optee: separate notification functions

Renames struct optee_wait_queue to struct optee_notif and all related
functions to optee_notif_*().

The implementation is changed to allow sending a notification from an
atomic state, that is from the top half of an interrupt handler.

Waiting for keys is currently only used when secure world is waiting for
a mutex or condition variable. The old implementation could handle any
32-bit key while this new implementation is restricted to only 8 bits or
the maximum value 255. A upper value is needed since a bitmap is
allocated to allow an interrupt handler to only set a bit in case the
waiter hasn't had the time yet to allocate and register a completion.

The keys are currently only representing secure world threads which
number usually are never even close to 255 so it should be safe for now.
In future ABI updates the maximum value of the key will be communicated
while the driver is initializing.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

1 files changed, 7 insertions, 64 deletions

diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
index cd642e340eaf..e69bc6380683 100644
--- a/drivers/tee/optee/rpc.c
+++ b/drivers/tee/optee/rpc.c
@@ -12,23 +12,6 @@
 #include "optee_private.h"
 #include "optee_rpc_cmd.h"
 
-struct wq_entry {
-	struct list_head link;
-	struct completion c;
-	u32 key;
-};
-
-void optee_wait_queue_init(struct optee_wait_queue *priv)
-{
-	mutex_init(&priv->mu);
-	INIT_LIST_HEAD(&priv->db);
-}
-
-void optee_wait_queue_exit(struct optee_wait_queue *priv)
-{
-	mutex_destroy(&priv->mu);
-}
-
 static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg)
 {
 	struct timespec64 ts;
@@ -144,48 +127,6 @@ static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
 }
 #endif
 
-static struct wq_entry *wq_entry_get(struct optee_wait_queue *wq, u32 key)
-{
-	struct wq_entry *w;
-
-	mutex_lock(&wq->mu);
-
-	list_for_each_entry(w, &wq->db, link)
-		if (w->key == key)
-			goto out;
-
-	w = kmalloc(sizeof(*w), GFP_KERNEL);
-	if (w) {
-		init_completion(&w->c);
-		w->key = key;
-		list_add_tail(&w->link, &wq->db);
-	}
-out:
-	mutex_unlock(&wq->mu);
-	return w;
-}
-
-static void wq_sleep(struct optee_wait_queue *wq, u32 key)
-{
-	struct wq_entry *w = wq_entry_get(wq, key);
-
-	if (w) {
-		wait_for_completion(&w->c);
-		mutex_lock(&wq->mu);
-		list_del(&w->link);
-		mutex_unlock(&wq->mu);
-		kfree(w);
-	}
-}
-
-static void wq_wakeup(struct optee_wait_queue *wq, u32 key)
-{
-	struct wq_entry *w = wq_entry_get(wq, key);
-
-	if (w)
-		complete(&w->c);
-}
-
 static void handle_rpc_func_cmd_wq(struct optee *optee,
 				   struct optee_msg_arg *arg)
 {
@@ -197,11 +138,13 @@ static void handle_rpc_func_cmd_wq(struct optee *optee,
 		goto bad;
 
 	switch (arg->params[0].u.value.a) {
-	case OPTEE_RPC_WAIT_QUEUE_SLEEP:
-		wq_sleep(&optee->wait_queue, arg->params[0].u.value.b);
+	case OPTEE_RPC_NOTIFICATION_WAIT:
+		if (optee_notif_wait(optee, arg->params[0].u.value.b))
+			goto bad;
 		break;
-	case OPTEE_RPC_WAIT_QUEUE_WAKEUP:
-		wq_wakeup(&optee->wait_queue, arg->params[0].u.value.b);
+	case OPTEE_RPC_NOTIFICATION_SEND:
+		if (optee_notif_send(optee, arg->params[0].u.value.b))
+			goto bad;
 		break;
 	default:
 		goto bad;
@@ -319,7 +262,7 @@ void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee,
 	case OPTEE_RPC_CMD_GET_TIME:
 		handle_rpc_func_cmd_get_time(arg);
 		break;
-	case OPTEE_RPC_CMD_WAIT_QUEUE:
+	case OPTEE_RPC_CMD_NOTIFICATION:
 		handle_rpc_func_cmd_wq(optee, arg);
 		break;
 	case OPTEE_RPC_CMD_SUSPEND: