[OE-core] [PATCH 2/2] wic: Add --embed-rootfs argument
Ricardo Ribalda Delgado
ricardo at ribalda.com
Wed Mar 4 10:14:43 UTC 2020
Hi Paul
On Wed, Mar 4, 2020 at 11:09 AM Paul Barker <pbarker at konsulko.com> wrote:
>
> On Wed, 4 Mar 2020 10:56:20 +0100
> Ricardo Ribalda Delgado <ricardo at ribalda.com> wrote:
>
> > Hi Paul
> >
> > Thanks for your reply
> >
> > On Wed, Mar 4, 2020 at 10:43 AM Paul Barker <pbarker at konsulko.com> wrote:
> > >
> > > On Wed, 4 Mar 2020 09:34:38 +0100
> > > Ricardo Ribalda Delgado <ricardo at ribalda.com> wrote:
> > >
> > > > This option adds the content of a rootfs on a specific location on the
> > > > rootfs.
> > > >
> > > > It is very useful for making a partition that contains the rootfs for a
> > > > host and a target Eg:
> > > >
> > > > / -> Roofs for the host
> > > > /export/ -> Rootfs for the target (which will netboot)
> > > >
> > > > Although today we support making a partition for "/export" this might
> > > > not be compatible with some upgrade systems, or we might be limited by
> > > > the number of partitions.
> > > >
> > > > With this patch we can use something like:
> > > >
> > > > part / --source rootfs --embed-rootfs=target-image:/export
> > >
> > > I considered using a syntax like this for --include-path but I chose not to
> > > as it's not easy to choose a separator. ':' is a valid character in a
> > > directory name.
> >
> > I think we have to live with not being able to copy files to a
> > directory with a colon :(
>
> I wouldn't like to place a limitation like that on users and I'd like to
> avoid the proliferation of similar arguments here.
>
> How about modifying '--include-path' to take two arguments, a source path and
> a destination prefix? The python argument parser should be able to handle
> this and you can build a list of tuples (source_path, dest_prefix) when
> parsing the arguments.
>
> The '--include-path' argument hasn't been part of a Yocto release yet it's
> just on the master branch so I think if we're going to fix it with a breaking
> change, now is definitely the time.
That sounds good to me. I do not mind having two arguments. for
embed-rootfs. and probably will look better on include-path
>
> >
> > >
> > > My approach is to handle this in two steps:
> > >
> > > 1) Add a new task before do_image_wic which creates an 'embedded-rootfs'
> > > directory and copies 'target-image' to 'embedded-rootfs/export'.
> > >
> > > 2) Use '--include-path=embedded-rootfs' in the wks file.
> > >
> >
> > The biggest problem with that approach is permissions. We need files
> > with UID 0, siticky bits, etc. We lose the pseudo database if we
> > simply copy to a folder.
> >
> > Also, if we have a complex system with multiple partitions I prefer to
> > handle all in a single .wks file instead of a script + wks file
> >
> > > >
> > > > on the .wks file.
> > > >
> > > > Signed-off-by: Ricardo Ribalda Delgado <ricardo at ribalda.com>
> > > > ---
> > > > scripts/lib/wic/help.py | 7 +++++++
> > > > scripts/lib/wic/ksparser.py | 1 +
> > > > scripts/lib/wic/partition.py | 1 +
> > > > scripts/lib/wic/plugins/source/rootfs.py | 20 +++++++++++++++++++-
> > > > 4 files changed, 28 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/scripts/lib/wic/help.py b/scripts/lib/wic/help.py
> > > > index 4d342fcf05..67a33e6a65 100644
> > > > --- a/scripts/lib/wic/help.py
> > > > +++ b/scripts/lib/wic/help.py
> > > > @@ -979,6 +979,13 @@ DESCRIPTION
> > > > copies. This option only has an effect with the rootfs
> > > > source plugin.
> > > >
> > > > + --embed-rootfs: This option is specific to wic. It embeds a rootfs into
> > > > + the given path to the resulting image. The option
> > > > + contains two fields, the roofs and the path, separated
> > > > + by a colon. The rootfs follows the same logic as the
> > > > + rootfs-dir argument. This option only has an effect
> > > > + with the rootfs source plugin.
