Adds an argument to do_call_with_arg() handler to tell whether the call
is a system call or nor. This change always sets this info to false
hence no functional change.
This change prepares management of system invocation proposed in a later
change.
Co-developed-by: Jens Wiklander <[email protected]>
Signed-off-by: Jens Wiklander <[email protected]>
Signed-off-by: Etienne Carriere <[email protected]>
---
Changes since v4:
- New change, extracted from PATCH v4 1/2 (tee: system invocation") and
revised to cover preparatory changes in optee driver for system session
support with contribution from Jens.
---
drivers/tee/optee/call.c | 22 ++++++++++++++++------
drivers/tee/optee/core.c | 5 +++--
drivers/tee/optee/ffa_abi.c | 3 ++-
drivers/tee/optee/optee_private.h | 7 +++++--
drivers/tee/optee/smc_abi.c | 9 +++++----
5 files changed, 31 insertions(+), 15 deletions(-)
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
index 290b1bb0e9cd..844d2bdc68db 100644
--- a/drivers/tee/optee/call.c
+++ b/drivers/tee/optee/call.c
@@ -328,7 +328,8 @@ int optee_open_session(struct tee_context *ctx,
goto out;
}
- if (optee->ops->do_call_with_arg(ctx, shm, offs)) {
+ if (optee->ops->do_call_with_arg(ctx, shm, offs,
+ sess->use_sys_thread)) {
msg_arg->ret = TEEC_ERROR_COMMUNICATION;
msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
}
@@ -360,7 +361,8 @@ int optee_open_session(struct tee_context *ctx,
return rc;
}
-int optee_close_session_helper(struct tee_context *ctx, u32 session)
+int optee_close_session_helper(struct tee_context *ctx, u32 session,
+ bool system_thread)
{
struct optee *optee = tee_get_drvdata(ctx->teedev);
struct optee_shm_arg_entry *entry;
@@ -374,7 +376,7 @@ int optee_close_session_helper(struct tee_context *ctx, u32 session)
msg_arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
msg_arg->session = session;
- optee->ops->do_call_with_arg(ctx, shm, offs);
+ optee->ops->do_call_with_arg(ctx, shm, offs, system_thread);
optee_free_msg_arg(ctx, entry, offs);
@@ -385,6 +387,7 @@ int optee_close_session(struct tee_context *ctx, u32 session)
{
struct optee_context_data *ctxdata = ctx->data;
struct optee_session *sess;
+ bool system_thread;
/* Check that the session is valid and remove it from the list */
mutex_lock(&ctxdata->mutex);
@@ -394,9 +397,10 @@ int optee_close_session(struct tee_context *ctx, u32 session)
mutex_unlock(&ctxdata->mutex);
if (!sess)
return -EINVAL;
+ system_thread = sess->use_sys_thread;
kfree(sess);
- return optee_close_session_helper(ctx, session);
+ return optee_close_session_helper(ctx, session, system_thread);
}
int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
@@ -408,12 +412,15 @@ int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
struct optee_msg_arg *msg_arg;
struct optee_session *sess;
struct tee_shm *shm;
+ bool system_thread;
u_int offs;
int rc;
/* Check that the session is valid */
mutex_lock(&ctxdata->mutex);
sess = find_session(ctxdata, arg->session);
+ if (sess)
+ system_thread = sess->use_sys_thread;
mutex_unlock(&ctxdata->mutex);
if (!sess)
return -EINVAL;
@@ -432,7 +439,7 @@ int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
if (rc)
goto out;
- if (optee->ops->do_call_with_arg(ctx, shm, offs)) {
+ if (optee->ops->do_call_with_arg(ctx, shm, offs, system_thread)) {
msg_arg->ret = TEEC_ERROR_COMMUNICATION;
msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
}
@@ -457,12 +464,15 @@ int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
struct optee_shm_arg_entry *entry;
struct optee_msg_arg *msg_arg;
struct optee_session *sess;
+ bool system_thread;
struct tee_shm *shm;
u_int offs;
/* Check that the session is valid */
mutex_lock(&ctxdata->mutex);
sess = find_session(ctxdata, session);
+ if (sess)
+ system_thread = sess->use_sys_thread;
mutex_unlock(&ctxdata->mutex);
if (!sess)
return -EINVAL;
@@ -474,7 +484,7 @@ int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
msg_arg->cmd = OPTEE_MSG_CMD_CANCEL;
msg_arg->session = session;
msg_arg->cancel_id = cancel_id;
- optee->ops->do_call_with_arg(ctx, shm, offs);
+ optee->ops->do_call_with_arg(ctx, shm, offs, system_thread);
optee_free_msg_arg(ctx, entry, offs);
return 0;
