Adds /dev/block/by-name/<partition> symlinks
During uevent processing, some "by-name" symlinks will be created.
/dev/block/<type>/<device>/by-name/<partition>
<type> can be: platform, pci or vbd.
<device> might be: soc.0/f9824900.sdhci, soc.0/f9824900.sdhci, etc.
<partition> might be: system, vendor, system_a, system_b, etc.
e.g., on a non-A/B device:
/dev/block/platform/soc.0/f9824900.sdhci/by-name/system
/dev/block/platform/soc.0/f9824900.sdhci/by-name/vendor
On a A/B device:
/dev/block/platform/soc/1da4000.ufshc/by-name/system_a
/dev/block/platform/soc/1da4000.ufshc/by-name/system_b
/dev/block/platform/soc/1da4000.ufshc/by-name/vendor_a
/dev/block/platform/soc/1da4000.ufshc/by-name/vendor_b
However, those symlinks are "device-specific".
This change adds the "generic" symlinks in ueventd, in addition to
the existing symlinks, when the possible "boot devices" are specified
in device tree. e.g.,
&firmware_android {
compatible = "android,firmware";
boot_devices ="soc/1da4000.ufshc,soc.0/f9824900.sdhci";
}
The following symlinks will then be created on the aforementioned non-A/B
and A/B devices, respectively.
/dev/block/by-name/system
/dev/block/by-name/vendor
/dev/block/by-name/system_a
/dev/block/by-name/system_b
/dev/block/by-name/vendor_a
/dev/block/by-name/vendor_b
Note that both <type> and <device> are skipped in the newly create symlinks.
It assumes there is no more than one devices with the same <partition>,
which is the assumption of current first stage mount flow.
Finally, when 'boot_devices' in DT is absent, it fallbacks to extract
'boot_devices' from fstab settings. e.g., using 'soc/1da4000.ufshc',
'soc.0/f9824900.sdhci' for a fstab with the following content:
/dev/block/platform/soc/1da4000.ufshc/by-name/system
/dev/block/platform/soc.0/f9824900.sdhci/by-name/vendor
Bug: 78613232
Test: adb shell ls /dev/block/by-name
Change-Id: Iec920b5a72409b6a2bdbeeb290f0a3acd2046b5d
diff --git a/init/ueventd.cpp b/init/ueventd.cpp
index 1435d82..a284203 100644
--- a/init/ueventd.cpp
+++ b/init/ueventd.cpp
@@ -30,6 +30,7 @@
#include <android-base/chrono_utils.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
+#include <fstab/fstab.h>
#include <selinux/android.h>
#include <selinux/selinux.h>
@@ -242,8 +243,9 @@
std::string hardware = android::base::GetProperty("ro.hardware", "");
parser.ParseConfig("/ueventd." + hardware + ".rc");
+ auto boot_devices = fs_mgr_get_boot_devices();
return DeviceHandler(std::move(dev_permissions), std::move(sysfs_permissions),
- std::move(subsystems), true);
+ std::move(subsystems), std::move(boot_devices), true);
}
int ueventd_main(int argc, char** argv) {