From: Jacek Kryszyn <j.kryszyn@samsung.com>
Date: Wed, 3 Apr 2024 14:16:11 +0000 (+0200)
Subject: Clone partitions using head instead of dd
X-Git-Tag: accepted/tizen/unified/20240430.020633~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=826b0c40b3efb37a3c51d3a1fa2f80eecdb5dc23;p=platform%2Fcore%2Fsystem%2Fupgrade.git

Clone partitions using head instead of dd

Instead of cloning partitions (whole disks) using dd,
head -c $part_size is used to copy only necessary bytes.
This can be much faster in case of partitions placed
on much bigger disks.

Change-Id: Ie15b9f543bac8ef351ef0a4ed4e9adfd148cf704
---

diff --git a/scripts/upgrade-support/upgrade-common.inc b/scripts/upgrade-support/upgrade-common.inc
index d542590..e53ab46 100644
--- a/scripts/upgrade-support/upgrade-common.inc
+++ b/scripts/upgrade-support/upgrade-common.inc
@@ -235,6 +235,33 @@ check_used_block_device() {
 	check_if_super
 }
 
+calculate_size () {
+	local part=$1
+	local info=""
+	local block_size=0
+	local block_count=0
+	local size=0
+
+	untrap
+
+	if info="$(dumpe2fs -h "$part" 2>/dev/null)"; then
+		retrap
+		block_size="$(echo "$info" | grep "Block size" | awk '{print $3}')"
+		block_count="$(echo "$info" | grep "Block count" | awk '{print $3}')"
+		echo "$((block_size*block_count))"
+		return 0
+	fi
+
+	if size="$(blockdev --getsize64 "$part" 2>/dev/null)"; then
+		retrap
+		echo "$size"
+		return 0
+	fi
+
+	retrap
+	return 1
+}
+
 background_copy() {
 	log "[Info] Background copying A|B partitions for update..."
 	start_duration=$(date +%s)
@@ -295,7 +322,8 @@ background_copy() {
 				fi
 			fi
 		else
-			/bin/dd if="$CURRENT_PARTITION" of="$NEXT_PARTITION" bs=4096
+			PART_SIZE="$(calculate_size "$CURRENT_PARTITION")"
+			head -c "$PART_SIZE" "$CURRENT_PARTITION" > "$NEXT_PARTITION"
 		fi
 		log "[Info] Finished background copy $partition_name from $CURRENT_PARTITION to $NEXT_PARTITION"
 
@@ -310,8 +338,8 @@ background_copy() {
 					NEXT_SHA1=$(head -c "$ROOTFS_CURR_SIZE" "$NEXT_PARTITION" | sha1sum | awk '{print $1}')
 				fi
 			else
-				CUR_SHA1=$(sha1sum "$CURRENT_PARTITION" | awk '{print $1}')
-				NEXT_SHA1=$(sha1sum "$NEXT_PARTITION" | awk '{print $1}')
+				CUR_SHA1=$(head -c "$PART_SIZE" "$CURRENT_PARTITION" | sha1sum | awk '{print $1}')
+				NEXT_SHA1=$(head -c "$PART_SIZE" "$NEXT_PARTITION" | sha1sum | awk '{print $1}')
 			fi
 
 			if [ "$CUR_SHA1" == "$NEXT_SHA1" ]; then