fs_mgr: add overlayfs handling for squashfs system filesystems
/cache/overlay directory in support of overlayfs mounts on userdebug
and eng devices. Overlayfs in turn can be capable of supporting
adb remount for read-only or restricted-storage filesystems like
squashfs or right-sized (zero free space) system partitions
respectively.
Test: compile
Bug: 109821005
Bug: 110985612
Change-Id: I3ece03886db7cc97f864497cf93ec6c6c39bccd1
diff --git a/private/file_contexts_overlayfs b/private/file_contexts_overlayfs
new file mode 100644
index 0000000..00902c2
--- /dev/null
+++ b/private/file_contexts_overlayfs
@@ -0,0 +1,6 @@
+#############################
+# Overlayfs support directories for userdebug/eng devices
+#
+/cache/overlay/(system|product)/upper u:object_r:system_file:s0
+/cache/overlay/(vendor|odm)/upper u:object_r:vendor_file:s0
+/cache/overlay/oem/upper u:object_r:vendor_file:s0