Add support of cancellation request to the TEE kernel internal
client interface. Can be used by software TPM drivers, that leverage
TEE under the hood (for instance TPM2.0 mobile profile), for requesting
cancellation of time-consuming operations (RSA key-pair generation etc.).

Signed-off-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

Introduce a generic TEE bus driver concept for TEE based kernel drivers
which would like to communicate with TEE based devices/services. Also
add support in module device table for these new TEE based devices.

In this TEE bus concept, devices/services are identified via Universally
Unique Identifier (UUID) and drivers register a table of device UUIDs
which they can support.

So this TEE bus framework registers following apis:
- match(): Iterates over the driver UUID table to find a corresponding
  match for device UUID. If a match is found, then this particular device
  is probed via corresponding probe api registered by the driver. This
  process happens whenever a device or a driver is registered with TEE
  bus.
- uevent(): Notifies user-space (udev) whenever a new device is registered
  on this bus for auto-loading of modularized drivers.

Also this framework allows for device enumeration to be specific to
corresponding TEE implementation like OP-TEE etc.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

This flag indicates that requests in this context should not wait for
tee-supplicant daemon to be started if not present and just return
with an error code. It is needed for requests which should be
non-blocking in nature like ones arising from TEE based kernel drivers
or any in kernel api that uses TEE internal client interface.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

Adds a kernel internal TEE client interface to be used by other drivers.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Zeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

This pull request updates the previous tee-drv-dynamic-shm-for-v4.16 pull
request with five new patches fixing review comments and errors.

Apart from three small fixes there's two larger patches that in the end
checks that memory to be registered really is normal cached memory.

* tag 'tee-drv-dynamic-shm+fixes-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: shm: Potential NULL dereference calling tee_shm_register()
  tee: shm: don't put_page on null shm->pages
  tee: shm: make function __tee_shm_alloc static
  tee: optee: check type of registered shared memory
  tee: add start argument to shm_register callback

Signed-off-by: Olof Johansson <olof@lixom.net>

Adds a start argument to the shm_register callback to allow the callback
to check memory type of the passed pages.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

Pull "tee dynamic shm for v4.16" from Jens Wiklander:

This pull request 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 pull request adds generic register/unregister
interface to tee subsystem. The second part adds 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.

This change is backwards compatible allowing older secure world or
user space to work with newer kernels and vice versa.

[1] https://www.globalplatform.org/specificationsdevice.asp

* tag 'tee-drv-dynamic-shm-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: shm: inline tee_shm_get_id()
  tee: use reference counting for tee_context
  tee: optee: enable dynamic SHM support
  tee: optee: add optee-specific shared pool implementation
  tee: optee: store OP-TEE capabilities in private data
  tee: optee: add registered buffers handling into RPC calls
  tee: optee: add registered shared parameters handling
  tee: optee: add shared buffer registration functions
  tee: optee: add page list manipulation functions
  tee: optee: Update protocol definitions
  tee: shm: add page accessor functions
  tee: shm: add accessors for buffer size and page offset
  tee: add register user memory
  tee: flexible shared memory pool creation

Now, when struct tee_shm is defined in public header,
we can inline small getter functions like this one.

Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

We need to ensure that tee_context is present until last
shared buffer will be freed.

Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

In order to register a shared buffer in TEE, we need accessor
function that return list of pages for that buffer.

Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>