RK Android10/11/12平台上新建分区并挂载到root根目录下的方法

在根目录下创建test_dir目录

system/core$ git diff
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 24b3999..71297fb 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -139,6 +139,7 @@ LOCAL_POST_INSTALL_CMD += ; ln -sf /vendor/odm/overlay $(TARGET_ROOT_OUT)/odm/ov
 LOCAL_POST_INSTALL_CMD += ; ln -sf /vendor/odm/priv-app $(TARGET_ROOT_OUT)/odm/priv-app
 LOCAL_POST_INSTALL_CMD += ; ln -sf /vendor/odm/usr $(TARGET_ROOT_OUT)/odm/usr
 
+  LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/test_dir
 ifdef BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE
   LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/cache

给test_dir添加权限

device/rockchip/common$ git diff
diff --git a/sepolicy/private/file_contexts b/sepolicy/private/file_contexts
index d0b1d91..af22da1 100644
--- a/sepolicy/private/file_contexts
+++ b/sepolicy/private/file_contexts
@@ -1,2 +1,3 @@
 # file in /system
 /system/bin/move_widevine_data\.sh              u:object_r:move-widevine-data-sh_exec:s0
+/test_dir(/.*)?                u:object_r:cache_file:s0

在fstab下添加新分区，挂在为ext4文件系统

首先找到(或指定)fstab的模板文件：

get_build_var PRODUCT_FSTAB_TEMPLATE

例如：

PRODUCT_FSTAB_TEMPLATE := device/rockchip/common/scripts/fstab_tools/fstab.in

device/rockchip/common$ git diff
diff --git a/scripts/fstab_tools/fstab.in b/scripts/fstab_tools/fstab.in
index 2ec6c265..d823c46d 100755
--- a/scripts/fstab_tools/fstab.in
+++ b/scripts/fstab_tools/fstab.in
@@ -10,6 +10,7 @@ ${_block_prefix}odm     /odm      ext4 ro,barrier=1 ${_flags},first_stage_mount
 /dev/block/by-name/cache    /cache      ext4 noatime,nodiratime,nosuid,nodev,noauto_da_alloc,discard    wait,check
 /dev/block/by-name/metadata /metadata   ext4 nodev,noatime,nosuid,discard,sync                          wait,formattable,first_stage_mount,check
 /dev/block/by-name/misc     /misc       emmc defaults     defaults
+/dev/block/by-name/test    /test_dir      ext4 noatime,nodiratime,nosuid,nodev,noauto_da_alloc,discard    wait,check
 
 /devices/platform/*usb*   auto vfat defaults      voldmanaged=usb:auto

在parameter里面添加test分区

• 在产品的BoardConfig.mk中定义：（以rk3566_r产品为例），分区大小为16M

device/rockchip/rk356x
diff --git a/rk3566_r/BoardConfig.mk b/rk3566_r/BoardConfig.mk
index 24b415f..3fcbb2b 100644
--- a/rk3566_r/BoardConfig.mk
+++ b/rk3566_r/BoardConfig.mk
@@ -37,3 +37,5 @@ ifeq ($(strip $(BOARD_USES_AB_IMAGE)), true)
   include device/rockchip/common/BoardConfig_AB.mk
   TARGET_RECOVERY_FSTAB := device/rockchip/rk356x/rk3566_r/recovery.fstab_AB
 endif
+
+BOARD_WITH_SPECIAL_PARTITIONS := test:16M

如果要添加2个分区则是：BOARD_WITH_SPECIAL_PARTITIONS := test:16M，test1:16M

• 在RebuildParameter.mk中添加BOARD_WITH_SPECIAL_PARTITIONS

device/rockchip/common/build/rockchip/RebuildParameter.mk 
+ifneq ($(strip $(BOARD_WITH_SPECIAL_PARTITIONS)), )
+partition_list := $(partition_list),$(BOARD_WITH_SPECIAL_PARTITIONS)
+endif