Re: [PATCH v2 12/17] wic: Add pcibios boot plugins and wks files

[Andreas Reichel <andreas.reichel.ext@siemens.com>]

On Fri, Apr 13, 2018 at 04:19:01PM +0200, Henning Schild wrote:
> Create a modified version of directdisk.wks that enabled legacy boot
> images in Isar. "bootimg-pcbios-isar" expects the buildchroot to contain
> the packages "syslinux syslinux-common" and will create a disk using this
> bootloader.
> 
> Signed-off-by: Henning Schild <henning.schild@siemens.com>
> ---
>  .../scripts/lib/wic/canned-wks/common-isar.wks.inc |   3 +
>  .../scripts/lib/wic/canned-wks/directdisk-isar.wks |   7 +
>  .../lib/wic/plugins/source/bootimg-pcbios-isar.py  | 217 +++++++++++++++++++++
>  3 files changed, 227 insertions(+)
>  create mode 100644 meta-isar/scripts/lib/wic/canned-wks/common-isar.wks.inc
>  create mode 100644 meta-isar/scripts/lib/wic/canned-wks/directdisk-isar.wks
>  create mode 100644 meta-isar/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
> 
> diff --git a/meta-isar/scripts/lib/wic/canned-wks/common-isar.wks.inc b/meta-isar/scripts/lib/wic/canned-wks/common-isar.wks.inc
> new file mode 100644
> index 0000000..c8ea4c2
> --- /dev/null
> +++ b/meta-isar/scripts/lib/wic/canned-wks/common-isar.wks.inc
> @@ -0,0 +1,3 @@
> +# This file is included into 3 canned wks files from this directory
> +part /boot --source bootimg-pcbios-isar --ondisk sda --label boot --active --align 1024
> +part / --source rootfs --ondisk sda --fstype=ext4 --label platform --align 1024
> diff --git a/meta-isar/scripts/lib/wic/canned-wks/directdisk-isar.wks b/meta-isar/scripts/lib/wic/canned-wks/directdisk-isar.wks
> new file mode 100644
> index 0000000..2b9576d
> --- /dev/null
> +++ b/meta-isar/scripts/lib/wic/canned-wks/directdisk-isar.wks
> @@ -0,0 +1,7 @@
> +# short-description: Create a 'pcbios' direct disk image
> +# long-description: Creates a partitioned legacy BIOS disk image that the user
> +# can directly dd to boot media.
> +
> +include common-isar.wks.inc
> +
> +bootloader  --timeout=0  --append="rootwait rootfstype=ext4 video=vesafb vga=0x318 console=tty0 console=ttyS0,115200n8"
> diff --git a/meta-isar/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py b/meta-isar/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
> new file mode 100644
> index 0000000..0423862
> --- /dev/null
> +++ b/meta-isar/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
> @@ -0,0 +1,217 @@
> +# ex:ts=4:sw=4:sts=4:et
> +# -*- tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*-
> +#
> +# Copyright (c) 2014, Intel Corporation.
> +# All rights reserved.
> +#
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License version 2 as
> +# published by the Free Software Foundation.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License along
> +# with this program; if not, write to the Free Software Foundation, Inc.,
> +# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> +#
> +# DESCRIPTION
> +# This implements the 'bootimg-pcbios-isar' source plugin class for 'wic'
> +#
> +# AUTHORS
> +# Tom Zanussi <tom.zanussi (at] linux.intel.com>
> +#
> +
> +import logging
> +import os
> +
> +from wic import WicError
> +from wic.engine import get_custom_config
> +from wic.utils import runner
> +from wic.pluginbase import SourcePlugin
> +from wic.utils.misc import (exec_cmd, exec_native_cmd,
> +                            get_bitbake_var, BOOTDD_EXTRA_SPACE)
> +
> +logger = logging.getLogger('wic')
> +
> +class BootimgPcbiosIsarPlugin(SourcePlugin):
> +    """
> +    Create MBR boot partition and install syslinux on it.
> +    """
> +
> +    name = 'bootimg-pcbios-isar'
> +
> +    @classmethod
> +    def _get_syslinux_dir(cls, bootimg_dir):
> +        """
> +        Get path to syslinux from either default bootimg_dir
> +        or wic-tools STAGING_DIR.
> +        """
> +        for path in (bootimg_dir, get_bitbake_var("STAGING_DATADIR", "wic-tools")):
> +            if not path:
> +                continue
> +            syslinux_dir = os.path.join(path, 'syslinux')
> +            if os.path.exists(syslinux_dir):
> +                return syslinux_dir
> +
> +        raise WicError("Couldn't find syslinux directory, exiting")
> +
> +    @classmethod
> +    def do_install_disk(cls, disk, disk_name, creator, workdir, oe_builddir,
> +                        bootimg_dir, kernel_dir, native_sysroot):
> +        """
> +        Called after all partitions have been prepared and assembled into a
> +        disk image.  In this case, we install the MBR.
> +        """
> +        syslinux_dir = cls._get_syslinux_dir(bootimg_dir)
> +        if creator.ptable_format == 'msdos':
> +            mbrfile = os.path.join(syslinux_dir, "mbr/mbr.bin")
> +        elif creator.ptable_format == 'gpt':
> +            mbrfile = os.path.join(syslinux_dir, "mbr/gptmbr.bin")
I know that a GPT contains an MBR for compatibility reasons. But this is
usually just to stop the system from booting of the harddisk partitioned
by GPT if it is used in an older PC accidentally. Why would one want to
install syslinux with MBR support into the protected MBR of a GPT that
should not be used for booting? Or do I get that wrong?

