From f46269aba8a0bc2b60a0305bdafd8dfb42e0bb88 Mon Sep 17 00:00:00 2001
From: Colin Percival <cperciva@FreeBSD.org>
Date: Wed, 7 Oct 2026 17:52:01 -0700
Subject: [PATCH] vmimage.subr: Support partition alignment

If VM_PARTALIGN is set, pass %${VM_PARTALIGN} to mkimg in the
specification of swap, config, root, and ESP partitions.  (Boot
partitions are not aligned, both because they're small and in
case firmware makes assumptions about their locations.)

Reviewed by:	lwhsu, imp
MFC after:	1 week
Sponsored by:	Amazon
Differential Revision:	https://reviews.freebsd.org/D60454
---
 release/tools/vmimage.subr | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/release/tools/vmimage.subr b/release/tools/vmimage.subr
index b8d2be965dde..e7e7b9607b15 100644
--- a/release/tools/vmimage.subr
+++ b/release/tools/vmimage.subr
@@ -369,10 +369,14 @@ umount_loop() {
 }
 
 vm_create_disk() {
-	local BOOTFILES BOOTPARTSOFFSET FSPARTTYPE X86GPTBOOTFILE
+	local BOOTFILES BOOTPARTSOFFSET FSPARTTYPE PARTALIGN X86GPTBOOTFILE
+
+	if [ -n "${VM_PARTALIGN}" ]; then
+		PARTALIGN="%${VM_PARTALIGN}"
+	fi
 
 	if [ -z "${NOSWAP}" ]; then
-		SWAPOPT="-p freebsd-swap/swapfs::${SWAPSIZE}"
+		SWAPOPT="-p freebsd-swap/swapfs::${SWAPSIZE}${PARTALIGN}"
 	fi
 
 	if [ -n "${VM_BOOTPARTSOFFSET}" ]; then
@@ -380,7 +384,7 @@ vm_create_disk() {
 	fi
 
 	if [ -n "${CONFIG_DRIVE}" ]; then
-		CONFIG_DRIVE="-p freebsd/config-drive::${CONFIG_DRIVE_SIZE}"
+		CONFIG_DRIVE="-p freebsd/config-drive::${CONFIG_DRIVE_SIZE}${PARTALIGN}"
 	fi
 
 	case "${VMFS}" in
@@ -412,19 +416,19 @@ vm_create_disk() {
 			ESP=yes
 			BOOTPARTS="-b ${BOOTFILES}/i386/pmbr/pmbr \
 				   -p freebsd-boot/bootfs:=${BOOTFILES}/${X86GPTBOOTFILE}${BOOTPARTSOFFSET}"
-			ROOTFSPART="-p ${FSPARTTYPE}/rootfs:=${VMBASE}"
+			ROOTFSPART="-p ${FSPARTTYPE}/rootfs:=${VMBASE}${PARTALIGN}"
 			MAKEFSARGS="$MAKEFSARGS -B little"
 			;;
 		arm:armv7 | arm64:aarch64 | riscv:riscv64*)
 			ESP=yes
 			BOOTPARTS=
-			ROOTFSPART="-p ${FSPARTTYPE}/rootfs:=${VMBASE}"
+			ROOTFSPART="-p ${FSPARTTYPE}/rootfs:=${VMBASE}${PARTALIGN}"
 			MAKEFSARGS="$MAKEFSARGS -B little"
 			;;
 		powerpc:powerpc*)
 			ESP=no
 			BOOTPARTS="-p prepboot:=${BOOTFILES}/powerpc/boot1.chrp/boot1.elf -a 1"
-			ROOTFSPART="-p freebsd:=${VMBASE}"
+			ROOTFSPART="-p freebsd:=${VMBASE}${PARTALIGN}"
 			if [ ${TARGET_ARCH} = powerpc64le ]; then
 				MAKEFSARGS="$MAKEFSARGS -B little"
 			else
@@ -445,7 +449,7 @@ vm_create_disk() {
 		if [ -z "${BOOTPARTS}" ]; then
 			espsuffix="${BOOTPARTSOFFSET}"
 		fi
-		BOOTPARTS="${BOOTPARTS} -p efi/efiboot0:=${espfilename}${espsuffix}"
+		BOOTPARTS="${BOOTPARTS} -p efi/efiboot0:=${espfilename}${espsuffix}${PARTALIGN}"
 
 		# Add this to fstab
 		mkdir -p ${DESTDIR}/boot/efi