init: boot to device-mapper targets without an initr*
On Fri, 14 May 2010 20:41:41 -0500 Will Drewry wrote:
> Add a dm= kernel parameter modeled after the md= parameter from
> do_mounts_md. It allows for device-mapper targets to be configured at
> boot time for use early in the boot process (as the root device or
documentation needs to be added to Documentation/kernel-parameters.txt and/or
> The format is dm="name uuid ro,table line 1,table line 2,...". The
> parser expects the comma to be safe to use as a newline substitute but,
> otherwise, uses the normal separator of space. Some attempt has been
> made to make it forgiving of additional spaces (using skip_spaces()).
This "space in the arg string" has been tested, right?
It seems a bit odd to me. Most kernel parameter strings that I am familiar with
use punctuation for separating parameter parts.
> A mapped device created during boot will be assigned a minor of 0 and
> may be access via /dev/dm-0.
> An example dm-linear root with no uuid may look like:
> root=/dev/dm-0 dm="lroot none 0, 0 4096 linear 98:16 0, 4096 4096 linear 98:32 0"
> Once udev is started, /dev/dm-0 will become /dev/mapper/lroot.
> Signed-off-by: Will Drewry <firstname.lastname@example.org>
> init/Makefile | 1 +
> init/do_mounts.c | 1 +
> init/do_mounts.h | 10 ++
> init/do_mounts_dm.c | 353 ++++++++++++++++++++++++++++++++++++++++++++++++++ +
> 4 files changed, 365 insertions(+), 0 deletions(-)
> create mode 100644 init/do_mounts_dm.c
*** Remember to use Documentation/SubmitChecklist when testing your code ***
dm-devel mailing list