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 2a258bd3b6b5..d01ca47f7bde 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -129,7 +129,8 @@ int optee_open(struct tee_context *ctx, bool cap_memref_null)
static void optee_release_helper(struct tee_context *ctx,
int (*close_session)(struct tee_context *ctx,
- u32 session))
+ u32 session,
+ bool system_thread))
{
struct optee_context_data *ctxdata = ctx->data;
struct optee_session *sess;
@@ -141,7 +142,7 @@ static void optee_release_helper(struct tee_context *ctx,
list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
list_node) {
list_del(&sess->list_node);
- close_session(ctx, sess->session_id);
+ close_session(ctx, sess->session_id, sess->use_sys_thread);
kfree(sess);
}
kfree(ctxdata);
diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
index 0828240f27e6..52cec9d06041 100644
--- a/drivers/tee/optee/ffa_abi.c
+++ b/drivers/tee/optee/ffa_abi.c
@@ -612,7 +612,8 @@ static int optee_ffa_yielding_call(struct tee_context *ctx,
*/
static int optee_ffa_do_call_with_arg(struct tee_context *ctx,
- struct tee_shm *shm, u_int offs)
+ struct tee_shm *shm, u_int offs,
+ bool system_thread)
{
struct ffa_send_direct_data data = {
.data0 = OPTEE_FFA_YIELDING_CALL_WITH_ARG,
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index 04ae58892608..bdbc0dc293bb 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -130,7 +130,8 @@ struct optee;
*/
struct optee_ops {
int (*do_call_with_arg)(struct tee_context *ctx,
- struct tee_shm *shm_arg, u_int offs);
+ struct tee_shm *shm_arg, u_int offs,
+ bool system_thread);
int (*to_msg_param)(struct optee *optee,
struct optee_msg_param *msg_params,
size_t num_params, const struct tee_param *params);
@@ -180,6 +181,7 @@ struct optee {
struct optee_session {
struct list_head list_node;
u32 session_id;
+ bool use_sys_thread;
};
struct optee_context_data {
@@ -228,7 +230,8 @@ int optee_supp_send(struct tee_context *ctx, u32 ret, u32 num_params,
int optee_open_session(struct tee_context *ctx,
struct tee_ioctl_open_session_arg *arg,
struct tee_param *param);
-int optee_close_session_helper(struct tee_context *ctx, u32 session);
+int optee_close_session_helper(struct tee_context *ctx, u32 session,
+ bool system_thread);
int optee_close_session(struct tee_context *ctx, u32 session);
int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
struct tee_param *param);
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index a1c1fa1a9c28..df77700804e5 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -487,7 +487,7 @@ static int optee_shm_register(struct tee_context *ctx, struct tee_shm *shm,
msg_arg->params->u.tmem.buf_ptr = virt_to_phys(pages_list) |
(tee_shm_get_page_offset(shm) & (OPTEE_MSG_NONCONTIG_PAGE_SIZE - 1));
- if (optee->ops->do_call_with_arg(ctx, shm_arg, 0) ||
+ if (optee->ops->do_call_with_arg(ctx, shm_arg, 0, false) ||
msg_arg->ret != TEEC_SUCCESS)
rc = -EINVAL;
@@ -530,7 +530,7 @@ static int optee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm)
msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
msg_arg->params[0].u.rmem.shm_ref = (unsigned long)shm;
- if (optee->ops->do_call_with_arg(ctx, shm_arg, 0) ||
+ if (optee->ops->do_call_with_arg(ctx, shm_arg, 0, false) ||
msg_arg->ret != TEEC_SUCCESS)
rc = -EINVAL;
out:
@@ -865,7 +865,8 @@ static void optee_handle_rpc(struct tee_context *ctx,
* Returns return code from secure world, 0 is OK
*/
static int optee_smc_do_call_with_arg(struct tee_context *ctx,
- struct tee_shm *shm, u_int offs)
+ struct tee_shm *shm, u_int offs,
+ bool system_thread)
{
struct optee *optee = tee_get_drvdata(ctx->teedev);
struct optee_call_waiter w;
@@ -957,7 +958,7 @@ static int simple_call_with_arg(struct tee_context *ctx, u32 cmd)
return PTR_ERR(msg_arg);
msg_arg->cmd = cmd;
- optee_smc_do_call_with_arg(ctx, shm, offs);
+ optee_smc_do_call_with_arg(ctx, shm, offs, false);
optee_free_msg_arg(ctx, entry, offs);
return 0;
--
2.25.1
Changes SCMI optee transport to call tee_client_system_session()
to request optee driver to provision an entry context in OP-TEE
for processing OP-TEE messages. This prevents possible deadlock
in case OP-TEE threads are all consumed while these may be waiting
for a clock or regulator to be enable which SCMI OP-TEE service which
requires a free thread context to execute.
