[PATCH v9 9/9] optee: smc abi: dynamic protected memory allocation

[Jens Wiklander <jens.wiklander@linaro.org>]

Add support in the OP-TEE backend driver for dynamic protected memory
allocation using the SMC ABI.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
---
 drivers/tee/optee/smc_abi.c | 102 ++++++++++++++++++++++++++++++------
 1 file changed, 85 insertions(+), 17 deletions(-)

diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index f3cae8243785..6b3fbe7f0909 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -965,6 +965,70 @@ static int optee_smc_do_call_with_arg(struct tee_context *ctx,
 	return rc;
 }
 
+static int optee_smc_lend_protmem(struct optee *optee, struct tee_shm *protmem,
+				  u16 *end_points, unsigned int ep_count,
+				  u32 use_case)
+{
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *msg_arg;
+	struct tee_shm *shm;
+	u_int offs;
+	int rc;
+
+	msg_arg = optee_get_msg_arg(optee->ctx, 2, &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_LEND_PROTMEM;
+	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
+	msg_arg->params[0].u.value.a = use_case;
+	msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT;
+	msg_arg->params[1].u.tmem.buf_ptr = protmem->paddr;
+	msg_arg->params[1].u.tmem.size = protmem->size;
+	msg_arg->params[1].u.tmem.shm_ref = (u_long)protmem;
+
+	rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false);
+	if (rc)
+		goto out;
+	if (msg_arg->ret != TEEC_SUCCESS) {
+		rc = -EINVAL;
+		goto out;
+	}
+	protmem->sec_world_id = (u_long)protmem;
+
+out:
+	optee_free_msg_arg(optee->ctx, entry, offs);
+	return rc;
+}
+
+static int optee_smc_reclaim_protmem(struct optee *optee,
+				     struct tee_shm *protmem)
+{
+	struct optee_shm_arg_entry *entry;
+	struct optee_msg_arg *msg_arg;
+	struct tee_shm *shm;
+	u_int offs;
+	int rc;
+
+	msg_arg = optee_get_msg_arg(optee->ctx, 1, &entry, &shm, &offs);
+	if (IS_ERR(msg_arg))
+		return PTR_ERR(msg_arg);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_RECLAIM_PROTMEM;
+	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
+	msg_arg->params[0].u.rmem.shm_ref = (u_long)protmem;
+
+	rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false);
+	if (rc)
+		goto out;
+	if (msg_arg->ret != TEEC_SUCCESS)
+		rc = -EINVAL;
+
+out:
+	optee_free_msg_arg(optee->ctx, entry, offs);
+	return rc;
+}
+
 /*
  * 5. Asynchronous notification
  */
@@ -1216,6 +1280,8 @@ static const struct optee_ops optee_ops = {
 	.do_call_with_arg = optee_smc_do_call_with_arg,
 	.to_msg_param = optee_to_msg_param,
 	.from_msg_param = optee_from_msg_param,
+	.lend_protmem = optee_smc_lend_protmem,
+	.reclaim_protmem = optee_smc_reclaim_protmem,
 };
 
 static int enable_async_notif(optee_invoke_fn *invoke_fn)
@@ -1586,11 +1652,14 @@ static inline int optee_load_fw(struct platform_device *pdev,
 
 static int optee_protmem_pool_init(struct optee *optee)
 {
+	bool protm = optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_PROTMEM;
+	bool dyn_protm = optee->smc.sec_caps &
+			 OPTEE_SMC_SEC_CAP_DYNAMIC_PROTMEM;
 	enum tee_dma_heap_id heap_id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY;
-	struct tee_protmem_pool *pool;
-	int rc;
+	struct tee_protmem_pool *pool = ERR_PTR(-EINVAL);
+	int rc = -EINVAL;
 
-	if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_PROTMEM) {
+	if (protm) {
 		union {
 			struct arm_smccc_res smccc;
 			struct optee_smc_get_protmem_config_result result;
@@ -1598,26 +1667,26 @@ static int optee_protmem_pool_init(struct optee *optee)
 
 		optee->smc.invoke_fn(OPTEE_SMC_GET_PROTMEM_CONFIG, 0, 0, 0, 0,
 				     0, 0, 0, &res.smccc);
-		if (res.result.status != OPTEE_SMC_RETURN_OK) {
-			pr_err("Secure Data Path service not available\n");
-			return 0;
-		}
-		rc = optee_set_dma_mask(optee, res.result.pa_width);
+		if (res.result.status == OPTEE_SMC_RETURN_OK)
+			rc = optee_set_dma_mask(optee, res.result.pa_width);
 		if (!rc)
 			pool = tee_protmem_static_pool_alloc(res.result.start,
 							     res.result.size);
-		if (IS_ERR(pool))
-			return PTR_ERR(pool);
+	}
 
+	if (dyn_protm && IS_ERR(pool))
+		pool = optee_protmem_alloc_dyn_pool(optee, heap_id);
+
+	if (!IS_ERR(pool)) {
 		rc = tee_device_register_dma_heap(optee->teedev, heap_id, pool);
 		if (rc)
-			goto err;
+			pool->ops->destroy_pool(pool);
 	}
 
+	if (protm || dyn_protm)
+		return rc;
+
 	return 0;
-err:
-	pool->ops->destroy_pool(pool);
-	return rc;
 }
 
 static int optee_probe(struct platform_device *pdev)
@@ -1788,9 +1857,8 @@ static int optee_probe(struct platform_device *pdev)
 		pr_info("Asynchronous notifications enabled\n");
 	}
 
-	rc = optee_protmem_pool_init(optee);
-	if (rc)
-		goto err_notif_uninit;
+	if (optee_protmem_pool_init(optee))
+		pr_info("Protected memory service not available\n");
 
 	/*
 	 * Ensure that there are no pre-existing shm objects before enabling
-- 
2.43.0