> > > > +
> > > > --extra-space: This option is specific to wic. It adds extra
> > > > space after the space filled by the content
> > > > of the partition. The final size can go
> > > > diff --git a/scripts/lib/wic/ksparser.py b/scripts/lib/wic/ksparser.py
> > > > index 650b976223..d422e2a6bb 100644
> > > > --- a/scripts/lib/wic/ksparser.py
> > > > +++ b/scripts/lib/wic/ksparser.py
> > > > @@ -138,6 +138,7 @@ class KickStart():
> > > > part.add_argument('--align', type=int)
> > > > part.add_argument('--exclude-path', nargs='+')
> > > > part.add_argument('--include-path', nargs='+')
> > > > + part.add_argument('--embed-rootfs', nargs='+')
> > > > part.add_argument("--extra-space", type=sizetype)
> > > > part.add_argument('--fsoptions', dest='fsopts')
> > > > part.add_argument('--fstype', default='vfat',
> > > > diff --git a/scripts/lib/wic/partition.py b/scripts/lib/wic/partition.py
> > > > index 2d95f78439..13857df82f 100644
> > > > --- a/scripts/lib/wic/partition.py
> > > > +++ b/scripts/lib/wic/partition.py
> > > > @@ -31,6 +31,7 @@ class Partition():
> > > > self.extra_space = args.extra_space
> > > > self.exclude_path = args.exclude_path
> > > > self.include_path = args.include_path
> > > > + self.embed_rootfs = args.embed_rootfs
> > > > self.fsopts = args.fsopts
> > > > self.fstype = args.fstype
> > > > self.label = args.label
> > > > diff --git a/scripts/lib/wic/plugins/source/rootfs.py b/scripts/lib/wic/plugins/source/rootfs.py
> > > > index 40419a64b3..16359601dc 100644
> > > > --- a/scripts/lib/wic/plugins/source/rootfs.py
> > > > +++ b/scripts/lib/wic/plugins/source/rootfs.py
> > > > @@ -80,7 +80,7 @@ class RootfsPlugin(SourcePlugin):
> > > >
> > > > new_rootfs = None
> > > > # Handle excluded paths.
> > > > - if part.exclude_path or part.include_path:
> > > > + if part.exclude_path or part.include_path or part.embed_rootfs:
> > > > # We need a new rootfs directory we can delete files from. Copy to
> > > > # workdir.
> > > > new_rootfs = os.path.realpath(os.path.join(cr_workdir, "rootfs%d" % part.lineno))
> > > > @@ -100,6 +100,24 @@ class RootfsPlugin(SourcePlugin):
> > > > for path in part.include_path or []:
> > > > copyhardlinktree(path, new_rootfs)
> > > >
> > > > + for embed in part.embed_rootfs or []:
> > > > + [embed_rootfs, path] = embed.split(":")
> > > > + #we need to remove the initial / for os.path.join to work
> > > > + if os.path.isabs(path):
> > > > + path = path[1:]
> > > > + if embed_rootfs in krootfs_dir:
> > > > + embed_rootfs = krootfs_dir[embed_rootfs]
> > > > + embed_rootfs = cls.__get_rootfs_dir(embed_rootfs)
> > > > + tar_file = os.path.realpath(os.path.join(cr_workdir, "aux.tar"))
> > > > + tar_cmd = "%s tar cpf %s -C %s ." % (cls.__get_pseudo(native_sysroot,
> > > > + embed_rootfs), tar_file, embed_rootfs)
> > > > + exec_native_cmd(tar_cmd, native_sysroot)
> > > > + untar_cmd = "%s tar xf %s -C %s ." % (cls.__get_pseudo(native_sysroot, new_rootfs),
> > > > + tar_file, os.path.join(new_rootfs, path))
> > > > + exec_native_cmd(untar_cmd, native_sysroot,
> > > > + cls.__get_pseudo(native_sysroot, new_rootfs))
> > > > + os.remove(tar_file)
> > > > +
> > >
> > > Why are you using an intermediate tar file here?
> >
> > For the permissions :(
>
> Your previous patch handled this using 'pseudo -B'. It would be good to be
> consistent if possible - either use an intermediate tar file in all cases if
> it's necessary or use 'pseudo -B' in all cases.
Unfortunately, you cannot use pseudo -B in this case.
You use pseudo -B when you move one pseudo-aware partition to
somewhere else. But now we are merging two pseudo-aware partitions.
Also I would not use the intermediate tar on the first place because
it is a waste of space + cpu resources. Copyhardlink is the right
tool
>
> --
> Paul Barker
> Konsulko Group
--
Ricardo Ribalda
More information about the Openembedded-core
mailing list