Signed-off-by: Etienne Carriere <[email protected]>
---
Changes since v4:
- Updated to new API function tee_client_system_session() introduced
in patch v5 2/3.
No change since v3
Changes since v2:
- Fixed syntax issues (missing ';' chars), reported by kernel test robot.
Changes since v1:
- Updated to use new tee API functions tee_client_request_system_context()
and tee_client_release_system_context().
---
drivers/firmware/arm_scmi/optee.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index 2a7aeab40e54..22a755160c2f 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -440,6 +440,10 @@ static int scmi_optee_chan_setup(struct scmi_chan_info *cinfo, struct device *de
if (ret)
goto err_free_shm;
+ ret = tee_client_system_session(scmi_optee_private->tee_ctx, channel->tee_session);
+ if (ret)
+ dev_warn(dev, "Could not switch to system session, do best effort\n");
+
ret = get_channel(channel);
if (ret)
goto err_close_sess;
--
2.25.1
From: Jens Wiklander <[email protected]>
Adds support in the OP-TEE driver to keep track of reserved system
threads. The optee_cq_*() functions are updated to handle this if
enabled. The SMC ABI part of the driver enables this tracking, but the
FF-A ABI part does not.
Signed-off-by: Jens Wiklander <[email protected]>
Signed-off-by: Etienne Carriere <[email protected]>
---
Changes since v4:
- New change that supersedes implementation proposed in PATCH v4
(tee: system invocation"). Thanks to Jens implementation we don't need
the new OP-TEE services that my previous patch versions introduced to
monitor system threads entry. Now, Linux optee SMC ABI driver gets TEE
provisioned thread contexts count once and monitors thread entries in
OP-TEE on that basis and the system thread capability of the related
tee session. By the way, I dropped the WARN_ONCE() call I suggested
on tee thread exhaustion as it does not provides useful information.
---
drivers/tee/optee/call.c | 128 +++++++++++++++++++++++++++---
drivers/tee/optee/ffa_abi.c | 10 +--
drivers/tee/optee/optee_private.h | 13 ++-
drivers/tee/optee/smc_abi.c | 24 ++++--
4 files changed, 154 insertions(+), 21 deletions(-)
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
index 844d2bdc68db..8b8181099da7 100644
--- a/drivers/tee/optee/call.c
+++ b/drivers/tee/optee/call.c
@@ -39,9 +39,26 @@ struct optee_shm_arg_entry {
DECLARE_BITMAP(map, MAX_ARG_COUNT_PER_ENTRY);
};
+void optee_cq_init(struct optee_call_queue *cq, int thread_count)
+{
+ mutex_init(&cq->mutex);
+ INIT_LIST_HEAD(&cq->normal_waiters);
+ INIT_LIST_HEAD(&cq->sys_waiters);
+ /*
+ * If cq->total_thread_count is 0 then we're not trying to keep
+ * track of how many free threads we have, instead we're relying on
+ * the secure world to tell us when we're out of thread and have to
+ * wait for another thread to become available.
+ */
+ cq->total_thread_count = thread_count;
+ cq->free_normal_thread_count = thread_count;
+}
+
void optee_cq_wait_init(struct optee_call_queue *cq,
- struct optee_call_waiter *w)
+ struct optee_call_waiter *w, bool sys_thread)
{
+ bool need_wait = false;
+
/*
* We're preparing to make a call to secure world. In case we can't
* allocate a thread in secure world we'll end up waiting in
@@ -53,15 +70,40 @@ void optee_cq_wait_init(struct optee_call_queue *cq,
mutex_lock(&cq->mutex);
/*
- * We add ourselves to the queue, but we don't wait. This
- * guarantees that we don't lose a completion if secure world
- * returns busy and another thread just exited and try to complete
- * someone.
