From b237d76ae5d4a68bc1df3c7926d25392e9740c3c Mon Sep 17 00:00:00 2001
From: Hridya Valsaraju <hridya@google.com>
Date: Mon, 3 Feb 2020 12:33:57 -0800
Subject: [PATCH] Mount binderfs

Mount binderfs at /dev/binderfs. Also add symlinks from /dev/binder,
/dev/hwbinder and /dev/vndbinder to /dev/binderfs/binder,
/dev/binderfs/hwbinder and /dev/binderfs/vndbinder respectively.

The symlink commands will fail harmlessly on a kernel
which does not support binderfs since /dev/{binder,hwbinder,vndbinder}
devices will exist on the same.

Bug: 136497735
Bug: 148696163

Test: Cuttlefish boots on Android Common Kernel 4.19 with kernel config
CONFIG_ANDROID_BINDERFS=y.

Change-Id: I8e04340dc4622b0a3c1fc4aa6bbefcb24eefe00b
---
 rootdir/init.rc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/rootdir/init.rc b/rootdir/init.rc
index 5f4b8c3ab..9adca26c5 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -161,6 +161,19 @@ on init
     chmod 0770 /config/sdcardfs
     chown system package_info /config/sdcardfs
 
+    # Mount binderfs
+    mkdir /dev/binderfs
+    mount binder binder /dev/binderfs stats=global
+    chmod 0755 /dev/binderfs
+
+    symlink /dev/binderfs/binder /dev/binder
+    symlink /dev/binderfs/hwbinder /dev/hwbinder
+    symlink /dev/binderfs/vndbinder /dev/vndbinder
+
+    chmod 0666 /dev/binderfs/hwbinder
+    chmod 0666 /dev/binderfs/binder
+    chmod 0666 /dev/binderfs/vndbinder
+
     mkdir /mnt/secure 0700 root root
     mkdir /mnt/secure/asec 0700 root root
     mkdir /mnt/asec 0755 root system