1 files changed, 417 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_api.c b/drivers/misc/mic/scif/scif_api.c
new file mode 100644
index 000000000000..cbdc27b3b187
--- /dev/null
+++ b/drivers/misc/mic/scif/scif_api.c
@@ -0,0 +1,417 @@
+/*
+ * 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/scif.h>
+#include "scif_main.h"
+#include "scif_map.h"
+
+static const char * const scif_ep_states[] = {
+	"Unbound",
+	"Bound",
+	"Listening",
+	"Connected",
+	"Connecting",
+	"Mapping",
+	"Closing",
+	"Close Listening",
+	"Disconnected",
+	"Zombie"};
+
+enum conn_async_state {
+	ASYNC_CONN_IDLE = 1,	/* ep setup for async connect */
+	ASYNC_CONN_INPROGRESS,	/* async connect in progress */
+	ASYNC_CONN_FLUSH_WORK	/* async work flush in progress  */
+};
+
+scif_epd_t scif_open(void)
+{
+	struct scif_endpt *ep;
+
+	might_sleep();
+	ep = kzalloc(sizeof(*ep), GFP_KERNEL);
+	if (!ep)
+		goto err_ep_alloc;
+
+	ep->qp_info.qp = kzalloc(sizeof(*ep->qp_info.qp), GFP_KERNEL);
+	if (!ep->qp_info.qp)
+		goto err_qp_alloc;
+
+	spin_lock_init(&ep->lock);
+	mutex_init(&ep->sendlock);
+	mutex_init(&ep->recvlock);
+
+	ep->state = SCIFEP_UNBOUND;
+	dev_dbg(scif_info.mdev.this_device,
+		"SCIFAPI open: ep %p success\n", ep);
+	return ep;
+
+err_qp_alloc:
+	kfree(ep);
+err_ep_alloc:
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(scif_open);
+
+/*
+ * scif_disconnect_ep - Disconnects the endpoint if found
+ * @epd: The end point returned from scif_open()
+ */
+static struct scif_endpt *scif_disconnect_ep(struct scif_endpt *ep)
+{
+	struct scifmsg msg;
+	struct scif_endpt *fep = NULL;
+	struct scif_endpt *tmpep;
+	struct list_head *pos, *tmpq;
+	int err;
+
+	/*
+	 * Wake up any threads blocked in send()/recv() before closing
+	 * out the connection. Grabbing and releasing the send/recv lock
+	 * will ensure that any blocked senders/receivers have exited for
+	 * Ring 0 endpoints. It is a Ring 0 bug to call send/recv after
+	 * close. Ring 3 endpoints are not affected since close will not
+	 * be called while there are IOCTLs executing.
+	 */
+	wake_up_interruptible(&ep->sendwq);
+	wake_up_interruptible(&ep->recvwq);
+	mutex_lock(&ep->sendlock);
+	mutex_unlock(&ep->sendlock);
+	mutex_lock(&ep->recvlock);
+	mutex_unlock(&ep->recvlock);
+
+	/* Remove from the connected list */
+	mutex_lock(&scif_info.connlock);
+	list_for_each_safe(pos, tmpq, &scif_info.connected) {
+		tmpep = list_entry(pos, struct scif_endpt, list);
+		if (tmpep == ep) {
+			list_del(pos);
+			fep = tmpep;
+			spin_lock(&ep->lock);
+			break;
+		}
+	}
+
+	if (!fep) {
+		/*
+		 * The other side has completed the disconnect before
+		 * the end point can be removed from the list. Therefore
+		 * the ep lock is not locked, traverse the disconnected
+		 * list to find the endpoint and release the conn lock.