+ * We add ourselves to a queue, but we don't wait. This guarantees
+ * that we don't lose a completion if secure world returns busy and
+ * another thread just exited and try to complete someone.
*/
init_completion(&w->c);
- list_add_tail(&w->list_node, &cq->waiters);
+ w->sys_thread = sys_thread;
+ if (sys_thread) {
+ list_add_tail(&w->list_node, &cq->sys_waiters);
+ } else {
+ list_add_tail(&w->list_node, &cq->normal_waiters);
+ if (cq->total_thread_count) {
+ /*
+ * Claim a normal thread if one is available, else
+ * we'll need to wait for a normal thread to be
+ * released.
+ */
+ if (cq->free_normal_thread_count > 0)
+ cq->free_normal_thread_count--;
+ else
+ need_wait = true;
+ }
+ }
mutex_unlock(&cq->mutex);
+
+ while (need_wait) {
+ optee_cq_wait_for_completion(cq, w);
+ mutex_lock(&cq->mutex);
+ if (cq->free_normal_thread_count > 0) {
+ cq->free_normal_thread_count--;
+ need_wait = false;
+ }
+ mutex_unlock(&cq->mutex);
+ }
}
void optee_cq_wait_for_completion(struct optee_call_queue *cq,
@@ -74,7 +116,10 @@ void optee_cq_wait_for_completion(struct optee_call_queue *cq,
/* Move to end of list to get out of the way for other waiters */
list_del(&w->list_node);
reinit_completion(&w->c);
- list_add_tail(&w->list_node, &cq->waiters);
+ if (w->sys_thread)
+ list_add_tail(&w->list_node, &cq->sys_waiters);
+ else
+ list_add_tail(&w->list_node, &cq->normal_waiters);
mutex_unlock(&cq->mutex);
}
@@ -83,10 +128,19 @@ static void optee_cq_complete_one(struct optee_call_queue *cq)
{
struct optee_call_waiter *w;
- list_for_each_entry(w, &cq->waiters, list_node) {
+ list_for_each_entry(w, &cq->sys_waiters, list_node) {
if (!completion_done(&w->c)) {
complete(&w->c);
- break;
+ return;
+ }
+ }
+
+ if (!cq->total_thread_count || cq->free_normal_thread_count > 0) {
+ list_for_each_entry(w, &cq->normal_waiters, list_node) {
+ if (!completion_done(&w->c)) {
+ complete(&w->c);
+ break;
+ }
}
}
}
@@ -104,6 +158,9 @@ void optee_cq_wait_final(struct optee_call_queue *cq,
/* Get out of the list */
list_del(&w->list_node);
+ if (!w->sys_thread)
+ cq->free_normal_thread_count++; /* Release a normal thread */
+
/* Wake up one eventual waiting task */
optee_cq_complete_one(cq);
@@ -119,6 +176,36 @@ void optee_cq_wait_final(struct optee_call_queue *cq,
mutex_unlock(&cq->mutex);
}
+bool optee_cq_inc_sys_thread_count(struct optee_call_queue *cq)
+{
+ bool rc = false;
+
+ mutex_lock(&cq->mutex);
+
+ /* Leave at least 1 normal (non-system) thread */
+ if (cq->res_sys_thread_count + 1 < cq->total_thread_count) {
+ cq->free_normal_thread_count--;
+ cq->res_sys_thread_count++;
+ rc = true;
+ }
+
+ mutex_unlock(&cq->mutex);
+
+ return rc;
+}
+
+void optee_cq_dec_sys_thread_count(struct optee_call_queue *cq)
+{
+ mutex_lock(&cq->mutex);
+ if (cq->res_sys_thread_count > 0) {
+ cq->res_sys_thread_count--;
+ cq->free_normal_thread_count++;
+ /* If there's someone waiting, let it resume */
+ optee_cq_complete_one(cq);
+ }
+ mutex_unlock(&cq->mutex);
+}
+
/* Requires the filpstate mutex to be held */
static struct optee_session *find_session(struct optee_context_data *ctxdata,
u32 session_id)
@@ -361,6 +448,27 @@ int optee_open_session(struct tee_context *ctx,
return rc;
}
+int optee_system_session(struct tee_context *ctx, u32 session)
+{
+ struct optee_context_data *ctxdata = ctx->data;
+ struct optee *optee = tee_get_drvdata(ctx->teedev);
+ struct optee_session *sess;
+ int rc = -EINVAL;
+
+ mutex_lock(&ctxdata->mutex);
+
+ sess = find_session(ctxdata, session);
+ if (sess && !sess->use_sys_thread &&
+ optee_cq_inc_sys_thread_count(&optee->call_queue)) {
