misc: mic: SCIF node queue pair setup management

/*

 * 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 "scif_peer_bus.h"

#include "scif_main.h"

#include "scif_map.h"

void scif_free_qp(struct scif_dev *scifdev)

{

	struct scif_qp *qp = scifdev->qpairs;

	if (!qp)

		return;

	scif_free_coherent((void *)qp->inbound_q.rb_base,

			   qp->local_buf, scifdev, qp->inbound_q.size);

	scif_unmap_single(qp->local_qp, scifdev, sizeof(struct scif_qp));

	kfree(scifdev->qpairs);

	scifdev->qpairs = NULL;

}

static void scif_cleanup_qp(struct scif_dev *dev)

{

	struct scif_qp *qp = &dev->qpairs[0];

	if (!qp)

		return;

	scif_iounmap((void *)qp->remote_qp, sizeof(struct scif_qp), dev);

	scif_iounmap((void *)qp->outbound_q.rb_base,

		     sizeof(struct scif_qp), dev);

	qp->remote_qp = NULL;

	qp->local_write = 0;

	qp->inbound_q.current_write_offset = 0;

	qp->inbound_q.current_read_offset = 0;

	if (scifdev_is_p2p(dev))

		scif_free_qp(dev);

}

void scif_send_acks(struct scif_dev *dev)

{

	struct scifmsg msg;

	if (dev->node_remove_ack_pending) {

		msg.uop = SCIF_NODE_REMOVE_ACK;

		msg.src.node = scif_info.nodeid;

		msg.dst.node = SCIF_MGMT_NODE;

		msg.payload[0] = dev->node;

		scif_nodeqp_send(&scif_dev[SCIF_MGMT_NODE], &msg);

		dev->node_remove_ack_pending = false;

	}

	if (dev->exit_ack_pending) {

		msg.uop = SCIF_EXIT_ACK;

		msg.src.node = scif_info.nodeid;

		msg.dst.node = dev->node;

		scif_nodeqp_send(dev, &msg);

		dev->exit_ack_pending = false;

	}

}

/*

 * scif_cleanup_scifdev

 *

 * @dev: Remote SCIF device.

 * Uninitialize SCIF data structures for remote SCIF device.

 */

void scif_cleanup_scifdev(struct scif_dev *dev)

{

	struct scif_hw_dev *sdev = dev->sdev;

	if (!dev->sdev)

		return;

	if (scifdev_is_p2p(dev)) {

		if (dev->cookie) {

			sdev->hw_ops->free_irq(sdev, dev->cookie, dev);

			dev->cookie = NULL;

		}

		scif_destroy_intr_wq(dev);

	}

	scif_destroy_p2p(dev);

	scif_send_acks(dev);

	if (!dev->node && scif_info.card_initiated_exit) {

		/*

		 * Send an SCIF_EXIT message which is the last message from MIC

		 * to the Host and wait for a SCIF_EXIT_ACK

		 */

		scif_send_exit(dev);

		scif_info.card_initiated_exit = false;

	}

	scif_cleanup_qp(dev);

}

/*

 * scif_remove_node:

 *

 * @node: Node to remove

 */

void scif_handle_remove_node(int node)

{

	struct scif_dev *scifdev = &scif_dev[node];

	struct scif_peer_dev *spdev;

	rcu_read_lock();

	spdev = rcu_dereference(scifdev->spdev);

	rcu_read_unlock();

	if (spdev)

		scif_peer_unregister_device(spdev);

	else

		scif_send_acks(scifdev);

}

static int scif_send_rmnode_msg(int node, int remove_node)

{

	struct scifmsg notif_msg;

	struct scif_dev *dev = &scif_dev[node];

	notif_msg.uop = SCIF_NODE_REMOVE;

	notif_msg.src.node = scif_info.nodeid;

	notif_msg.dst.node = node;

	notif_msg.payload[0] = remove_node;

	return scif_nodeqp_send(dev, &notif_msg);

}

/**

 * scif_node_disconnect:

 *

 * @node_id[in]: source node id.

 * @mgmt_initiated: Disconnection initiated from the mgmt node

 *

 * Disconnect a node from the scif network.

 */

void scif_disconnect_node(u32 node_id, bool mgmt_initiated)

{

	int ret;

	int msg_cnt = 0;

	u32 i = 0;

	struct scif_dev *scifdev = &scif_dev[node_id];

	if (!node_id)

		return;

	atomic_set(&scifdev->disconn_rescnt, 0);

	/* Destroy p2p network */

	for (i = 1; i <= scif_info.maxid; i++) {

		if (i == node_id)

			continue;

		ret = scif_send_rmnode_msg(i, node_id);

		if (!ret)

			msg_cnt++;

	}

	/* Wait for the remote nodes to respond with SCIF_NODE_REMOVE_ACK */

	ret = wait_event_timeout(scifdev->disconn_wq,

				 (atomic_read(&scifdev->disconn_rescnt)

				 == msg_cnt), SCIF_NODE_ALIVE_TIMEOUT);

	/* Tell the card to clean up */

	if (mgmt_initiated && _scifdev_alive(scifdev))

		/*

		 * Send an SCIF_EXIT message which is the last message from Host

		 * to the MIC and wait for a SCIF_EXIT_ACK

		 */

		scif_send_exit(scifdev);

	atomic_set(&scifdev->disconn_rescnt, 0);

	/* Tell the mgmt node to clean up */

	ret = scif_send_rmnode_msg(SCIF_MGMT_NODE, node_id);

	if (!ret)

		/* Wait for mgmt node to respond with SCIF_NODE_REMOVE_ACK */

		wait_event_timeout(scifdev->disconn_wq,

				   (atomic_read(&scifdev->disconn_rescnt) == 1),

				   SCIF_NODE_ALIVE_TIMEOUT);

}