dev.mnt. properties are primarily intended for tuning parameters for
mounts such as /system and /data but don't have much use for emulated
mounts.
There are additional emulated mounts created for each user on a
device, so if too many users are created, init would otherwise create
too many dev.mnt. properties, filling the property file that backs
these properties, and preventing more properties from being
generated.
Therefore, this change stops init from creating dev.mnt. properties
for emulated mounts.
Bug: 156721033
Test: user creation stress test doesn't create large numbers of
properties
Change-Id: I6475956719b7c938b8289189abfef661140d526d
Init is no longer a special case and talks to property service just
like every other client, therefore move it away from property_set()
and to android::base::SetProperty().
In doing so, this change moves the initial property set up from the
kernel command line and property files directly into PropertyInit().
This makes the responsibilities between init and property services
more clear.
Test: boot, unit test cases
Change-Id: I36b8c83e845d887f1b203355c2391ec123c3d05f
Android-base has an implementation of the future std::expected<>.
This provides the same baseline functionality as Result<>, so use it
instead of our own version.
Bug: 132145659
Test: boot, init unit tests
Change-Id: I11e61bcb5719b262a6420483ed51a762826a9e23
On marlin, dev.mnt.blk.root is empty. Issue is shared for all
devices that are system-as-root.
/dev/root /proc/mounts entry exists before the associated block device
is instantiated by ueventd. As a result when the device shows up the
root mount is updated late when the next mount inotify trigger occurs,
delay which we will accept. But the property entries are added before
removed in the loop which causes the ultimate property entry for root
to report empty. Add /dev/block/dm-0, remove /dev/root, for property
dev.mnt.blk.root.
Fix is to change to Remove before Adding. Remove /dev/root, then add
/dev/block/dm-0.
On system-as-root as well, can not just use fstab. Determine if a
dm-verity reference is wrapped around system and use that instead.
Add some additional filtration of loop and APEX mounts to reduce
property noise.
Fix issue with creating the std:string line holder from getline(3).
Test: manual on marlin
Bug: 124072565
Change-Id: Ief2e1a6f559cbcbc87273fc2db35c675bb972f43
Set properties dev.mnt.blk.<mount_point>=<device_block_class> for mount
and umount operations by setting up an Epoll handler to catch
EPOLLERR or EPOLLPRI signals when /proc/mounts is changed. Only
update properties associated with block devices. For the mount
point of /, use the designation of /root instead.
Can use the properties in init rc expansion like:
on property dev.mnt.blk.root=*
write /sys/block/${dev.mnt.blk.root}/queue/read_ahead_kb ${boot_read_ahead_kb:-2048}
on property dev.mnt.blk.data=*
write /sys/block/${dev.mnt.blk.data}/queue/read_ahead_kb ${boot_read_ahead_kb:-2048}
on late-fs
setprop boot_read_ahead_kb 128
write /sys/block/${dev.mnt.blk.root}/queue/read_ahead_kb ${boot_read_ahead_kb}
write /sys/block/${dev.mnt.blk.data}/queue/read_ahead_kb ${boot_read_ahead_kb}
Test: boot and inspect getprop results.
Bug: 124072565
Change-Id: I1b8aff44f922ba372cd926de2919c215c40ee874