+		 */
+		list_for_each_safe(pos, tmpq, &scif_info.disconnected) {
+			tmpep = list_entry(pos, struct scif_endpt, list);
+			if (tmpep == ep) {
+				list_del(pos);
+				break;
+			}
+		}
+		mutex_unlock(&scif_info.connlock);
+		return NULL;
+	}
+
+	init_completion(&ep->discon);
+	msg.uop = SCIF_DISCNCT;
+	msg.src = ep->port;
+	msg.dst = ep->peer;
+	msg.payload[0] = (u64)ep;
+	msg.payload[1] = ep->remote_ep;
+
+	err = scif_nodeqp_send(ep->remote_dev, &msg);
+	spin_unlock(&ep->lock);
+	mutex_unlock(&scif_info.connlock);
+
+	if (!err)
+		/* Wait for the remote node to respond with SCIF_DISCNT_ACK */
+		wait_for_completion_timeout(&ep->discon,
+					    SCIF_NODE_ALIVE_TIMEOUT);
+	return ep;
+}
+
+int scif_close(scif_epd_t epd)
+{
+	struct scif_endpt *ep = (struct scif_endpt *)epd;
+	struct scif_endpt *tmpep;
+	struct list_head *pos, *tmpq;
+	enum scif_epd_state oldstate;
+	bool flush_conn;
+
+	dev_dbg(scif_info.mdev.this_device, "SCIFAPI close: ep %p %s\n",
+		ep, scif_ep_states[ep->state]);
+	might_sleep();
+	spin_lock(&ep->lock);
+	flush_conn = (ep->conn_async_state == ASYNC_CONN_INPROGRESS);
+	spin_unlock(&ep->lock);
+
+	if (flush_conn)
+		flush_work(&scif_info.conn_work);
+
+	spin_lock(&ep->lock);
+	oldstate = ep->state;
+
+	ep->state = SCIFEP_CLOSING;
+
+	switch (oldstate) {
+	case SCIFEP_ZOMBIE:
+	case SCIFEP_DISCONNECTED:
+		spin_unlock(&ep->lock);
+		/* Remove from the disconnected list */
+		mutex_lock(&scif_info.connlock);
+		list_for_each_safe(pos, tmpq, &scif_info.disconnected) {
+			tmpep = list_entry(pos, struct scif_endpt, list);
+			if (tmpep == ep) {
+				list_del(pos);
+				break;
+			}
+		}
+		mutex_unlock(&scif_info.connlock);
+		break;
+	case SCIFEP_UNBOUND:
+	case SCIFEP_BOUND:
+	case SCIFEP_CONNECTING:
+		spin_unlock(&ep->lock);
+		break;
+	case SCIFEP_MAPPING:
+	case SCIFEP_CONNECTED:
+	case SCIFEP_CLOSING:
+	{
+		spin_unlock(&ep->lock);
+		scif_disconnect_ep(ep);
+		break;
+	}
+	case SCIFEP_LISTENING:
+	case SCIFEP_CLLISTEN:
+	{
+		struct scif_conreq *conreq;
+		struct scifmsg msg;
+		struct scif_endpt *aep;
+
+		spin_unlock(&ep->lock);
+		spin_lock(&scif_info.eplock);
+
+		/* remove from listen list */
+		list_for_each_safe(pos, tmpq, &scif_info.listen) {
+			tmpep = list_entry(pos, struct scif_endpt, list);
+			if (tmpep == ep)
+				list_del(pos);
+		}
+		/* Remove any dangling accepts */
+		while (ep->acceptcnt) {
+			aep = list_first_entry(&ep->li_accept,
+					       struct scif_endpt, liacceptlist);
+			list_del(&aep->liacceptlist);
+			scif_put_port(aep->port.port);
+			list_for_each_safe(pos, tmpq, &scif_info.uaccept) {
+				tmpep = list_entry(pos, struct scif_endpt,
+						   miacceptlist);
+				if (tmpep == aep) {
+					list_del(pos);
+					break;
+				}
+			}
+			spin_unlock(&scif_info.eplock);
+			mutex_lock(&scif_info.connlock);
+			list_for_each_safe(pos, tmpq, &scif_info.connected) {
+				tmpep = list_entry(pos,
+						   struct scif_endpt, list);
+				if (tmpep == aep) {
+					list_del(pos);
+					break;
+				}
+			}
+			list_for_each_safe(pos, tmpq, &scif_info.disconnected) {
+				tmpep = list_entry(pos,
+						   struct scif_endpt, list);
+				if (tmpep == aep) {
+					list_del(pos);
+					break;
+				}
+			}
+			mutex_unlock(&scif_info.connlock);
+			scif_teardown_ep(aep);
+			spin_lock(&scif_info.eplock);
+			scif_add_epd_to_zombie_list(aep, SCIF_EPLOCK_HELD);
+			ep->acceptcnt--;
+		}
+
+		spin_lock(&ep->lock);
+		spin_unlock(&scif_info.eplock);
+
+		/* Remove and reject any pending connection requests. */
+		while (ep->conreqcnt) {
+			conreq = list_first_entry(&ep->conlist,
+						  struct scif_conreq, list);
+			list_del(&conreq->list);
+
+			msg.uop = SCIF_CNCT_REJ;
+			msg.dst.node = conreq->msg.src.node;
+			msg.dst.port = conreq->msg.src.port;
+			msg.payload[0] = conreq->msg.payload[0];
+			msg.payload[1] = conreq->msg.payload[1];
+			/*
+			 * No Error Handling on purpose for scif_nodeqp_send().
+			 * If the remote node is lost we still want free the
+			 * connection requests on the self node.
