SW：Android11
HW：QCS6125
需求来源：
线上的设备进入recovery模式，正常缓存在data分区的日志无法获取：
1、此种情境下只能选择恢复出厂设置，但在恢复之后，data目录下的logcat日志也会被清理；2、recovery模式下无法屏蔽分区加密，处于用户数据安全考虑，无法在该模式挂载userdataimage；
鉴于此，决定重新创建一个分区，将logcat后台记录的日志文件全部移到此分区，由于此分区不参与recovery的双清操作，因此可保证系统再次启动后，该分区依然有recovery模式之前的日志文件，用来排查导致进入recovery模式的原因。我们这个分区的size定义为100M大小，这个可根据自己需要做调整。
具体操作流程如下：
1、修改common目录下的分区表文件，命名分区为jingang：
diff --git a/config/ufs/partition.xml b/config/ufs/partition.xml
index fafa0b5..f821818 100755
--- a/config/ufs/partition.xml
+++ b/config/ufs/partition.xml
@@ -19,6 +19,7 @@
<partition label="misc" size_in_kb="1024" type="82ACC91F-357C-4A68-9C8F-689E1B1A23A1" bootable="false" readonly="false" filename="" />
<partition label="keystore" size_in_kb="512" type="DE7D4029-0F5B-41C8-AE7E-F6C023A02B33" bootable="false" readonly="false" filename="" />
<partition label="frp" size_in_kb="512" type="91B72D4D-71E0-4CBF-9B8E-236381CFF17A" bootable="false" readonly="false" filename=""/>
+ <partition label="jingang" size_in_kb="102400" type="66b9d1c5-7881-4a82-8f79-22a768a52db2" bootable="false" readonly="false" filename="jingang.img" sparse="true"/>
<partition label="super" size_in_kb="6291456" type="89A12DE1-5E41-4CB3-8B4C-B1441EB5DA38" bootable="false" readonly="false" filename="super.img" sparse="true"/>
<partition label="recovery_a" size_in_kb="98304" type="D504D6DB-FA92-4853-B59E-C7F292E2EA19" bootable="false" readonly="true" filename="recovery.img" sparse="true"/>
<partition label="recovery_b" size_in_kb="98304" type="352B8083-9C0C-4BED-9917-CB5EABD64D41" bootable="false" readonly="true" filename="recovery.img" sparse="true"/>
diff --git a/config/ufs/partition_factory.xml b/config/ufs/partition_factory.xml
index 043c6a1..e16842c 100755
--- a/config/ufs/partition_factory.xml
+++ b/config/ufs/partition_factory.xml
@@ -19,6 +19,7 @@
<partition label="misc" size_in_kb="1024" type="82ACC91F-357C-4A68-9C8F-689E1B1A23A1" bootable="false" readonly="false" filename="misc.img" />
<partition label="keystore" size_in_kb="512" type="DE7D4029-0F5B-41C8-AE7E-F6C023A02B33" bootable="false" readonly="false" filename="" />
<partition label="frp" size_in_kb="512" type="91B72D4D-71E0-4CBF-9B8E-236381CFF17A" bootable="false" readonly="false" filename=""/>
+ <partition label="jingang" size_in_kb="102400" type="66b9d1c5-7881-4a82-8f79-22a768a52db2" bootable="false" readonly="false" filename="jingang.img" sparse="true"/>
<partition label="super" size_in_kb="6291456" type="89A12DE1-5E41-4CB3-8B4C-B1441EB5DA38" bootable="false" readonly="false" filename="super.img" sparse="true"/>
<partition label="recovery_a" size_in_kb="98304" type="D504D6DB-FA92-4853-B59E-C7F292E2EA19" bootable="false" readonly="true" filename="recovery.img" sparse="true"/>
<partition label="recovery_b" size_in_kb="98304" type="352B8083-9C0C-4BED-9917-CB5EABD64D41" bootable="false" readonly="true" filename="recovery.img" sparse="true"/>2、相应的缩减data分区100M大小device/qcom/trinket：
