From 7b4f21e81dd037ed10ab53df3a9ceaaadb6f07e6 Mon Sep 17 00:00:00 2001
From: Konstantin Vyshetsky <vkon@google.com>
Date: Mon, 11 Oct 2021 16:34:03 -0700
Subject: [PATCH] gs201: add script to convert persist to f2fs

Currently the persist partition is formatted as ext4. In order to
convert the partition to f2fs without losing data, add a script which
will copy the partition contents out, format the partition as f2fs and
then copy the contents back.

Bug: 202511062
Signed-off-by: Konstantin Vyshetsky <vkon@google.com>
Change-Id: I89502694d1e02261902525c11ac875dd7756721b
---
 conf/init.gs201.rc |  2 ++
 convert_to_f2fs.sh | 81 ++++++++++++++++++++++++++++++++++++++++++++++
 device.mk          |  4 +++
 3 files changed, 87 insertions(+)
 create mode 100644 convert_to_f2fs.sh

diff --git a/conf/init.gs201.rc b/conf/init.gs201.rc
index d80b5bc4..3ef6a955 100644
--- a/conf/init.gs201.rc
+++ b/conf/init.gs201.rc
@@ -14,6 +14,8 @@ service vendor.charger /system/bin/charger
     file /proc/last_kmsg r
 
 on early-init
+    # Convert /dev/block/by-name/persist to f2fs
+    exec -- /vendor/bin/convert_to_f2fs.sh /dev/block/by-name/persist false
     mount_all /vendor/etc/fstab.persist --early
 
 on init
diff --git a/convert_to_f2fs.sh b/convert_to_f2fs.sh
new file mode 100644
index 00000000..806964c3
--- /dev/null
+++ b/convert_to_f2fs.sh
@@ -0,0 +1,81 @@
+#!/bin/sh
+
+BLK=$1
+FORMAT_ONLY=$2
+MNT_OLD="/mnt/convert_old"
+MNT_NEW="/mnt/convert_new"
+
+function log() {
+	if [ ! -z "$1" ]; then
+		echo "partition_convert: $1" > /dev/kmsg
+	fi
+}
+
+function check_success() {
+	if [ $? -ne 0 ]; then
+		log "Failed: $1"
+		exit -1
+	fi
+	log "Success: $1"
+}
+
+F2FS_MAGIC=$(xxd $BLK -s 0x400 -l 4 -p)
+if [ "$F2FS_MAGIC" = "1020f5f2" ]; then
+	log "$BLK is already f2fs - skipping"
+	exit 0
+fi
+
+EXT4_MAGIC=$(xxd $BLK -s 0x438 -l 2 -p)
+if [ "$EXT4_MAGIC" != "53ef" ]; then
+	log "Unknown filesystem $EXT4_MAGIC"
+	exit -1
+fi
+
+if [ $FORMAT_ONLY == "true" ]; then
+	make_f2fs $BLK 2>&1 > /dev/null
+	check_success "make_f2fs $BLK"
+	sync
+	check_success "sync"
+	exit 0
+fi
+
+mkdir -p $MNT_OLD
+check_success "mkdir $MNT_OLD"
+
+mkdir -p $MNT_NEW
+check_success "mkdir $MNT_NEW"
+
+mount -t ext4 $BLK $MNT_OLD
+check_success "mount $MNT_OLD as ext4"
+
+mount -t tmpfs tmpfs $MNT_NEW
+check_success "mount $MNT_NEW as tmpfs"
+
+cp -rp $MNT_OLD/* $MNT_NEW/
+check_success "copy $MNT_OLD to $MNT_NEW"
+
+umount $MNT_OLD
+check_success "umount $MNT_OLD"
+
+make_f2fs $BLK 2>&1 > /dev/null
+check_success "make_f2fs $BLK"
+
+mount -t f2fs $BLK $MNT_OLD
+check_success "mount $MNT_OLD as f2fs"
+
+cp -rp $MNT_NEW/* $MNT_OLD/
+check_success "copy $MNT_NEW to $MNT_OLD"
+
+sync
+check_success "sync"
+
+umount $MNT_OLD
+check_success "umount $MNT_OLD"
+umount $MNT_NEW
+check_success "umount $MNT_NEW"
+
+rmdir $MNT_OLD
+check_success "rmdir $MNT_OLD"
+
+rmdir $MNT_NEW
+check_success "rmdir $MNT_NEW"
diff --git a/device.mk b/device.mk
index 8a61dda2..91aec963 100644
--- a/device.mk
+++ b/device.mk
@@ -286,6 +286,10 @@ PRODUCT_PACKAGES += \
 	tune2fs.vendor_ramdisk \
 	resize2fs.vendor_ramdisk
 
+# Filesystem: convert /dev/block/by-name/persist to f2fs
+PRODUCT_COPY_FILES += \
+	device/google/gs201/convert_to_f2fs.sh:$(TARGET_COPY_OUT_VENDOR)/bin/convert_to_f2fs.sh \
+
 # Userdata Checkpointing OTA GC
 PRODUCT_PACKAGES += \
 	checkpoint_gc