From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752664AbdLFOdB (ORCPT ); Wed, 6 Dec 2017 09:33:01 -0500 Received: from mail-lf0-f66.google.com ([209.85.215.66]:37810 "EHLO mail-lf0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752565AbdLFOcr (ORCPT ); Wed, 6 Dec 2017 09:32:47 -0500 X-Google-Smtp-Source: AGs4zMYUQmGLy0+qDFwiE9RUjJOsCeuQBYnrRtOVpX+fH9stYoTnG5poP82EOEBQfYIj3Ce5BluVPQ== Date: Wed, 6 Dec 2017 15:32:42 +0100 From: Jens Wiklander To: Volodymyr Babchuk Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tee-dev@lists.linaro.org, Volodymyr Babchuk Subject: Re: [RESEND PATCH v2 00/14] tee: optee: add dynamic shared memory support Message-ID: <20171206143241.jjk5vq23wqid3woi@jax> References: <1507923164-12796-1-git-send-email-volodymyr_babchuk@epam.com> <1511959718-5421-1-git-send-email-volodymyr_babchuk@epam.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1511959718-5421-1-git-send-email-volodymyr_babchuk@epam.com> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 29, 2017 at 02:48:24PM +0200, Volodymyr Babchuk wrote: > From: Volodymyr Babchuk > > Hello all, > > This is resend of OP-TEE dynamic SHM series. No changes > from last time. Correct version is used in the subject. > > --- > Changes from v1: > > * Added support for 16K and 64K pages. Elaborated commit messages > * More minor changes are described in corresponding patches. > > While this patches are necessary for use OP-TEE in virualized > environment, they are not sufficient. Stuart Yoder was right, when > proposed to make static SHM optional. But that would be a breaking > change, because this will render unusable older client libraries and > supplicants. > > Also, as Mark Rutland pointed, OP-TEE virtualization will need support > from hypervisor side. > > Anyways, those patches allowed me to call OP-TEE from XEN's Dom0 > without remapping static SHM region into Dom0 userspace. > > Also, this patches allow me to share quite big buffers (I tried to use > three 2M buffers at a time). This is imposible with static SHM, > because static SHM on most platforms is only 2M. > > Thanks to Yury Norov and > Mark Rutland for reviewing this patch series. > > --- > v1 cover letter: > This patch series enables dynamic shared memory support in the TEE > subsystem as a whole and in OP-TEE in particular. > > Global Platform TEE specification [1] allows client applications > to register part of own memory as a shared buffer between > application and TEE. This allows fast zero-copy communication between > TEE and REE. But current implementation of TEE in Linux does not support > this feature. > > Also, current implementation of OP-TEE transport uses fixed size > pre-shared buffer for all communications with OP-TEE OS. This is okay > in the most use cases. But this prevents use of OP-TEE in virtualized > environments, because: > a) We can't share the same buffer between different virtual machines > b) Physically contiguous memory as seen by VM can be non-contiguous > in reality (and as seen by OP-TEE OS) due to second stage of > MMU translation. > c) Size of this pre-shared buffer is limited. > > So, first part of this patch series adds generic register/unregister > interface to tee subsystem. Next patches add necessary features > into OP-TEE driver, so it can use not only static pre-shared buffer, > but whole RAM to communicate with OP-TEE OS. > > [1] https://www.globalplatform.org/specificationsdevice.asp > > Jens Wiklander (2): > tee: flexible shared memory pool creation > tee: add register user memory > > Volodymyr Babchuk (12): > tee: shm: add accessors for buffer size and page offset > tee: shm: add page accessor functions > tee: optee: Update protocol definitions > tee: optee: add page list manipulation functions > tee: optee: add shared buffer registration functions > tee: optee: add registered shared parameters handling > tee: optee: add registered buffers handling into RPC calls > tee: optee: store OP-TEE capabilities in private data > tee: optee: add optee-specific shared pool implementation > tee: optee: enable dynamic SHM support > tee: use reference counting for tee_context > tee: shm: inline tee_shm_get_id() > > drivers/tee/optee/Makefile | 1 + > drivers/tee/optee/call.c | 179 +++++++++++++++++++++++++++++- > drivers/tee/optee/core.c | 152 +++++++++++++++++++------ > drivers/tee/optee/optee_msg.h | 38 ++++++- > drivers/tee/optee/optee_private.h | 27 ++++- > drivers/tee/optee/optee_smc.h | 7 ++ > drivers/tee/optee/rpc.c | 77 +++++++++++-- > drivers/tee/optee/shm_pool.c | 75 +++++++++++++ > drivers/tee/optee/shm_pool.h | 23 ++++ > drivers/tee/tee_core.c | 81 ++++++++++++-- > drivers/tee/tee_private.h | 60 +--------- > drivers/tee/tee_shm.c | 227 +++++++++++++++++++++++++++++++------- > drivers/tee/tee_shm_pool.c | 165 ++++++++++++++++----------- > include/linux/tee_drv.h | 183 +++++++++++++++++++++++++++++- > include/uapi/linux/tee.h | 30 +++++ > 15 files changed, 1104 insertions(+), 221 deletions(-) > create mode 100644 drivers/tee/optee/shm_pool.c > create mode 100644 drivers/tee/optee/shm_pool.h > > -- > 2.7.4 > This looks good to me. I've been testing this for quite some time now. If there's no further comments I'll pick it up send it in a pull request to arm-soc. Thanks, Jens