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

On Mon, May 26, 2025 at 10:13 AM Sumit Garg sumit.garg@kernel.org wrote:

On Tue, May 20, 2025 at 05:16:52PM +0200, Jens Wiklander wrote:

...

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);
  

This change should be folded in patch 7/9.

OK

...

          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");
  

This change can be folded in patch 7/9.

Yes, that makes sense.

Cheers, Jens

Rest looks good to me.

-Sumit

...

  /*
   * Ensure that there are no pre-existing shm objects before enabling

-- 2.43.0