+			 */
+			scif_nodeqp_send(&scif_dev[conreq->msg.src.node],
+					 &msg);
+			ep->conreqcnt--;
+			kfree(conreq);
+		}
+
+		spin_unlock(&ep->lock);
+		/* If a kSCIF accept is waiting wake it up */
+		wake_up_interruptible(&ep->conwq);
+		break;
+	}
+	}
+	scif_put_port(ep->port.port);
+	scif_teardown_ep(ep);
+	scif_add_epd_to_zombie_list(ep, !SCIF_EPLOCK_HELD);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(scif_close);
+
+/**
+ * scif_flush() - Wakes up any blocking accepts. The endpoint will no longer
+ *			accept new connections.
+ * @epd: The end point returned from scif_open()
+ */
+int __scif_flush(scif_epd_t epd)
+{
+	struct scif_endpt *ep = (struct scif_endpt *)epd;
+
+	switch (ep->state) {
+	case SCIFEP_LISTENING:
+	{
+		ep->state = SCIFEP_CLLISTEN;
+
+		/* If an accept is waiting wake it up */
+		wake_up_interruptible(&ep->conwq);
+		break;
+	}
+	default:
+		break;
+	}
+	return 0;
+}
+
+int scif_bind(scif_epd_t epd, u16 pn)
+{
+	struct scif_endpt *ep = (struct scif_endpt *)epd;
+	int ret = 0;
+	int tmp;
+
+	dev_dbg(scif_info.mdev.this_device,
+		"SCIFAPI bind: ep %p %s requested port number %d\n",
+		ep, scif_ep_states[ep->state], pn);
+	if (pn) {
+		/*
+		 * Similar to IETF RFC 1700, SCIF ports below
+		 * SCIF_ADMIN_PORT_END can only be bound by system (or root)
+		 * processes or by processes executed by privileged users.
+		 */
+		if (pn < SCIF_ADMIN_PORT_END && !capable(CAP_SYS_ADMIN)) {
+			ret = -EACCES;
+			goto scif_bind_admin_exit;
+		}
+	}
+
+	spin_lock(&ep->lock);
+	if (ep->state == SCIFEP_BOUND) {
+		ret = -EINVAL;
+		goto scif_bind_exit;
+	} else if (ep->state != SCIFEP_UNBOUND) {
+		ret = -EISCONN;
+		goto scif_bind_exit;
+	}
+
+	if (pn) {
+		tmp = scif_rsrv_port(pn);
+		if (tmp != pn) {
+			ret = -EINVAL;
+			goto scif_bind_exit;
+		}
+	} else {
+		pn = scif_get_new_port();
+		if (!pn) {
+			ret = -ENOSPC;
+			goto scif_bind_exit;
+		}
+	}
+
+	ep->state = SCIFEP_BOUND;
+	ep->port.node = scif_info.nodeid;
+	ep->port.port = pn;
+	ep->conn_async_state = ASYNC_CONN_IDLE;
+	ret = pn;
+	dev_dbg(scif_info.mdev.this_device,
+		"SCIFAPI bind: bound to port number %d\n", pn);
+scif_bind_exit:
+	spin_unlock(&ep->lock);
+scif_bind_admin_exit:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(scif_bind);
+
+int scif_listen(scif_epd_t epd, int backlog)
+{
+	struct scif_endpt *ep = (struct scif_endpt *)epd;
+
+	dev_dbg(scif_info.mdev.this_device,
+		"SCIFAPI listen: ep %p %s\n", ep, scif_ep_states[ep->state]);
+	spin_lock(&ep->lock);
+	switch (ep->state) {
+	case SCIFEP_ZOMBIE:
+	case SCIFEP_CLOSING:
+	case SCIFEP_CLLISTEN:
+	case SCIFEP_UNBOUND:
+	case SCIFEP_DISCONNECTED:
+		spin_unlock(&ep->lock);
+		return -EINVAL;
+	case SCIFEP_LISTENING:
+	case SCIFEP_CONNECTED:
+	case SCIFEP_CONNECTING:
+	case SCIFEP_MAPPING:
+		spin_unlock(&ep->lock);
+		return -EISCONN;
+	case SCIFEP_BOUND:
+		break;
+	}
+
+	ep->state = SCIFEP_LISTENING;
+	ep->backlog = backlog;
+
+	ep->conreqcnt = 0;
+	ep->acceptcnt = 0;
+	INIT_LIST_HEAD(&ep->conlist);
+	init_waitqueue_head(&ep->conwq);
+	INIT_LIST_HEAD(&ep->li_accept);
+	spin_unlock(&ep->lock);
+
+	/*
+	 * Listen status is complete so delete the qp information not needed
+	 * on a listen before placing on the list of listening ep's
+	 */
+	scif_teardown_ep(ep);
+	ep->qp_info.qp = NULL;
+
+	spin_lock(&scif_info.eplock);
+	list_add_tail(&ep->list, &scif_info.listen);
+	spin_unlock(&scif_info.eplock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(scif_listen);