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 7ebc32a..965a83e 100755
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -153,7 +153,7 @@ BOARD_BOOTIMAGE_PARTITION_SIZE := 0x04000000
# 64G userdata
# BOARD_USERDATAIMAGE_PARTITION_SIZE := 52676079616
# 128G userdata sumsung
-BOARD_USERDATAIMAGE_PARTITION_SIZE := 116391936000
+BOARD_USERDATAIMAGE_PARTITION_SIZE := 116255621120
BOARD_PERSISTIMAGE_PARTITION_SIZE := 33554432
BOARD_DTBOIMG_PARTITION_SIZE := 0x0800000
BOARD_METADATAIMAGE_PARTITION_SIZE := 16777216
这个size的单位应该是byte。上边分区表是kb，因此就是第一步的大小*1024就是这个值。
3、该分区无需在AB升级中去升级，添加如下改动device/qcom/vendor-common/ota_merge_configs/dynamic_partition/non_ab：
diff --git a/ota_merge_configs/dynamic_partition/non_ab/merge_config_other_item_list b/ota_merge_configs/dynamic_partition/non_ab/merge_config_other_item_list
index d67f070..ec78e5d 100644
--- a/ota_merge_configs/dynamic_partition/non_ab/merge_config_other_item_list
+++ b/ota_merge_configs/dynamic_partition/non_ab/merge_config_other_item_list
@@ -1,5 +1,6 @@
IMAGES/cache.img
IMAGES/vendor.img
+IMAGES/jingang.img
IMAGES/vendor.map
IMAGES/odm.img
IMAGES/odm.map4、创建该分区的挂载目录system/core/rootdir：
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index a9d0ed08a..c6443fed0 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -103,6 +103,9 @@ ifdef BOARD_USES_METADATA_PARTITION
LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/metadata
endif
+# unrecovery dir
+LOCAL_POST_INSTALL_CMD += ; mkdir -p $(TARGET_ROOT_OUT)/jingang
+
# For /odm partition.
5、system/sepolicy添加上一步创建挂载目录的selinux相关定义：
diff --git a/vendor/file.te b/vendor/file.te
index 0b1fd7480..77e2ae8b2 100644
--- a/vendor/file.te
+++ b/vendor/file.te
@@ -1,2 +1,3 @@
type hostapd_data_file, file_type, data_file_type;
type wpa_data_file, file_type, data_file_type;
+type jingang_data_file, file_type;
diff --git a/vendor/file_contexts b/vendor/file_contexts
index 1b2bc2357..0d2ef214c 100644
--- a/vendor/file_contexts
+++ b/vendor/file_contexts
@@ -94,6 +94,10 @@
/(vendor|system/vendor)/lib(64)?/libhidltransport.so u:object_r:same_process_hal_file:s0
#############################
+
+# for unrecovery partition
+/jingang(/.*)? u:object_r:jingang_data_file:s0
+
# Data files
#
不添加这一步会导致编译时报system大小不够的错误，这个是这里导致的，不用调整System分区大小。
6、android/device/qcom/trinket 添加fstab自动挂载的指令并修改文件系统节点权限：
diff --git a/default/fstab_AB_dynamic_partition.qti b/default/fstab_AB_dynamic_partition.qti
index 2557d59..a1733fe 100644
--- a/default/fstab_AB_dynamic_partition.qti
+++ b/default/fstab_AB_dynamic_partition.qti
@@ -52,3 +52,4 @@ vendor /vendor
# and fails if it does not find it.
/dev/block/bootdevice/by-name/misc /misc emmc defaults defaults
/dev/block/zram0 none swap defaults zramsize=1073741824
+/dev/block/bootdevice/by-name/jingang /jingang ext4 defaults defaults
diff --git a/emmc/fstab_AB_dynamic_partition.qti b/emmc/fstab_AB_dynamic_partition.qti
