On Wed, Nov 29, 2017 at 02:48:24PM +0200, Volodymyr Babchuk wrote:
From: Volodymyr Babchuk vlad.babchuk@gmail.com
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 ynorov@caviumnetworks.com and Mark Rutland mark.rutland@arm.com 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