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

[Jens Wiklander]

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

Signed-off-by: Jens Wiklander <jens.wiklan...@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");
+
        return 0;
-err:
-       pool->ops->destroy_pool(pool);
-       return rc;
 }
 
 static int optee_probe(struct platform_device *pdev)
-- 
2.43.0