index 84dd179..f1211c8 100644
--- a/emmc/fstab_AB_dynamic_partition.qti
+++ b/emmc/fstab_AB_dynamic_partition.qti
@@ -52,3 +52,4 @@ vendor /vendor
# and fails if it does not find it.
/dev/block/bootdevice/by-name/misc /misc emmc defaults defaults
/dev/block/zram0 none swap defaults zramsize=1073741824
+/dev/block/bootdevice/by-name/jingang /jingang ext4 defaults defaults
diff --git a/init.target.rc b/init.target.rc
index 89d0fa2..ca7573b 100755
--- a/init.target.rc
+++ b/init.target.rc
@@ -53,6 +53,10 @@ on fs
restorecon_recursive /mnt/vendor/persist
mkdir /mnt/vendor/persist/data 0700 system system
+ chown root root /jingang
+ chmod 0777 /jingang
+ restorecon_recursive /jingang
+
on post-fs
7、此分区涉及需要刷机的时候把image刷进去，我用的是一个空的ext4
格式的100M的image文件，也可以添加到build规则里去编译创建，我用的是命令手动创建然后cp到out目录，用来刷机。
制作命令如下：
dd if=/dev/zero of=jingang.img bs=1024 count=102400
mkfs.ext4 jingang.img
diff --git a/trinket.mk b/trinket.mk
index 9c59483..7fa8559 100644
--- a/trinket.mk
+++ b/trinket.mk
@@ -340,6 +340,7 @@ PRODUCT_PROPERTY_OVERRIDES += \
PRODUCT_PROPERTY_OVERRIDES += \
ro.boot.wificountrycode=CN
+PRODUCT_COPY_FILES += device/qcom/trinket/res/jingang.img:$(PRODUCT_OUT)/jingang.img
8、添加物理分区节点的权限device/qcom/common：
diff --git a/rootdir/etc/init.qcom.rc b/rootdir/etc/init.qcom.rc
index b2813214..5d543e2e 100755
--- a/rootdir/etc/init.qcom.rc
+++ b/rootdir/etc/init.qcom.rc
@@ -202,6 +202,10 @@ on boot
# bond0 used by FST Manager
chown wifi wifi /sys/class/net/bond0/bonding/queue_id
+ # unrecoverable sysfs node
+ chown root system /dev/block/bootdevice/by-name/jingang
+ chmod 0777 /dev/block/bootdevice/by-name/jingang
+
# Allow access to emmc rawdump block partition and dload sysfs node
chown root system /dev/block/bootdevice/by-name/rawdump
chmod 0660 /dev/block/bootdevice/by-name/rawdump9、修改刷机的内容xml，将该分区及image索引对应上：
diff --git a/contents.xml b/contents.xml
index f8ca08f..1b22391 100755
--- a/contents.xml
+++ b/contents.xml
@@ -49,6 +49,10 @@
<file_name>abl.elf</file_name>
<file_path>LINUX/android/out/target/product/trinket/</file_path>
</download_file>
+ <download_file sparse_image_path="true" minimized="true" fastboot="true">
+ <file_name>jingang.img</file_name>
+ <file_path>LINUX/android/out/target/product/trinket/</file_path>
+ </download_file>
<download_file sparse_image_path="true" minimized="true" fastboot="true">
<file_name>super.img</file_name>
<file_path>LINUX/android/out/target/product/trinket/</file_path>后边就是一系列各种selinux规则添加：
10、这是在device目录下的sepolicy改动：
diff --git a/generic/vendor/common/device.te b/generic/vendor/common/device.te
index e80846f9..6e2fa80e 100644
--- a/generic/vendor/common/device.te
+++ b/generic/vendor/common/device.te
@@ -67,3 +67,5 @@ type vendor_uefi_block_device, dev_type;
type vendor_qce_device, dev_type;
type vendor_npu_device, dev_type;
type vendor_qmcs_block_device, dev_type;
+
+type jingang_block_device,dev_type;
diff --git a/generic/vendor/common/file_contexts b/generic/vendor/common/file_contexts
index a901d15d..db0062c3 100755
