Use qcow2 by default for savevm, loadvm.

Create shortcuts for -t linux-reconfigure and -t host-qemu-reconfigure.

README.adoc

@@ -95,6 +95,12 @@ If you change any package besides `kernel_module`, you must also request those p
 
 Those aren't turned on by default because they take quite a few seconds.
 
+Linux and QEMU rebuilds are so common that we have dedicated shortcut flags for them:
+
+....
+./build -l -q
+....
+
 ==== Filesystem persistency
 
 The root filesystem is persistent across:

build

@@ -7,7 +7,7 @@ j="$(($(nproc) - 2))"
 post_script_args=''
 x11=false
 v=0
-while getopts 'a:j:p:St:v' OPT; do
+while getopts 'a:j:lp:qSt:v' OPT; do
   case "$OPT" in
     a)
       arch="$OPTARG"
@@ -15,9 +15,15 @@ while getopts 'a:j:p:St:v' OPT; do
     j)
       j="$OPTARG"
     ;;
+    l)
+      extra_targets="$extra_args linux-reconfigure"
+    ;;
     p)
       post_script_args="$OPTARG"
     ;;
+    q)
+      extra_targets="$extra_args host-qemu-reconfigure"
+    ;;
     S)
       qemu_sdl=''
     ;;

buildroot_config_fragment

@@ -5,6 +5,7 @@ BR2_PACKAGE_OVERRIDE_FILE="../buildroot_override"
 BR2_PACKAGE_STRACE=y
 BR2_ROOTFS_OVERLAY="../rootfs_overlay"
 BR2_ROOTFS_POST_BUILD_SCRIPT="../rootfs_post_build_script"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="../rootfs_post_image_script"
 BR2_ROOTFS_USERS_TABLES="../user_table"
 
 # Host GDB

rootfs_post_build_script

@@ -10,7 +10,6 @@ net=true
 while getopts 'n' OPT; do
   case "$OPT" in
     n)
-      echo asdfqwer
       net=false
     ;;
   esac

rootfs_post_image_script

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+images_dir="$1"
+cd "$images_dir"
+"${HOST_DIR}/bin/qemu-img" convert -f raw -O qcow2 rootfs.ext2 rootfs.ext2.qcow2

run

@@ -65,7 +65,7 @@ case "$arch" in
 -append 'root=/dev/vda nopat $extra_append' \
 -device edu \
 -device virtio-net-pci,netdev=net0 \
--drive file=${images_dir}/rootfs.ext2,if=virtio,format=raw \
+-drive file=${images_dir}/rootfs.ext2.qcow2,if=virtio,format=qcow2 \
 -kernel ${images_dir}/bzImage \
 $extra_flags \
 "
@@ -78,7 +78,7 @@ $extra_flags \
 -M versatilepb \
 -append 'root=/dev/sda $extra_append' \
 -device rtl8139,netdev=net0 \
--drive file=${images_dir}/rootfs.ext2,if=scsi,format=raw \
+-drive file=${images_dir}/rootfs.ext2.qcow2,if=scsi,format=qcow2 \
 -dtb ${images_dir}/versatile-pb.dtb \
 -kernel ${images_dir}/zImage \
 -serial stdio \