Merge tag 'tee-qcomtee-for-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jenswi/linux-tee into soc/drivers

Add Qualcomm TEE driver (QTEE)

This introduces a Trusted Execution Environment (TEE) driver for
Qualcomm TEE (QTEE).

QTEE enables Trusted Applications (TAs) and services to run securely. It
uses an object-based interface, where each service is an object with
sets of operations.

Kernel and userspace services are also available to QTEE through a
similar approach. QTEE makes callback requests that are converted into
object invocations. These objects can represent services within the
kernel or userspace process.

We extend the TEE subsystem to understand object parameters and an ioctl
call so client can invoke objects in QTEE:
  - TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_*
  - TEE_IOC_OBJECT_INVOKE

The existing ioctl calls TEE_IOC_SUPPL_RECV and TEE_IOC_SUPPL_SEND are
used for invoking services in the userspace process by QTEE.

The TEE backend driver uses the QTEE Transport Message to communicate
with QTEE. Interactions through the object INVOKE interface are
translated into QTEE messages. Likewise, object invocations from QTEE
for userspace objects are converted into SEND/RECV ioctl calls to
supplicants.

* tag 'tee-qcomtee-for-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jenswi/linux-tee:
  Documentation: tee: Add Qualcomm TEE driver
  tee: qcom: enable TEE_IOC_SHM_ALLOC ioctl
  tee: qcom: add primordial object
  tee: add Qualcomm TEE driver
  tee: increase TEE_MAX_ARG_SIZE to 4096
  tee: add TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF
  tee: add TEE_IOCTL_PARAM_ATTR_TYPE_UBUF
  tee: add close_context to TEE driver operation
  tee: allow a driver to allocate a tee_device without a pool

Link: https://lore.kernel.org/r/20250915174957.GA2040478@rayden
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

2 files changed, 64 insertions, 2 deletions

diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
index 7b0c1da2ca6c..1f3e5dad6d0d 100644
--- a/include/linux/tee_core.h
+++ b/include/linux/tee_core.h
@@ -76,22 +76,30 @@ struct tee_device {
 /**
  * struct tee_driver_ops - driver operations vtable
  * @get_version:	returns version of driver
- * @open:		called when the device file is opened
- * @release:		release this open file
+ * @open:		called for a context when the device file is opened
+ * @close_context:	called when the device file is closed
+ * @release:		called to release the context
  * @open_session:	open a new session
  * @close_session:	close a session
  * @system_session:	declare session as a system session
  * @invoke_func:	invoke a trusted function
+ * @object_invoke_func:	invoke a TEE object
  * @cancel_req:		request cancel of an ongoing invoke or open
  * @supp_recv:		called for supplicant to get a command
  * @supp_send:		called for supplicant to send a response
  * @shm_register:	register shared memory buffer in TEE
  * @shm_unregister:	unregister shared memory buffer in TEE
+ *
+ * The context given to @open might last longer than the device file if it is
+ * tied to other resources in the TEE driver. @close_context is called when the
+ * client closes the device file, even if there are existing references to the
+ * context. The TEE driver can use @close_context to start cleaning up.
  */
 struct tee_driver_ops {
 	void (*get_version)(struct tee_device *teedev,
 			    struct tee_ioctl_version_data *vers);
 	int (*open)(struct tee_context *ctx);
+	void (*close_context)(struct tee_context *ctx);
 	void (*release)(struct tee_context *ctx);
 	int (*open_session)(struct tee_context *ctx,
 			    struct tee_ioctl_open_session_arg *arg,
@@ -101,6 +109,9 @@ struct tee_driver_ops {
 	int (*invoke_func)(struct tee_context *ctx,
 			   struct tee_ioctl_invoke_arg *arg,
 			   struct tee_param *param);
+	int (*object_invoke_func)(struct tee_context *ctx,
+				  struct tee_ioctl_object_invoke_arg *arg,
+				  struct tee_param *param);
 	int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
 	int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
 			 struct tee_param *param);
@@ -201,6 +212,24 @@ int tee_device_register_dma_heap(struct tee_device *teedev,
 void tee_device_put_all_dma_heaps(struct tee_device *teedev);
 
 /**
+ * tee_device_get() - Increment the user count for a tee_device
+ * @teedev: Pointer to the tee_device
+ *
+ * If tee_device_unregister() has been called and the final user of @teedev
+ * has already released the device, this function will fail to prevent new users
+ * from accessing the device during the unregistration process.
+ *
+ * Returns: true if @teedev remains valid, otherwise false
+ */
+bool tee_device_get(struct tee_device *teedev);
+
+/**
+ * tee_device_put() - Decrease the user count for a tee_device
+ * @teedev: pointer to the tee_device
+ */
+void tee_device_put(struct tee_device *teedev);
+
+/**
  * tee_device_set_dev_groups() - Set device attribute groups
  * @teedev:	Device to register
  * @dev_groups: Attribute groups
@@ -374,4 +403,25 @@ struct tee_context *teedev_open(struct tee_device *teedev);
  */
 void teedev_close_context(struct tee_context *ctx);
 
+/**
+ * teedev_ctx_get() - Increment the reference count of a context
+ * @ctx: Pointer to the context
+ *
+ * This function increases the refcount of the context, which is tied to
+ * resources shared by the same tee_device. During the unregistration process,
+ * the context may remain valid even after tee_device_unregister() has returned.
+ *
+ * Users should ensure that the context's refcount is properly decreased before
+ * calling tee_device_put(), typically within the context's release() function.
+ * Alternatively, users can call tee_device_get() and teedev_ctx_get() together
+ * and release them simultaneously (see shm_alloc_helper()).
+ */
+void teedev_ctx_get(struct tee_context *ctx);
+
+/**
+ * teedev_ctx_put() - Decrease reference count on a context
+ * @ctx: pointer to the context
+ */
+void teedev_ctx_put(struct tee_context *ctx);
+
 #endif /*__TEE_CORE_H*/
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 824f1251de60..88a6f9697c89 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -82,6 +82,16 @@ struct tee_param_memref {
 	struct tee_shm *shm;
 };
 
+struct tee_param_ubuf {
+	void __user *uaddr;
+	size_t size;
+};
+
+struct tee_param_objref {
+	u64 id;
+	u64 flags;
+};
+
 struct tee_param_value {
 	u64 a;
 	u64 b;
@@ -92,6 +102,8 @@ struct tee_param {
 	u64 attr;
 	union {
 		struct tee_param_memref memref;
+		struct tee_param_objref objref;
+		struct tee_param_ubuf ubuf;
 		struct tee_param_value value;
 	} u;
 };