Commit Graph

8 Commits

Author SHA1 Message Date
Sumit Garg
0439fcff30 tee: Refactor TEE subsystem header files
Since commit 25559c22ce ("tee: add kernel internal client interface"),
it has been a common include/linux/tee_drv.h header file which is shared
to hold TEE subsystem internal bits along with the APIs exposed to the
TEE client drivers. However, this practice is prone to TEE subsystem
internal APIs abuse and especially so with the new TEE implementation
drivers being added to reuse existing functionality.

In order to address this split TEE subsystem internal bits as a separate
header file: include/linux/tee_core.h which should be the one used by
TEE implementation drivers. With that include/linux/tee_drv.h lists only
APIs exposed by TEE subsystem to the TEE client drivers.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2024-04-03 09:19:31 +02:00
Jens Wiklander
a45ea4efa3 tee: refactor TEE_SHM_* flags
Removes the redundant TEE_SHM_DMA_BUF, TEE_SHM_EXT_DMA_BUF,
TEE_SHM_MAPPED and TEE_SHM_KERNEL_MAPPED flags.

TEE_SHM_REGISTER is renamed to TEE_SHM_DYNAMIC in order to better
match its usage.

Assigns new values to the remaining flags to void gaps.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2022-02-16 07:49:41 +01:00
Jens Wiklander
d88e0493a0 tee: simplify shm pool handling
Replaces the shared memory pool based on two pools with a single pool.
The alloc() function pointer in struct tee_shm_pool_ops gets another
parameter, align. This makes it possible to make less than page aligned
allocations from the optional reserved shared memory pool while still
making user space allocations page aligned. With in practice unchanged
behaviour using only a single pool for bookkeeping.

The allocation algorithm in the static OP-TEE shared memory pool is
changed from best-fit to first-fit since only the latter supports an
alignment parameter. The best-fit algorithm was previously the default
choice and not a conscious one.

The optee and amdtee drivers are updated as needed to work with this
changed pool handling.

This also removes OPTEE_SHM_NUM_PRIV_PAGES which becomes obsolete with
this change as the private pages can be mixed with the payload pages.

The OP-TEE driver changes minimum alignment for argument struct from 8
bytes to 512 bytes. A typical OP-TEE private shm allocation is 224 bytes
(argument struct with 6 parameters, needed for open session). So with an
alignment of 512 well waste a bit more than 50%. Before this we had a
single page reserved for this so worst case usage compared to that would
be 3 pages instead of 1 page. However, this worst case only occurs if
there is a high pressure from multiple threads on secure world. All in
all this should scale up and down better than fixed boundaries.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2022-02-16 07:49:41 +01:00
Jens Wiklander
71cc47d4cc tee: add tee_shm_alloc_user_buf()
Adds a new function tee_shm_alloc_user_buf() for user mode allocations,
replacing passing the flags TEE_SHM_MAPPED | TEE_SHM_DMA_BUF to
tee_shm_alloc().

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2022-02-16 07:49:41 +01:00
Jens Wiklander
f41b6be1eb tee: remove unused tee_shm_pool_alloc_res_mem()
None of the drivers in the TEE subsystem uses
tee_shm_pool_alloc_res_mem() so remove the function.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2022-02-16 07:49:41 +01:00
Thomas Gleixner
9c92ab6191 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282
Based on 1 normalized pattern(s):

  this software is licensed under the terms of the gnu general public
  license version 2 as published by the free software foundation and
  may be copied distributed and modified under those terms this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Jens Wiklander
e2aca5d892 tee: flexible shared memory pool creation
Makes creation of shm pools more flexible by adding new more primitive
functions to allocate a shm pool. This makes it easier to add driver
specific shm pool management.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
2017-12-15 12:37:29 +01:00
Jens Wiklander
967c9cca2c tee: generic TEE subsystem
Initial patch for generic TEE subsystem.
This subsystem provides:
* Registration/un-registration of TEE drivers.
* Shared memory between normal world and secure world.
* Ioctl interface for interaction with user space.
* Sysfs implementation_id of TEE driver

A TEE (Trusted Execution Environment) driver is a driver that interfaces
with a trusted OS running in some secure environment, for example,
TrustZone on ARM cpus, or a separate secure co-processor etc.

The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.

This patch builds on other similar implementations trying to solve
the same problem:
* "optee_linuxdriver" by among others
  Jean-michel DELORME<jean-michel.delorme@st.com> and
  Emmanuel MICHEL <emmanuel.michel@st.com>
* "Generic TrustZone Driver" by Javier González <javier@javigon.com>

Acked-by: Andreas Dannenberg <dannenberg@ti.com>
Tested-by: Jerome Forissier <jerome.forissier@linaro.org> (HiKey)
Tested-by: Volodymyr Babchuk <vlad.babchuk@gmail.com> (RCAR H3)
Tested-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2017-03-09 15:42:33 +01:00