. For example, a
partition of 10GiB+512 bytes will fail to map in device-mapper if the
logical block size is 4096 bytes. To address this, this patch adds a
few changes to liblp:
The block size given to lpmake is now recorded in LpGeometryMetadata.
The block size must be a multiple of the sector size. In addition,
partiton sizes are now aligned to the block size, and the super
partition must have enough free space to allocate at least one block (in
addition to storing metadata).
GrowPartition now has multiple checks that the block-size invariant is not
violated, to ensure that no invalid partition tables will be created.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I484aac1f9b90ebd92dc1c89ce1e09cd89bbb441e
The partition resize algorithm duplicates a lot of logic because it
handles the final free interval separately from other free intervals.
This is unnecessary and makes it harder to change the actual algorithm.
This change makes GrowPartition() treat the final free space region the
same as free gaps in between partitions. It does this by converting the
extent list into a gap list, and then adds a final gap for the remainder
of the free space. The resize function no longer has to treat the end of
the disk separately.
This patch does not change the way partitions are allocated, it is
purely a refactoring.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I4780f20b23fe021eac62de874b061857712c04fe
This change is to assist with implementing the fastbootd "resize-partition"
command. The GrowPartition and ShrinkPartition functions are now
private.
Bug: 78793464
Test: N/A
Change-Id: Ic66a3052359e2558663272ff6e014704206b197e
This makes offset calculations and library interactions much easier.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I595c5435bd6bc166693a434ecdcd2d098185f963
This makes it easier to validate the device and make assumptions about
the device layout without having actual access.
Bug: 79173901
Test: liblp_test gtest
Change-Id: I53d24684020ec9210c8a17d155e738b3b2405806
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
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
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