+ rc = 0;
+ sess->use_sys_thread = true;
+ }
+
+ mutex_unlock(&ctxdata->mutex);
+
+ return rc;
+}
+
int optee_close_session_helper(struct tee_context *ctx, u32 session,
bool system_thread)
{
@@ -378,6 +486,8 @@ int optee_close_session_helper(struct tee_context *ctx, u32 session,
msg_arg->session = session;
optee->ops->do_call_with_arg(ctx, shm, offs, system_thread);
+ if (system_thread)
+ optee_cq_dec_sys_thread_count(&optee->call_queue);
optee_free_msg_arg(ctx, entry, offs);
return 0;
diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
index 52cec9d06041..0c9055691343 100644
--- a/drivers/tee/optee/ffa_abi.c
+++ b/drivers/tee/optee/ffa_abi.c
@@ -528,7 +528,8 @@ static void optee_handle_ffa_rpc(struct tee_context *ctx, struct optee *optee,
static int optee_ffa_yielding_call(struct tee_context *ctx,
struct ffa_send_direct_data *data,
- struct optee_msg_arg *rpc_arg)
+ struct optee_msg_arg *rpc_arg,
+ bool system_thread)
{
struct optee *optee = tee_get_drvdata(ctx->teedev);
struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
@@ -541,7 +542,7 @@ static int optee_ffa_yielding_call(struct tee_context *ctx,
int rc;
/* Initialize waiter */
- optee_cq_wait_init(&optee->call_queue, &w);
+ optee_cq_wait_init(&optee->call_queue, &w, system_thread);
while (true) {
rc = msg_ops->sync_send_receive(ffa_dev, data);
if (rc)
@@ -643,7 +644,7 @@ static int optee_ffa_do_call_with_arg(struct tee_context *ctx,
if (IS_ERR(rpc_arg))
return PTR_ERR(rpc_arg);
- return optee_ffa_yielding_call(ctx, &data, rpc_arg);
+ return optee_ffa_yielding_call(ctx, &data, rpc_arg, system_thread);
}
/*
@@ -851,8 +852,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
if (rc)
goto err_unreg_supp_teedev;
mutex_init(&optee->ffa.mutex);
- mutex_init(&optee->call_queue.mutex);
- INIT_LIST_HEAD(&optee->call_queue.waiters);
+ optee_cq_init(&optee->call_queue, 0);
optee_supp_init(&optee->supp);
optee_shm_arg_cache_init(optee, arg_cache_flags);
ffa_dev_set_drvdata(ffa_dev, optee);
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index bdbc0dc293bb..4f4201c812e3 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -43,12 +43,17 @@ typedef void (optee_invoke_fn)(unsigned long, unsigned long, unsigned long,
struct optee_call_waiter {
struct list_head list_node;
struct completion c;
+ bool sys_thread;
};
struct optee_call_queue {
/* Serializes access to this struct */
struct mutex mutex;
- struct list_head waiters;
+ struct list_head normal_waiters;
+ struct list_head sys_waiters;
+ int total_thread_count;
+ int free_normal_thread_count;
+ int res_sys_thread_count;
};
struct optee_notif {
@@ -230,6 +235,7 @@ int optee_supp_send(struct tee_context *ctx, u32 ret, u32 num_params,
int optee_open_session(struct tee_context *ctx,
struct tee_ioctl_open_session_arg *arg,
struct tee_param *param);
+int optee_system_session(struct tee_context *ctx, u32 session);
int optee_close_session_helper(struct tee_context *ctx, u32 session,
bool system_thread);
int optee_close_session(struct tee_context *ctx, u32 session);
@@ -279,8 +285,11 @@ static inline void optee_to_msg_param_value(struct optee_msg_param *mp,
mp->u.value.c = p->u.value.c;
}
+void optee_cq_init(struct optee_call_queue *cq, int thread_count);
+bool optee_cq_inc_sys_thread_count(struct optee_call_queue *cq);
+void optee_cq_dec_sys_thread_count(struct optee_call_queue *cq);
void optee_cq_wait_init(struct optee_call_queue *cq,
- struct optee_call_waiter *w);
+ struct optee_call_waiter *w, bool sys_thread);
void optee_cq_wait_for_completion(struct optee_call_queue *cq,