--- a/generic/vendor/common/file_contexts
+++ b/generic/vendor/common/file_contexts
@@ -113,6 +113,8 @@
# Block device for ZRAM
/dev/block/zram0 u:object_r:swap_block_device:s0
+/dev/block/bootdevice/by-name/jingang u:object_r:jingang_block_device:s0
+
# files in /vendor
/vendor/firmware(/.*)? u:object_r:vendor_firmware_file:s0
/vendor/bt_firmware(/.*)? u:object_r:vendor_firmware_file:s0
diff --git a/generic/vendor/common/fsck.te b/generic/vendor/common/fsck.te
index 488eff25..150d5be3 100644
--- a/generic/vendor/common/fsck.te
+++ b/generic/vendor/common/fsck.te
@@ -29,3 +29,4 @@
allow fsck vendor_persist_block_device:blk_file rw_file_perms;
allow fsck vendor_qmcs_block_device:blk_file rw_file_perms;
allowxperm fsck vendor_qmcs_block_device:blk_file ioctl { BLKGETSIZE };
+allow fsck jingang_block_device:blk_file rw_file_perms;
diff --git a/generic/vendor/common/init.te b/generic/vendor/common/init.te
index 21268e50..b38c74ad 100644
--- a/generic/vendor/common/init.te
+++ b/generic/vendor/common/init.te
@@ -52,6 +52,10 @@ allow init vendor_qmcs_file:filesystem { relabelfrom mount unmount relabelto };
dontaudit init kernel:system module_request;
+allow init jingang_block_device:blk_file rw_file_perms;
+allow init jingang_block_device:blk_file relabelto;
+allow init jingang_data_file:dir { mounton };
+
allow init sysfs_leds:lnk_file r_file_perms;
allow init socket_device:sock_file create_file_perms;
diff --git a/generic/vendor/common/shell.te b/generic/vendor/common/shell.te
index 3c0918a8..597739ac 100644
--- a/generic/vendor/common/shell.te
+++ b/generic/vendor/common/shell.te
@@ -28,4 +28,8 @@
# allow any 3rd party shell app to be a client of DSP HAL
hal_client_domain(shell, vendor_hal_dspmanager)
-get_prop(shell, vendor_opengles_prop)
\ No newline at end of file
+get_prop(shell, vendor_opengles_prop)
+
+r_dir_file(shell, jingang_data_file)
+allow shell jingang_data_file:dir { search open read write add_name create getattr setattr };
+allow shell jingang_data_file:file { open read create write getattr setattr};
diff --git a/generic/vendor/common/vold.te b/generic/vendor/common/vold.te
index bd86659e..d8cd738c 100644
--- a/generic/vendor/common/vold.te
+++ b/generic/vendor/common/vold.te
@@ -29,3 +29,6 @@ get_prop(vold, vendor_tee_listener_prop)
# Based on the comment from b/111409607 FITRIM might
# be needed
allow vold mnt_vendor_file:dir { open read ioctl };
+allow vold jingang_data_file:dir r_dir_perms;
+allow vold jingang_block_device:blk_file { create setattr unlink rw_file_perms };
+allow vold jingang_data_file:dir { read getattr open ioctl };依次添加的为：生命device节点类型、添加到file上下文、添加开机阶段fsck的操作权限（否则挂载不上）、添加init进程访问节点权限、添加shell访问挂载目录的权限、添加vold挂载节点的权限。
12、整编源码，编译完成确认在out下是否有手动制作的image，然后用QF刷机工具先指定contents.xml打包刷机包，再用QF刷机验证。
13、系统启动后，shell进入，执行df -h可以看到分区是否挂载了；然后cd /jingang目录创建一些文件和目录，然后执行恢复出厂设置。
14、待恢复完成启动后，cd /jingang目录确认所创建的文件和目录是否还存在，若存在，则需求已实现。
15、具体的可能还需要添加systemapp或者platformapp的目录读写权限，在此不再赘述，可根据报错自行添加规则验证。
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