Kata initrd的生成过程

可参考kata_integration中make initrd流程，大致分为以下几步：

  1. 创建rootfs相关目录
  2. 将kata-agent重命名为init并放在rootfs根目录下
  3. 从编译环境中拷贝kata-agent所需二进制（如mount、umount）到rootfs usr/bin目录下
  4. 从编译环境中拷贝以上二进制（包含kata-agent）所需动态链接库到rootfs lib目录下
  5. 从编译环境中拷贝内核驱动模块ko文件到rootfs中内核驱动模块目录下
  6. 进入rootfs并执行以下命令生成initrd.img
  1. ( find . | cpio -H newc -o | gzip -9 ) > ./kata-containers-initrd.img

initrd定制参考脚本

  1. script_dir="$(dirname $(readlink -f $0))"
  2. rpmlist=${script_dir}/make-initrd-rpm.list
  4. BUILD_PATH="./build"
  5. IMAGE_NAME=${IMAGE_NAME:-kata-containers-initrd.img}
  6. AGENT_INIT=${AGENT_INIT:-yes}
  7. ROOTFS_DIR=${ROOTFS_DIR:-/tmp/kataAgent-rootfs}
  9. # create a temp dir to store rootfs
  10. rm -rf ${ROOTFS_DIR}
  11. mkdir -p ${ROOTFS_DIR}/lib \
  12.       ${ROOTFS_DIR}/lib64 \
  13.       ${ROOTFS_DIR}/lib/modules
  15. mkdir -m 0755 -p ${ROOTFS_DIR}/dev \
  16.       ${ROOTFS_DIR}/sys \
  17.       ${ROOTFS_DIR}/sbin \
  18.       ${ROOTFS_DIR}/bin \
  19.       ${ROOTFS_DIR}/tmp \
  20.       ${ROOTFS_DIR}/proc
  22. if [ ! -f "${BUILD_PATH}/kata-agent" ];then
  23.     echo "kata-agent doesn't exist!"
  24.     exit 1
  25. fi
  27. # kata-agent
  28. cp ${BUILD_PATH}/kata-agent ${ROOTFS_DIR}/init
  30. # busybox
  31. cp /sbin/busybox ${ROOTFS_DIR}/sbin/
  33. # cp run request files in initrd
  34. cat $rpmlist | while read rpm
  35. do
  36.     if [ "${rpm:0:1}" != "#" ]; then
  37.         rpm -ql $rpm > /dev/null 2>&1
  38.         if [ $? -ne 0 ]; then
  39.             continue
  40.         fi
  41.         array=($(rpm -ql $rpm| grep -v "share" | grep -v ".build-id"))
  42.         for file in ${array[@]};
  43.         do
  44.             source=$file
  45.             dts_file=${ROOTFS_DIR}$file
  46.             dts_folder=${dts_file%/*}
  47.             if [ ! -d "$dts_folder" ];then
  48.                 mkdir -p $dts_folder
  49.             fi
  50.             cp -r -f -d $source $dts_folder
  51.         done
  52.     fi
  53. done
  55. #create symlinks to busybox
  56. BUSYBOX_BINARIES=(/bin/sh /bin/mount /bin/umount /bin/ls /bin/ps /bin/file /bin/ldd /bin/tar /bin/hwclock /sbin/modprobe /sbin/depmod /bin/ip /bin/modinfo /bin/insmod /bin/rmmod)
  57. for bin in ${BUSYBOX_BINARIES[@]}
  58. do
  59.      mkdir -p ${ROOTFS_DIR}/`dirname ${bin}`
  60.      ln -sf /sbin/busybox ${ROOTFS_DIR}/${bin}
  61. done
  63. LDD_BINARIES=(/init /sbin/busybox)
  64. for bin in ${LDD_BINARIES[@]}
  65.  do
  66.      ldd ${ROOTFS_DIR}${bin} | while read line
  67.      do
  68.          arr=(${line// / })
  70.          for lib in ${arr[@]}
  71.          do
  72.              echo $lib
  73.              if [ "${lib:0:1}" = "/" ]; then
  74.                  dir=${ROOTFS_DIR}`dirname $lib`
  75.                  mkdir -p "${dir}"
  76.                  cp -f $lib $dir
  77.              fi
  78.          done
  79.      done
  80.  done
  82. (cd ${ROOTFS_DIR} && find . | cpio -H newc -o | gzip -9 ) > ${BUILD_PATH}/${IMAGE_NAME}