struct optee_call_waiter *w);
void optee_cq_wait_final(struct optee_call_queue *cq,
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index df77700804e5..418c967b83f0 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -261,9 +261,10 @@ static int optee_to_msg_param(struct optee *optee,
static void optee_enable_shm_cache(struct optee *optee)
{
struct optee_call_waiter w;
+ bool system_thread = false;
/* We need to retry until secure world isn't busy. */
- optee_cq_wait_init(&optee->call_queue, &w);
+ optee_cq_wait_init(&optee->call_queue, &w, system_thread);
while (true) {
struct arm_smccc_res res;
@@ -286,9 +287,10 @@ static void optee_enable_shm_cache(struct optee *optee)
static void __optee_disable_shm_cache(struct optee *optee, bool is_mapped)
{
struct optee_call_waiter w;
+ bool system_thread = false;
/* We need to retry until secure world isn't busy. */
- optee_cq_wait_init(&optee->call_queue, &w);
+ optee_cq_wait_init(&optee->call_queue, &w, system_thread);
while (true) {
union {
struct arm_smccc_res smccc;
@@ -907,7 +909,7 @@ static int optee_smc_do_call_with_arg(struct tee_context *ctx,
reg_pair_from_64(¶m.a1, ¶m.a2, parg);
}
/* Initialize waiter */
- optee_cq_wait_init(&optee->call_queue, &w);
+ optee_cq_wait_init(&optee->call_queue, &w, system_thread);
while (true) {
struct arm_smccc_res res;
@@ -1092,6 +1094,7 @@ static const struct tee_driver_ops optee_clnt_ops = {
.release = optee_release,
.open_session = optee_open_session,
.close_session = optee_close_session,
+ .system_session = optee_system_session,
.invoke_func = optee_invoke_func,
.cancel_req = optee_cancel_req,
.shm_register = optee_shm_register,
@@ -1223,6 +1226,16 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
return true;
}
+static unsigned int optee_msg_get_thread_count(optee_invoke_fn *invoke_fn)
+{
+ struct arm_smccc_res res;
+
+ invoke_fn(OPTEE_SMC_GET_THREAD_COUNT, 0, 0, 0, 0, 0, 0, 0, &res);
+ if (res.a0)
+ return 0;
+ return res.a1;
+}
+
static struct tee_shm_pool *
optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
{
@@ -1362,6 +1375,7 @@ static int optee_probe(struct platform_device *pdev)
struct optee *optee = NULL;
void *memremaped_shm = NULL;
unsigned int rpc_param_count;
+ unsigned int thread_count;
struct tee_device *teedev;
struct tee_context *ctx;
u32 max_notif_value;
@@ -1385,6 +1399,7 @@ static int optee_probe(struct platform_device *pdev)
return -EINVAL;
}
+ thread_count = optee_msg_get_thread_count(invoke_fn);
if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps,
&max_notif_value,
&rpc_param_count)) {
@@ -1474,8 +1489,7 @@ static int optee_probe(struct platform_device *pdev)
if (rc)
goto err_unreg_supp_teedev;
- mutex_init(&optee->call_queue.mutex);
- INIT_LIST_HEAD(&optee->call_queue.waiters);
+ optee_cq_init(&optee->call_queue, thread_count);
optee_supp_init(&optee->supp);
optee->smc.memremaped_shm = memremaped_shm;
optee->pool = pool;
--
2.25.1
Adds kernel client API function tee_client_system_session() for a client
to request a system service entry in TEE context.
This feature is needed to prevent a system deadlock when several TEE
client applications invoke TEE, consuming all TEE thread contexts
available in the secure world. The deadlock can happen in the OP-TEE
driver for example if all these TEE threads issue an RPC call from TEE
to Linux OS to access an eMMC RPMB partition (TEE secure storage) which
device clock or regulator controller is accessed through an OP-TEE SCMI
services. In that case, Linux SCMI driver must reach OP-TEE SCMI service
without waiting one of the consumed TEE thread is freed.
