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path: root/drivers/misc/mic/scif/scif_ports.c
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Diffstat (limited to 'drivers/misc/mic/scif/scif_ports.c')
-rw-r--r--drivers/misc/mic/scif/scif_ports.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_ports.c b/drivers/misc/mic/scif/scif_ports.c
new file mode 100644
index 000000000000..594e18d279d8
--- /dev/null
+++ b/drivers/misc/mic/scif/scif_ports.c
@@ -0,0 +1,124 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * Intel SCIF driver.
+ *
+ */
+#include <linux/idr.h>
+
+#include "scif_main.h"
+
+#define SCIF_PORT_COUNT	0x10000	/* Ports available */
+
+struct idr scif_ports;
+
+/*
+ * struct scif_port - SCIF port information
+ *
+ * @ref_cnt - Reference count since there can be multiple endpoints
+ *		created via scif_accept(..) simultaneously using a port.
+ */
+struct scif_port {
+	int ref_cnt;
+};
+
+/**
+ * __scif_get_port - Reserve a specified port # for SCIF and add it
+ * to the global list.
+ * @port : port # to be reserved.
+ *
+ * @return : Allocated SCIF port #, or -ENOSPC if port unavailable.
+ *		On memory allocation failure, returns -ENOMEM.
+ */
+static int __scif_get_port(int start, int end)
+{
+	int id;
+	struct scif_port *port = kzalloc(sizeof(*port), GFP_ATOMIC);
+
+	if (!port)
+		return -ENOMEM;
+	spin_lock(&scif_info.port_lock);
+	id = idr_alloc(&scif_ports, port, start, end, GFP_ATOMIC);
+	if (id >= 0)
+		port->ref_cnt++;
+	spin_unlock(&scif_info.port_lock);
+	return id;
+}
+
+/**
+ * scif_rsrv_port - Reserve a specified port # for SCIF.
+ * @port : port # to be reserved.
+ *
+ * @return : Allocated SCIF port #, or -ENOSPC if port unavailable.
+ *		On memory allocation failure, returns -ENOMEM.
+ */
+int scif_rsrv_port(u16 port)
+{
+	return __scif_get_port(port, port + 1);
+}
+
+/**
+ * scif_get_new_port - Get and reserve any port # for SCIF in the range
+ *			SCIF_PORT_RSVD + 1 to SCIF_PORT_COUNT - 1.
+ *
+ * @return : Allocated SCIF port #, or -ENOSPC if no ports available.
+ *		On memory allocation failure, returns -ENOMEM.
+ */
+int scif_get_new_port(void)
+{
+	return __scif_get_port(SCIF_PORT_RSVD + 1, SCIF_PORT_COUNT);
+}
+
+/**
+ * scif_get_port - Increment the reference count for a SCIF port
+ * @id : SCIF port
+ *
+ * @return : None
+ */
+void scif_get_port(u16 id)
+{
+	struct scif_port *port;
+
+	if (!id)
+		return;
+	spin_lock(&scif_info.port_lock);
+	port = idr_find(&scif_ports, id);
+	if (port)
+		port->ref_cnt++;
+	spin_unlock(&scif_info.port_lock);
+}
+
+/**
+ * scif_put_port - Release a reserved SCIF port
+ * @id : SCIF port to be released.
+ *
+ * @return : None
+ */
+void scif_put_port(u16 id)
+{
+	struct scif_port *port;
+
+	if (!id)
+		return;
+	spin_lock(&scif_info.port_lock);
+	port = idr_find(&scif_ports, id);
+	if (port) {
+		port->ref_cnt--;
+		if (!port->ref_cnt) {
+			idr_remove(&scif_ports, id);
+			kfree(port);
+		}
+	}
+	spin_unlock(&scif_info.port_lock);
+}