> +        else:
> +            raise WicError("Unsupported partition table: %s" %
> +                           creator.ptable_format)
> +
> +        if not os.path.exists(mbrfile):
> +            raise WicError("Couldn't find %s.  If using the -e option, do you "
> +                           "have the right MACHINE set in local.conf?  If not, "
> +                           "is the bootimg_dir path correct?" % mbrfile)
> +
> +        full_path = creator._full_path(workdir, disk_name, "direct")
> +        logger.debug("Installing MBR on disk %s as %s with size %s bytes",
> +                     disk_name, full_path, disk.min_size)
> +
> +        rcode = runner.show(['dd', 'if=%s' % mbrfile,
> +                             'of=%s' % full_path, 'conv=notrunc'])
> +        if rcode != 0:
> +            raise WicError("Unable to set MBR to %s" % full_path)
> +
> +    @classmethod
> +    def do_configure_partition(cls, part, source_params, creator, cr_workdir,
> +                               oe_builddir, bootimg_dir, kernel_dir,
> +                               native_sysroot):
> +        """
> +        Called before do_prepare_partition(), creates syslinux config
> +        """
> +        hdddir = "%s/hdd/boot" % cr_workdir
> +
> +        install_cmd = "install -d %s" % hdddir
> +        exec_cmd(install_cmd)
> +
> +        bootloader = creator.ks.bootloader
> +
> +        custom_cfg = None
> +        if bootloader.configfile:
> +            custom_cfg = get_custom_config(bootloader.configfile)
> +            if custom_cfg:
> +                # Use a custom configuration for grub
> +                syslinux_conf = custom_cfg
> +                logger.debug("Using custom configuration file %s "
> +                             "for syslinux.cfg", bootloader.configfile)
> +            else:
> +                raise WicError("configfile is specified but failed to "
> +                               "get it from %s." % bootloader.configfile)
> +
> +        if not custom_cfg:
> +            # Create syslinux configuration using parameters from wks file
> +            splash = os.path.join(cr_workdir, "/hdd/boot/splash.jpg")
> +            if os.path.exists(splash):
> +                splashline = "menu background splash.jpg"
> +            else:
> +                splashline = ""
> +
> +            syslinux_conf = ""
> +            syslinux_conf += "PROMPT 0\n"
> +            syslinux_conf += "TIMEOUT " + str(bootloader.timeout) + "\n"
> +            syslinux_conf += "\n"
> +            syslinux_conf += "ALLOWOPTIONS 1\n"
> +            syslinux_conf += "SERIAL 0 115200\n"
> +            syslinux_conf += "\n"
> +            if splashline:
> +                syslinux_conf += "%s\n" % splashline
> +            syslinux_conf += "DEFAULT boot\n"
> +            syslinux_conf += "LABEL boot\n"
> +
> +            kernel = get_bitbake_var("KERNEL_IMAGE")
> +            initrd = get_bitbake_var("INITRD_IMAGE")
> +            syslinux_conf += "KERNEL " + kernel + "\n"
> +
> +            syslinux_conf += "APPEND label=boot root=%s initrd=%s %s\n" % \
> +                             (creator.rootdev, initrd, bootloader.append)
> +
> +        logger.debug("Writing syslinux config %s/hdd/boot/syslinux.cfg",