Co-developed-by: Jens Wiklander <[email protected]>
Signed-off-by: Jens Wiklander <[email protected]>
Signed-off-by: Etienne Carriere <[email protected]>
---
Changes since v4:
- Changes extracted from "[PATCH v4 1/2] tee: system invocation" and
revised with Jens contribution to cover only definition of tee driver
new API function tee_client_system_session() for kernel clients to
register their session as a system session.
- Commit message rephrased, including header line changed from
"tee: system invocation" to "tee: system session" has the feature
relates to system attributes of tee sessions.
Changes since v3:
- Fixed new SMC funcIDs to reserved/unreserve OP-TEE thread contexts:
minor renaming + define as fastcall funcIDs.
- Moved system_ctx_count from generic struct tee_context to optee's
private struct optee_context_data. This changes optee smc_abi.c
to release reserved thread contexts when the optee device is released.
- Fixed inline description comments.
No change since v2
Change since v1
- Addressed comment on Linux client to claim reservation on TEE context.
This brings 2 new operations from client to TEE to request and release
system thread contexts: 2 new tee_drv.h API functions, 2 new ops
functions in struct tee_driver_ops. The OP-TEE implement shall implement
2 new fastcall SMC funcIDs.
- Fixed typos in commit message.
---
drivers/tee/tee_core.c | 8 ++++++++
include/linux/tee_drv.h | 16 ++++++++++++++++
2 files changed, 24 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 98da206cd761..cf241bf1c6f7 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -1170,6 +1170,14 @@ int tee_client_close_session(struct tee_context *ctx, u32 session)
}
EXPORT_SYMBOL_GPL(tee_client_close_session);
+int tee_client_system_session(struct tee_context *ctx, u32 session)
+{
+ if (!ctx->teedev->desc->ops->system_session)
+ return -EINVAL;
+ return ctx->teedev->desc->ops->system_session(ctx, session);
+}
+EXPORT_SYMBOL_GPL(tee_client_system_session);
+
int tee_client_invoke_func(struct tee_context *ctx,
struct tee_ioctl_invoke_arg *arg,
struct tee_param *param)
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 17eb1c5205d3..911ddf92dcee 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -84,6 +84,7 @@ struct tee_param {
* @release: release this open file
* @open_session: open a new session
* @close_session: close a session
+ * @system_session: declare session as a system session
* @invoke_func: invoke a trusted function
* @cancel_req: request cancel of an ongoing invoke or open
* @supp_recv: called for supplicant to get a command
@@ -100,6 +101,7 @@ struct tee_driver_ops {
struct tee_ioctl_open_session_arg *arg,
struct tee_param *param);
int (*close_session)(struct tee_context *ctx, u32 session);
+ int (*system_session)(struct tee_context *ctx, u32 session);
int (*invoke_func)(struct tee_context *ctx,
struct tee_ioctl_invoke_arg *arg,
struct tee_param *param);
@@ -429,6 +431,20 @@ int tee_client_open_session(struct tee_context *ctx,
*/
int tee_client_close_session(struct tee_context *ctx, u32 session);
+/**
+ * tee_client_system_session() - Declare session as a system session
+ * @ctx: TEE Context
+ * @session: Session id
+ *
+ * This function requests TEE to provision an entry context ready to use for
+ * that session only. The provisioned entry context is used for command
+ * invocation and session closure, not for command cancelling requests.
+ * TEE releases the provisioned context upon session closure.
+ *
+ * Return < 0 on error else 0 if an entry context has been provisioned.
+ */
+int tee_client_system_session(struct tee_context *ctx, u32 session);
+
/**
* tee_client_invoke_func() - Invoke a function in a Trusted Application
* @ctx: TEE Context
--
2.25.1
On Mon, Mar 20, 2023 at 05:28:01PM +0100, Etienne Carriere wrote:
> Changes SCMI optee transport to call tee_client_system_session()
> to request optee driver to provision an entry context in OP-TEE
> for processing OP-TEE messages. This prevents possible deadlock
> in case OP-TEE threads are all consumed while these may be waiting
> for a clock or regulator to be enable which SCMI OP-TEE service which
> requires a free thread context to execute.
>
Assuming it will be routed via OPTEE tree,
Acked-by: Sudeep Holla <[email protected]>
--
Regards,
Sudeep