Re: [PATCH v4 09/11] qcomtee: add primordial object

On Mon, Apr 28, 2025 at 11:06:30PM -0700, Amirreza Zarrabi wrote:

After booting, the kernel provides a static object known as the primordial object. This object is utilized by QTEE for native kernel services such as yield or privileged operations.

Signed-off-by: Amirreza Zarrabi amirreza.zarrabi@oss.qualcomm.com

drivers/tee/qcomtee/Makefile | 1 + drivers/tee/qcomtee/core.c | 19 +++++++--- drivers/tee/qcomtee/primordial_obj.c | 65 +++++++++++++++++++++++++++++++++++ drivers/tee/qcomtee/qcomtee_private.h | 3 ++ 4 files changed, 83 insertions(+), 5 deletions(-)

Looks reasonable to me, feel free to add:

Acked-by: Sumit Garg sumit.garg@oss.qualcomm.com

-Sumit

diff --git a/drivers/tee/qcomtee/Makefile b/drivers/tee/qcomtee/Makefile index 1b14b943e5f5..a3a2d00e83f0 100644 --- a/drivers/tee/qcomtee/Makefile +++ b/drivers/tee/qcomtee/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_QCOMTEE) += qcomtee.o qcomtee-objs += async.o qcomtee-objs += call.o qcomtee-objs += core.o +qcomtee-objs += primordial_obj.o qcomtee-objs += qcom_scm.o qcomtee-objs += release.o qcomtee-objs += shm.o diff --git a/drivers/tee/qcomtee/core.c b/drivers/tee/qcomtee/core.c index ad3b28f32529..a1ac492fd21a 100644 --- a/drivers/tee/qcomtee/core.c +++ b/drivers/tee/qcomtee/core.c @@ -39,10 +39,12 @@ int qcomtee_next_arg_type(struct qcomtee_arg *u, int i, } /*

• • QTEE expects IDs with the QCOMTEE_MSG_OBJECT_NS_BIT set for objects
• • of the QCOMTEE_OBJECT_TYPE_CB type.

• • QTEE expects IDs with QCOMTEE_MSG_OBJECT_NS_BIT set for objects of
• • QCOMTEE_OBJECT_TYPE_CB type. The first ID with QCOMTEE_MSG_OBJECT_NS_BIT
• • set is reserved for the primordial object.
  */

-#define QCOMTEE_OBJECT_ID_START (QCOMTEE_MSG_OBJECT_NS_BIT + 1) +#define QCOMTEE_OBJECT_PRIMORDIAL (QCOMTEE_MSG_OBJECT_NS_BIT) +#define QCOMTEE_OBJECT_ID_START (QCOMTEE_OBJECT_PRIMORDIAL + 1) #define QCOMTEE_OBJECT_ID_END (U32_MAX) #define QCOMTEE_OBJECT_SET(p, type, ...) \ @@ -127,7 +129,9 @@ static void qcomtee_object_release(struct kref *refcount) */ int qcomtee_object_get(struct qcomtee_object *object) {

• if (object != NULL_QCOMTEE_OBJECT && object != ROOT_QCOMTEE_OBJECT)

• if (object != &qcomtee_primordial_object &&

•    object != NULL_QCOMTEE_OBJECT &&
  

•    object != ROOT_QCOMTEE_OBJECT)
  

  return kref_get_unless_zero(&object->refcount);

return 0; @@ -140,7 +144,9 @@ EXPORT_SYMBOL_GPL(qcomtee_object_get); */ void qcomtee_object_put(struct qcomtee_object *object) {

• if (object != NULL_QCOMTEE_OBJECT && object != ROOT_QCOMTEE_OBJECT)

• if (object != &qcomtee_primordial_object &&

•    object != NULL_QCOMTEE_OBJECT &&
  

•    object != ROOT_QCOMTEE_OBJECT)
  

  kref_put(&object->refcount, qcomtee_object_release);

} EXPORT_SYMBOL_GPL(qcomtee_object_put); @@ -222,6 +228,9 @@ static struct qcomtee_object *qcomtee_local_object_get(unsigned int object_id) { struct qcomtee_object *object;

• if (object_id == QCOMTEE_OBJECT_PRIMORDIAL)

• return &qcomtee_primordial_object;
  

• guard(rcu)(); object = xa_load(&xa_qcom_local_objects, object_id); /* It already checks for %NULL_QCOMTEE_OBJECT. */

diff --git a/drivers/tee/qcomtee/primordial_obj.c b/drivers/tee/qcomtee/primordial_obj.c new file mode 100644 index 000000000000..a30967d89c91 --- /dev/null +++ b/drivers/tee/qcomtee/primordial_obj.c @@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0-only +/*

• • Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
• */

+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

+#include <linux/delay.h> +#include "qcomtee_private.h"

+/**

• • DOC: Primordial Object
• • After boot, the kernel provides a static object of type
• • %QCOMTEE_OBJECT_TYPE_CB called the primordial object. This object is used
• • for native kernel services or privileged operations.
• • We support:
• • • %QCOMTEE_OBJECT_OP_YIELD to yield by the thread running in QTEE.
• • • %QCOMTEE_OBJECT_OP_SLEEP to wait for a period of time.
• */

+#define QCOMTEE_OBJECT_OP_YIELD 1 +#define QCOMTEE_OBJECT_OP_SLEEP 2

+static int +qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic,

• 		struct qcomtee_object *primordial_object_unused,
  

• 		u32 op, struct qcomtee_arg *args)
  

+{

• int err = 0;
• switch (op) {
• case QCOMTEE_OBJECT_OP_YIELD:

• cond_resched();
  

• /* No output object. */
  

• oic->data = NULL;
  

• break;
  

• case QCOMTEE_OBJECT_OP_SLEEP:

• /* Check message format matched QCOMTEE_OBJECT_OP_SLEEP op. */
  

• if (qcomtee_args_len(args) != 1 ||
  

•     args[0].type != QCOMTEE_ARG_TYPE_IB ||
  

•     args[0].b.size < sizeof(u32))
  

• 	return -EINVAL;
  

• msleep(*(u32 *)(args[0].b.addr));
  

• /* No output object. */
  

• oic->data = NULL;
  

• break;
  

• default:

• err = -EINVAL;
  

• }
• return err;

+}

+static struct qcomtee_object_operations qcomtee_primordial_obj_ops = {

• .dispatch = qcomtee_primordial_obj_dispatch,

+};

+struct qcomtee_object qcomtee_primordial_object = {

• .name = "primordial",
• .object_type = QCOMTEE_OBJECT_TYPE_CB,
• .ops = &qcomtee_primordial_obj_ops

+}; diff --git a/drivers/tee/qcomtee/qcomtee_private.h b/drivers/tee/qcomtee/qcomtee_private.h index a6f2c0591580..e59cfb3b79dd 100644 --- a/drivers/tee/qcomtee/qcomtee_private.h +++ b/drivers/tee/qcomtee/qcomtee_private.h @@ -219,4 +219,7 @@ int qcomtee_user_object_submit(struct tee_context *ctx, struct tee_param *params, int num_params, int req_id, int errno); +/* (2) Primordial Object. */ +extern struct qcomtee_object qcomtee_primordial_object;

#endif /* QCOMTEE_PRIVATE_H */

-- 2.34.1