SPM: Prevent simultaneous blocking calls
Blocking calls can only succeed if the target Secure Partition is idle.
Change-Id: Iabeaa0b8d3e653fd8581fa086758936abfc1c772
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/services/std_svc/spm/spm_main.c b/services/std_svc/spm/spm_main.c
index b1d5dd8..050c66c 100644
--- a/services/std_svc/spm/spm_main.c
+++ b/services/std_svc/spm/spm_main.c
@@ -47,6 +47,39 @@
}
/*******************************************************************************
+ * Functions to keep track of how many requests a Secure Partition has received
+ * and hasn't finished.
+ ******************************************************************************/
+void spm_sp_request_increase(sp_context_t *sp_ctx)
+{
+ spin_lock(&(sp_ctx->request_count_lock));
+ sp_ctx->request_count++;
+ spin_unlock(&(sp_ctx->request_count_lock));
+}
+
+void spm_sp_request_decrease(sp_context_t *sp_ctx)
+{
+ spin_lock(&(sp_ctx->request_count_lock));
+ sp_ctx->request_count--;
+ spin_unlock(&(sp_ctx->request_count_lock));
+}
+
+/* Returns 0 if it was originally 0, -1 otherwise. */
+int spm_sp_request_increase_if_zero(sp_context_t *sp_ctx)
+{
+ int ret = -1;
+
+ spin_lock(&(sp_ctx->request_count_lock));
+ if (sp_ctx->request_count == 0U) {
+ sp_ctx->request_count++;
+ ret = 0U;
+ }
+ spin_unlock(&(sp_ctx->request_count_lock));
+
+ return ret;
+}
+
+/*******************************************************************************
* This function returns a pointer to the context of the Secure Partition that
* handles the service specified by an UUID. It returns NULL if the UUID wasn't
* found.