Re: [PATCH v2 0/4] rpmb subsystem, uapi and virtio-rpmb driver

["Alex Bennée" <alex.bennee@linaro.org>]

Alex Bennée <alex.bennee@linaro.org> writes:

> Hi,
>
> This is another attempt to come up with an RPMB API for the kernel.
> The last discussion of this was in the thread:

Ping?

Any other comments or reviews? Is there a desire to make other devices
that provide RPMB functionality visible via a common API?

>
>   Subject: [RFC PATCH  0/5] RPMB internal and user-space API + WIP virtio-rpmb frontend
>   Date: Wed,  3 Mar 2021 13:54:55 +0000
>   Message-Id: <20210303135500.24673-1-alex.bennee@linaro.org>
>
> The series provides for the RPMB sub-system, a new chardev API driven
> by ioctls and a full multi-block capable virtio-rpmb driver. You can
> find a working vhost-user backend in my QEMU branch here:
>
>   https://github.com/stsquad/qemu/commits/virtio/vhost-user-rpmb-v2
>
> The branch is a little messy but I'll be posting a cleaned up version
> in the following weeks. The only real changes to the backend is the
> multi-block awareness and some tweaks to deal with QEMU internals
> handling VirtIO config space messages which weren't previously
> exercised. The test.sh script in tools/rpmb works through the various
> transactions but isn't comprehensive.
>
> Changes since the last posting:
>
>   - frame construction is mostly back in userspace
>
>   The previous discussion showed there wasn't any appetite for using
>   the kernels keyctl() interface so userspace yet again takes
>   responsibility for constructing most* frames. Currently these are
>   all pure virtio-rpmb frames but the code is written so we can plug
>   in additional frame types. The virtio-rpmb driver does some
>   validation and in some cases (* read-blocks) constructs the request
>   frame in the driver. It would take someone implementing a driver for
>   another RPMB device type to see if this makes sense.
>
>   - user-space interface is still split across several ioctls
>
>   Although 3 of the ioctls share the common rpmb_ioc_reqresp_cmd
>   structure it does mean things like capacity, write_count and
>   read_blocks can have their own structure associated with the
>   command.
>
> As before I shall follow up with the QEMU based vhost-user backend and
> hopefully a rust-vmm re-implementation. However I've no direct
> interest in implementing the interfaces to real hardware. I leave that
> to people who have access to such things and are willing to take up
> the maintainer burden if this is merged.
>
> Regards,
>
> Alex
>     
>
> Alex Bennée (4):
>   rpmb: add Replay Protected Memory Block (RPMB) subsystem
>   char: rpmb: provide a user space interface
>   rpmb: create virtio rpmb frontend driver
>   tools rpmb: add RPBM access tool
>
>  .../userspace-api/ioctl/ioctl-number.rst      |    1 +
>  MAINTAINERS                                   |    9 +
>  drivers/Kconfig                               |    2 +
>  drivers/Makefile                              |    1 +
>  drivers/rpmb/Kconfig                          |   28 +
>  drivers/rpmb/Makefile                         |    9 +
>  drivers/rpmb/cdev.c                           |  309 +++++
>  drivers/rpmb/core.c                           |  439 +++++++
>  drivers/rpmb/rpmb-cdev.h                      |   17 +
>  drivers/rpmb/virtio_rpmb.c                    |  518 ++++++++
>  include/linux/rpmb.h                          |  182 +++
>  include/uapi/linux/rpmb.h                     |   99 ++
>  include/uapi/linux/virtio_rpmb.h              |   54 +
>  tools/Makefile                                |   16 +-
>  tools/rpmb/.gitignore                         |    2 +
>  tools/rpmb/Makefile                           |   41 +
>  tools/rpmb/key                                |    1 +
>  tools/rpmb/rpmb.c                             | 1083 +++++++++++++++++
>  tools/rpmb/test.sh                            |   22 +
>  19 files changed, 2828 insertions(+), 5 deletions(-)
>  create mode 100644 drivers/rpmb/Kconfig
>  create mode 100644 drivers/rpmb/Makefile
>  create mode 100644 drivers/rpmb/cdev.c
>  create mode 100644 drivers/rpmb/core.c
>  create mode 100644 drivers/rpmb/rpmb-cdev.h
>  create mode 100644 drivers/rpmb/virtio_rpmb.c
>  create mode 100644 include/linux/rpmb.h
>  create mode 100644 include/uapi/linux/rpmb.h
>  create mode 100644 include/uapi/linux/virtio_rpmb.h
>  create mode 100644 tools/rpmb/.gitignore
>  create mode 100644 tools/rpmb/Makefile
>  create mode 100644 tools/rpmb/key
>  create mode 100644 tools/rpmb/rpmb.c
>  create mode 100755 tools/rpmb/test.sh


-- 
Alex Bennée