> +                     cr_workdir)
> +        cfg = open("%s/hdd/boot/syslinux.cfg" % cr_workdir, "w")
> +        cfg.write(syslinux_conf)
> +        cfg.close()
> +
> +    @classmethod
> +    def do_prepare_partition(cls, part, source_params, creator, cr_workdir,
> +                             oe_builddir, bootimg_dir, kernel_dir,
> +                             rootfs_dir, native_sysroot):
> +        """
> +        Called to do the actual content population for a partition i.e. it
> +        'prepares' the partition to be incorporated into the image.
> +        In this case, prepare content for legacy bios boot partition.
> +        """
> +        syslinux_dir = cls._get_syslinux_dir(bootimg_dir)
> +
> +        staging_kernel_dir = kernel_dir
> +        kernel = get_bitbake_var("KERNEL_IMAGE")
> +        initrd = get_bitbake_var("INITRD_IMAGE")
> +
> +        hdddir = "%s/hdd/boot" % cr_workdir
> +
> +        cmds = ("install -m 0644 %s/%s %s/%s" %
> +                (staging_kernel_dir, kernel, hdddir, kernel),
> +                "install -m 0644 %s/%s %s/%s" %
> +                (staging_kernel_dir, initrd, hdddir, initrd),
> +                "install -m 444 %s/modules/bios/ldlinux.c32 %s/ldlinux.c32" %
> +                (syslinux_dir, hdddir),
> +                "install -m 0644 %s/modules/bios/vesamenu.c32 %s/vesamenu.c32" %
> +                (syslinux_dir, hdddir),
> +                "install -m 444 %s/modules/bios/libcom32.c32 %s/libcom32.c32" %
> +                (syslinux_dir, hdddir),
> +                "install -m 444 %s/modules/bios/libutil.c32 %s/libutil.c32" %
> +                (syslinux_dir, hdddir))
> +
> +        for install_cmd in cmds:
> +            exec_cmd(install_cmd)
> +
> +        du_cmd = "du -bks %s" % hdddir
> +        out = exec_cmd(du_cmd)
> +        blocks = int(out.split()[0])
> +
> +        extra_blocks = part.get_extra_block_count(blocks)
> +
> +        if extra_blocks < BOOTDD_EXTRA_SPACE:
> +            extra_blocks = BOOTDD_EXTRA_SPACE
> +
> +        blocks += extra_blocks
> +
> +        logger.debug("Added %d extra blocks to %s to get to %d total blocks",
> +                     extra_blocks, part.mountpoint, blocks)
> +
> +        # dosfs image, created by mkdosfs
> +        bootimg = "%s/boot.img" % cr_workdir
> +
> +        dosfs_cmd = "mkdosfs -n boot -S 512 -C %s %d" % (bootimg, blocks)
> +        exec_native_cmd(dosfs_cmd, native_sysroot)
> +
> +        mcopy_cmd = "mcopy -i %s -s %s/* ::/" % (bootimg, hdddir)
> +        exec_cmd(mcopy_cmd, native_sysroot)
> +
> +        syslinux_cmd = "syslinux %s" % bootimg
> +        exec_native_cmd(syslinux_cmd, native_sysroot)
> +
> +        chmod_cmd = "chmod 644 %s" % bootimg
> +        exec_cmd(chmod_cmd)
> +
> +        du_cmd = "du -Lbks %s" % bootimg
> +        out = exec_cmd(du_cmd)
> +        bootimg_size = out.split()[0]
> +
> +        part.size = int(bootimg_size)
> +        part.source_file = bootimg
> -- 
> 2.16.1
> 

-- 
Andreas Reichel
Dipl.-Phys. (Univ.)
Software Consultant

Andreas.Reichel@tngtech.com, +49-174-3180074
TNG Technology Consulting GmbH, Betastr. 13a, 85774 Unterfoehring
Geschaeftsfuehrer: Henrik Klagges, Dr. Robert Dahlke, Gerhard Mueller
Sitz: Unterfoehring * Amtsgericht Muenchen * HRB 135082