Re: [PATCH v6 10/10] optee: smc abi: dynamic restricted memory allocation

On Wed, Mar 05, 2025 at 02:04:16PM +0100, Jens Wiklander wrote:

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

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

drivers/tee/optee/smc_abi.c | 96 +++++++++++++++++++++++++++++++------ 1 file changed, 81 insertions(+), 15 deletions(-)

diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index a14ff0b7d3b3..aa574ee6e277 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -1001,6 +1001,69 @@ static int optee_smc_do_call_with_arg(struct tee_context *ctx, return rc; } +static int optee_smc_lend_rstmem(struct optee *optee, struct tee_shm *rstmem,

• 		 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_RSTMEM;
• 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 = rstmem->paddr;
• msg_arg->params[1].u.tmem.size = rstmem->size;
• msg_arg->params[1].u.tmem.shm_ref = (u_long)rstmem;
• 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;
  

• }
• rstmem->sec_world_id = (u_long)rstmem;

+out:

• optee_free_msg_arg(optee->ctx, entry, offs);
• return rc;

+}

+static int optee_smc_reclaim_rstmem(struct optee *optee, struct tee_shm *rstmem) +{

• 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_RSTMEM;
• msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
• msg_arg->params[0].u.rmem.shm_ref = (u_long)rstmem;
• 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

*/ @@ -1252,6 +1315,8 @@ 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_rstmem = optee_smc_lend_rstmem,
• .reclaim_rstmem = optee_smc_reclaim_rstmem,

}; static int enable_async_notif(optee_invoke_fn *invoke_fn) @@ -1622,11 +1687,13 @@ static inline int optee_load_fw(struct platform_device *pdev, static int optee_sdp_pool_init(struct optee *optee) {

• bool sdp = optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_SDP;
• bool dyn_sdp = optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_RSTMEM; enum tee_dma_heap_id heap_id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY;

• struct tee_rstmem_pool *pool;
• int rc;

• struct tee_rstmem_pool *pool = ERR_PTR(-EINVAL);
• int rc = -EINVAL;

• if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_SDP) {

• if (sdp) { union { struct arm_smccc_res smccc; struct optee_smc_get_sdp_config_result result;

@@ -1634,25 +1701,24 @@ static int optee_sdp_pool_init(struct optee *optee) optee->smc.invoke_fn(OPTEE_SMC_GET_SDP_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;
  

• }
  

• if (res.result.status == OPTEE_SMC_RETURN_OK)
  

• 	pool = tee_rstmem_static_pool_alloc(res.result.start,
  

• 					    res.result.size);
  

• }

• pool = tee_rstmem_static_pool_alloc(res.result.start,
  

• 				    res.result.size);
  

• if (IS_ERR(pool))
  

• 	return PTR_ERR(pool);
  

• if (dyn_sdp && IS_ERR(pool))

• pool = optee_rstmem_alloc_cma_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 (rc && (sdp || dyn_sdp))

• pr_err("Secure Data Path service not available\n");
  

Rather than an error message we should just use pr_info().

-Sumit

• return 0;

-err:

• pool->ops->destroy_pool(pool);
• return rc;

} static int optee_probe(struct platform_device *pdev) -- 2.43.0