[PATCH v4 6/6] optee: smc abi: dynamic restricted memory allocation

Jens Wiklander
2024-12-17T10:07:42Z

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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 | 74 +++++++++++++++++++++++++++++++++++--
1 file changed, 71 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index f5fd5f1d9a6b..25b02dbbc76e 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -1001,6 +1001,67 @@ 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)
+{
+ 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 = OPTEE_MSG_RSTMEM_SECURE_VIDEO_PLAY;
+ 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;
+ }
+
+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
*/
@@ -1258,6 +1319,8 @@ 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)
@@ -1627,6 +1690,7 @@ static inline int optee_load_fw(struct platform_device *pdev,

static int optee_sdp_pool_init(struct optee *optee)
{
+ bool dyn_sdp = optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_RSTMEM;
bool sdp = optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_SDP;
struct tee_shm_pool *pool;
int rc;
@@ -1634,9 +1698,11 @@ static int optee_sdp_pool_init(struct optee *optee)
/*
* optee_sdp_pools_init() must be called if secure world has any
* SDP capability. If the static carvout is available initialize
- * and add a pool for that.
+ * and add a pool for that. If there's an error from secure world
+ * we complain but don't call optee_sdp_pools_uninit() unless we
+ * know that there is no SDP capability left.
*/
- if (!sdp)
+ if (!dyn_sdp && !sdp)
return 0;

rc = optee_rstmem_pools_init(optee);
@@ -1653,7 +1719,9 @@ static int optee_sdp_pool_init(struct optee *optee)
0, &res.smccc);
if (res.result.status != OPTEE_SMC_RETURN_OK) {
pr_err("Secure Data Path service not available\n");
- goto err;
+ if (!dyn_sdp)
+ goto err;
+ return 0;
}

pool = tee_rstmem_gen_pool_alloc(res.result.start,
--
2.43.0