Use ids for identifying messages sent to EthosU firmware

Avoid to use pointers to kernel memory as identify messages, prior this
change, if memory is reused that can lead to unexpected conflicts.

Remove ref counting from capabilities and network_info since memory is
freed in only one place.

Finally, extract the capabilities code in its own files.

Change-Id: I9ab7257f3ab85fa3347be65b3739e0daf9b5a441

1 files changed, 40 insertions, 23 deletions

diff --git a/kernel/ethosu_mailbox.c b/kernel/ethosu_mailbox.c
index 843cb58..014ceb8 100644
--- a/kernel/ethosu_mailbox.c
+++ b/kernel/ethosu_mailbox.c
@@ -282,34 +282,51 @@ int ethosu_mailbox_read(struct ethosu_mailbox *mbox,
 	return 0;
 }
 
-int ethosu_mailbox_find(struct ethosu_mailbox *mbox,
-			struct ethosu_mailbox_msg *msg)
+int ethosu_mailbox_register(struct ethosu_mailbox *mbox,
+			    struct ethosu_mailbox_msg *msg)
 {
-	struct ethosu_mailbox_msg *cur;
+	msg->id = idr_alloc_cyclic(&mbox->msg_idr, msg, 0, INT_MAX, GFP_KERNEL);
+	if (msg->id < 0)
+		return msg->id;
 
-	list_for_each_entry(cur, &mbox->pending_list, list) {
-		if (cur == msg)
-			return 0;
-	}
+	return 0;
+}
+
+void ethosu_mailbox_deregister(struct ethosu_mailbox *mbox,
+			       struct ethosu_mailbox_msg *msg)
+{
+	idr_remove(&mbox->msg_idr, msg->id);
+}
+
+struct ethosu_mailbox_msg *ethosu_mailbox_find(struct ethosu_mailbox *mbox,
+					       int msg_id)
+{
+	struct ethosu_mailbox_msg *ptr = (struct ethosu_mailbox_msg *)idr_find(
+		&mbox->msg_idr, msg_id);
 
-	return -EINVAL;
+	if (ptr == NULL)
+		return ERR_PTR(-EINVAL);
+
+	return ptr;
 }
 
 void ethosu_mailbox_fail(struct ethosu_mailbox *mbox)
 {
-	struct ethosu_mailbox_msg *cur, *cur_tmp;
+	struct ethosu_mailbox_msg *cur;
+	int id;
 
-	list_for_each_entry_safe(cur, cur_tmp, &mbox->pending_list, list) {
+	idr_for_each_entry(&mbox->msg_idr, cur, id) {
 		cur->fail(cur);
 	}
 }
 
 void ethosu_mailbox_resend(struct ethosu_mailbox *mbox)
 {
-	struct ethosu_mailbox_msg *cur, *cur_tmp;
+	struct ethosu_mailbox_msg *cur;
+	int id;
 	int ret;
 
-	list_for_each_entry_safe(cur, cur_tmp, &mbox->pending_list, list) {
+	idr_for_each_entry(&mbox->msg_idr, cur, id) {
 		ret = cur->resend(cur);
 		if (ret) {
 			dev_warn(mbox->dev, "Failed to resend msg. ret=%d",
@@ -336,10 +353,10 @@ int ethosu_mailbox_version_request(struct ethosu_mailbox *mbox)
 }
 
 int ethosu_mailbox_capabilities_request(struct ethosu_mailbox *mbox,
-					void *user_arg)
+					struct ethosu_mailbox_msg *msg)
 {
 	struct ethosu_core_capabilities_req req = {
-		.user_arg = (ptrdiff_t)user_arg
+		.user_arg = msg->id
 	};
 
 	return ethosu_queue_write_msg(mbox, ETHOSU_CORE_MSG_CAPABILITIES_REQ,
@@ -348,7 +365,7 @@ int ethosu_mailbox_capabilities_request(struct ethosu_mailbox *mbox,
 }
 
 int ethosu_mailbox_inference(struct ethosu_mailbox *mbox,
-			     void *user_arg,
+			     struct ethosu_mailbox_msg *msg,
 			     uint32_t ifm_count,
 			     struct ethosu_buffer **ifm,
 			     uint32_t ofm_count,
@@ -369,7 +386,7 @@ int ethosu_mailbox_inference(struct ethosu_mailbox *mbox,
 		return -EINVAL;
 	}
 
-	inf.user_arg = (ptrdiff_t)user_arg;
+	inf.user_arg = msg->id;
 	inf.ifm_count = ifm_count;
 	inf.ofm_count = ofm_count;
 	inf.pmu_cycle_counter_enable = pmu_cycle_counter_enable;
@@ -396,13 +413,13 @@ int ethosu_mailbox_inference(struct ethosu_mailbox *mbox,
 }
 
 int ethosu_mailbox_network_info_request(struct ethosu_mailbox *mbox,
-					void *user_arg,
+					struct ethosu_mailbox_msg *msg,
 					struct ethosu_buffer *network,
 					uint32_t network_index)
 {
 	struct ethosu_core_network_info_req info;
 
-	info.user_arg = (ptrdiff_t)user_arg;
+	info.user_arg = msg->id;
 
 	if (network != NULL) {
 		info.network.type = ETHOSU_CORE_NETWORK_BUFFER;
@@ -417,13 +434,13 @@ int ethosu_mailbox_network_info_request(struct ethosu_mailbox *mbox,
 }
 
 int ethosu_mailbox_cancel_inference(struct ethosu_mailbox *mbox,
-				    void *user_arg,
-				    void *inference_handle)
+				    struct ethosu_mailbox_msg *msg,
+				    int inference_handle)
 {
 	struct ethosu_core_cancel_inference_req req;
 
-	req.user_arg = (ptrdiff_t)user_arg;
-	req.inference_handle = (ptrdiff_t)inference_handle;
+	req.user_arg = msg->id;
+	req.inference_handle = inference_handle;
 
 	return ethosu_queue_write_msg(mbox,
 				      ETHOSU_CORE_MSG_CANCEL_INFERENCE_REQ,
@@ -473,7 +490,7 @@ int ethosu_mailbox_init(struct ethosu_mailbox *mbox,
 	mbox->user_arg = user_arg;
 	mbox->wdog = wdog;
 	mbox->ping_count = 0;
-	INIT_LIST_HEAD(&mbox->pending_list);
+	idr_init(&mbox->msg_idr);
 
 	mbox->client.dev = dev;
 	mbox->client.rx_callback = ethosu_mailbox_rx_callback;