kernel/linux.git/drivers/tee/tee_private.h, branch v7.0.10

tee: add close_context to TEE driver operation

2025-09-15T15:34:06+00:00

The tee_context can be used to manage TEE user resources, including those allocated by the driver for the TEE on behalf of the user. The release() callback is invoked only when all resources, such as tee_shm, are released and there are no references to the tee_context. When a user closes the device file, the driver should notify the TEE to release any resources it may hold and drop the context references. To achieve this, a close_context() callback is introduced to initiate resource release in the TEE driver when the device file is closed. Relocate teedev_ctx_get, teedev_ctx_put, tee_device_get, and tee_device_get functions to tee_core.h to make them accessible outside the TEE subsystem. Reviewed-by: Sumit Garg Tested-by: Neil Armstrong Tested-by: Harshal Dev Signed-off-by: Amirreza Zarrabi Signed-off-by: Jens Wiklander

tee: new ioctl to a register tee_shm from a dmabuf file descriptor

2025-09-11T09:22:29+00:00

Add a userspace API to create a tee_shm object that refers to a dmabuf reference. Userspace registers the dmabuf file descriptor as in a tee_shm object. The registration is completed with a tee_shm returned file descriptor. Userspace is free to close the dmabuf file descriptor after it has been registered since all the resources are now held via the new tee_shm object. Closing the tee_shm file descriptor will eventually release all resources used by the tee_shm object when all references are released. The new IOCTL, TEE_IOC_SHM_REGISTER_FD, supports dmabuf references to physically contiguous memory buffers. Dmabuf references acquired from the TEE DMA-heap can be used as protected memory for Secure Video Path and such use cases. It depends on the TEE and the TEE driver if dmabuf references acquired by other means can be used. A new tee_shm flag is added to identify tee_shm objects built from a registered dmabuf, TEE_SHM_DMA_BUF. Signed-off-by: Etienne Carriere Signed-off-by: Olivier Masse Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander

tee: implement protected DMA-heap

2025-09-11T09:22:20+00:00

Implement DMA heap for protected DMA-buf allocation in the TEE subsystem. Protected memory refers to memory buffers behind a hardware enforced firewall. It is not accessible to the kernel during normal circumstances but rather only accessible to certain hardware IPs or CPUs executing in higher or differently privileged mode than the kernel itself. This interface allows to allocate and manage such protected memory buffers via interaction with a TEE implementation. The protected memory is allocated for a specific use-case, like Secure Video Playback, Trusted UI, or Secure Video Recording where certain hardware devices can access the memory. The DMA-heaps are enabled explicitly by the TEE backend driver. The TEE backend drivers needs to implement protected memory pool to manage the protected memory. Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander

tee: Refactor TEE subsystem header files

2024-04-03T07:19:31+00:00

Since commit 25559c22cef8 ("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 Signed-off-by: Balint Dobszay Signed-off-by: Jens Wiklander

tee: Remove unused declarations

2023-09-13T06:16:24+00:00

Commit 4fb0a5eb364d ("tee: add OP-TEE driver") declared but never implemented optee_supp_read()/optee_supp_write(). Commit 967c9cca2cc5 ("tee: generic TEE subsystem") never implemented tee_shm_init(). Signed-off-by: Yue Haibing Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander

tee: add tee_shm_register_{user,kernel}_buf()

2022-02-16T06:49:41+00:00

Adds the two new functions tee_shm_register_user_buf() and tee_shm_register_kernel_buf() which should be used instead of the old tee_shm_register(). This avoids having the caller supplying the flags parameter which exposes a bit more than desired of the internals of the TEE subsystem. Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander

tee: simplify shm pool handling

2022-02-16T06:49:41+00:00

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 Signed-off-by: Jens Wiklander

tee: add tee_shm_alloc_user_buf()

2022-02-16T06:49:41+00:00

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 Signed-off-by: Jens Wiklander

tee: don't assign shm id for private shms

2020-02-28T12:37:42+00:00

Private shared memory object must not be referenced from user space. To guarantee that, don't assign an id to shared memory objects which are driver private. Signed-off-by: Jens Wiklander

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

2019-06-05T15:36:37+00:00

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 Reviewed-by: Alexios Zavras Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de Signed-off-by: Greg Kroah-Hartman