Re: [PATCH 2/3] wic: apply the actual fork changes to our pcbios plugin fork

[Henning Schild <henning.schild@siemens.com>]

Am Fri, 27 Aug 2021 09:35:24 +0200
schrieb "Bezdeka, Florian (T RDA IOT SES-DE)"
<florian.bezdeka@siemens.com>:

> On Thu, 2021-08-26 at 21:28 +0200, Henning Schild wrote:
> > This aims to be a rather minimal one-commit fork to do isar specific
> > changes to the forked class. It does things in a way that results in
> > somehow strange code but pretty clean patching that aims to be easy
> > to read and mostly about adding lines to get things done. The hope
> > is that it will make maintaining the fork easier than before.
> >
> > Signed-off-by: Henning Schild <henning.schild@siemens.com>
> > ---
> >  .../wic/plugins/source/bootimg-pcbios-isar.py | 36
> > +++++++++++++++++-- 1 file changed, 33 insertions(+), 3 deletions(-)
> >
> > diff --git
> > a/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
> > b/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py index
> > f2639e700493..3a3a6f09392f 100644 ---
> > a/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py +++
> > b/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py @@
> > -4,7 +4,7 @@ # SPDX-License-Identifier: GPL-2.0-only #
> >  # DESCRIPTION
> > -# This implements the 'bootimg-pcbios' source plugin class for
> > 'wic' +# This implements the 'bootimg-pcbios-isar' source plugin
> > class for 'wic' #
> >  # AUTHORS
> >  # Tom Zanussi <tom.zanussi (at] linux.intel.com>
> > @@ -22,12 +22,12 @@ from wic.misc import (exec_cmd, exec_native_cmd,
> >
> >  logger = logging.getLogger('wic')
> >
> > -class BootimgPcbiosPlugin(SourcePlugin):
> > +class BootimgPcbiosIsarPlugin(SourcePlugin):
> >      """
> >      Create MBR boot partition and install syslinux on it.
> >      """
> >
> > -    name = 'bootimg-pcbios'
> > +    name = 'bootimg-pcbios-isar'
> >
> >      @classmethod
> >      def _get_bootimg_dir(cls, bootimg_dir, dirname):
> > @@ -56,6 +56,10 @@ class BootimgPcbiosPlugin(SourcePlugin):
> >          """
> >          bootimg_dir = cls._get_bootimg_dir(bootimg_dir, 'syslinux')
> >          mbrfile = "%s/syslinux/" % bootimg_dir
> > +
> > +        # files have different prefix in debian
> > +        mbrfile += "mbr/"
> > +
> >          if creator.ptable_format == 'msdos':
> >              mbrfile += "mbr.bin"
> >          elif creator.ptable_format == 'gpt':
> > @@ -123,11 +127,27 @@ class BootimgPcbiosPlugin(SourcePlugin):
> >              syslinux_conf += "LABEL boot\n"
> >
> >              kernel = "/vmlinuz"
> > +
> > +            # figure out the real filename in /boot/ by following
> > debian symlinks
> > +            kernel_file = get_bitbake_var("KERNEL_FILE")
> > +            rootfs_dir = get_bitbake_var("IMAGE_ROOTFS")
> > +            kernel =
> > os.path.basename(os.path.realpath(os.path.join(rootfs_dir,
> > kernel_file))) + syslinux_conf += "KERNEL " + kernel + "\n"
> >
> >              syslinux_conf += "APPEND label=boot root=%s %s\n" % \
> >                               (creator.rootdev, bootloader.append)
> >
> > +            # we are using an initrd, smuggle it in
> > +            initrd = "initrd.img"
> > +            kernel_parts = kernel.split("-")
> > +            kernel_suffix = "-".join(kernel_parts[1:])
> > +            if kernel_suffix:
> > +                initrd += "-%s" % kernel_suffix  
> 
> I guess I was the last one modifying this file... Just had a look at
> upstream commit d3f1af4e2318a4420f4c7f23edd093f66891ca8b, which seems
> partially reverted now.
> 
> I'm missing the part in do_prepare_partition, where the kernel_suffix
> should be optional as well. Maybe I'm just missing / overlooking
> something?

There used to be two places where the actual filename of the kernel was
found following the symlink in /. The suffix was extracted to figure
out the name of the initrd. The places have been "copy" and "configure".

In addition "copy" dealt with config and System.map. I changed "copy"
to be "cp -a" simply copying everything from /boot into the boot
partition which will later be mounted at /boot. Meaning no need to know
the filename follow symlinks, derive initrd and other filenames via
"guessing".

So that "cp -a" does take care of the bits that i "reverted". It also
deals with the additional files (config, System.map) introduces by
328dc021ec3d8a1eaff72324b3e9646a0fd5e128 from Vijai.

> > +
> > +            syslinux_conf = syslinux_conf.replace(" root=%s " %
> > (creator.rootdev),
> > +                                                  " root=%s
> > initrd=%s " % (creator.rootdev, initrd)) +
> >          logger.debug("Writing syslinux config
> > %s/hdd/boot/syslinux.cfg", cr_workdir)
> >          cfg = open("%s/hdd/boot/syslinux.cfg" % cr_workdir, "w")
> > @@ -166,7 +186,17 @@ class BootimgPcbiosPlugin(SourcePlugin):
> >                  "install -m 444 %s/syslinux/libutil.c32
> > %s/libutil.c32" % (bootimg_dir, hdddir))
> >
> > +        # install /boot from our debian rootfs completely
> > +        cmds = cmds + ("cp -a %s/%s %s/.." %
> > (rootfs_dir['ROOTFS_DIR'], "boot", hdddir),) +

This is the "magic" line. Copying all files from debian so the plugin
does not need to know there names and name them all.

Henning

> >          for install_cmd in cmds:
> > +            # skip the kernel install from OE parts, "cp -a" will
> > bring our kernel
> > +            if install_cmd == cmds[0]:
> > +                continue
> > +            # one file has a different suffix in debian
> > +            install_cmd = install_cmd.replace("ldlinux.sys",
> > "ldlinux.c32")
> > +            # files have different prefix in debian
> > +            install_cmd = install_cmd.replace("/syslinux/",
> > "/syslinux/modules/bios/") exec_cmd(install_cmd)
> >
> >          du_cmd = "du -bks %s" % hdddir
> > --
> > 2.31.1
> >  
>