1 files changed, 0 insertions, 399 deletions
diff --git a/drivers/misc/mic/cosm/cosm_scif_server.c b/drivers/misc/mic/cosm/cosm_scif_server.c
deleted file mode 100644
index 7baec9fd8756..000000000000
--- a/drivers/misc/mic/cosm/cosm_scif_server.c
+++ /dev/null
@@ -1,399 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Intel MIC Platform Software Stack (MPSS)
- *
- * Copyright(c) 2015 Intel Corporation.
- *
- * Intel MIC Coprocessor State Management (COSM) Driver
- */
-#include <linux/kthread.h>
-#include <linux/sched/signal.h>
-
-#include "cosm_main.h"
-
-/*
- * The COSM driver uses SCIF to communicate between the management node and the
- * MIC cards. SCIF is used to (a) Send a shutdown command to the card (b)
- * receive a shutdown status back from the card upon completion of shutdown and
- * (c) receive periodic heartbeat messages from the card used to deduce if the
- * card has crashed.
- *
- * A COSM server consisting of a SCIF listening endpoint waits for incoming
- * connections from the card. Upon acceptance of the connection, a separate
- * work-item is scheduled to handle SCIF message processing for that card. The
- * life-time of this work-item is therefore the time from which the connection
- * from a card is accepted to the time at which the connection is closed. A new
- * work-item starts each time the card boots and is alive till the card (a)
- * shuts down (b) is reset (c) crashes (d) cosm_client driver on the card is
- * unloaded.
- *
- * From the point of view of COSM interactions with SCIF during card
- * shutdown, reset and crash are as follows:
- *
- * Card shutdown
- * -------------
- * 1. COSM client on the card invokes orderly_poweroff() in response to SHUTDOWN
- *    message from the host.
- * 2. Card driver shutdown callback invokes scif_unregister_device(..) resulting
- *    in scif_remove(..) getting called on the card
- * 3. scif_remove -> scif_stop -> scif_handle_remove_node ->
- *    scif_peer_unregister_device -> device_unregister for the host peer device
- * 4. During device_unregister remove(..) method of cosm_client is invoked which
- *    closes the COSM SCIF endpoint on the card. This results in a SCIF_DISCNCT
- *    message being sent to host SCIF. SCIF_DISCNCT message processing on the
- *    host SCIF sets the host COSM SCIF endpoint state to DISCONNECTED and wakes
- *    up the host COSM thread blocked in scif_poll(..) resulting in
- *    scif_poll(..)  returning EPOLLHUP.
- * 5. On the card, scif_peer_release_dev is next called which results in an
- *    SCIF_EXIT message being sent to the host and after receiving the
- *    SCIF_EXIT_ACK from the host the peer device teardown on the card is
- *    complete.
- * 6. As part of the SCIF_EXIT message processing on the host, host sends a
- *    SCIF_REMOVE_NODE to itself corresponding to the card being removed. This
- *    starts a similar SCIF peer device teardown sequence on the host
- *    corresponding to the card being shut down.
- *
- * Card reset
- * ----------
- * The case of interest here is when the card has not been previously shut down
- * since most of the steps below are skipped in that case:
-
- * 1. cosm_stop(..) invokes hw_ops->stop(..) method of the base PCIe driver
- *    which unregisters the SCIF HW device resulting in scif_remove(..) being
- *    called on the host.
- * 2. scif_remove(..) calls scif_disconnect_node(..) which results in a
- *    SCIF_EXIT message being sent to the card.
- * 3. The card executes scif_stop() as part of SCIF_EXIT message
- *    processing. This results in the COSM endpoint on the card being closed and
- *    the SCIF host peer device on the card getting unregistered similar to
- *    steps 3, 4 and 5 for the card shutdown case above. scif_poll(..) on the
- *    host returns EPOLLHUP as a result.
- * 4. On the host, card peer device unregister and SCIF HW remove(..) also
- *    subsequently complete.
- *
- * Card crash
- * ----------
- * If a reset is issued after the card has crashed, there is no SCIF_DISCNT
- * message from the card which would result in scif_poll(..) returning
- * EPOLLHUP. In this case when the host SCIF driver sends a SCIF_REMOVE_NODE
- * message to itself resulting in the card SCIF peer device being unregistered,
- * this results in a scif_peer_release_dev -> scif_cleanup_scifdev->
- * scif_invalidate_ep call sequence which sets the endpoint state to
- * DISCONNECTED and results in scif_poll(..) returning EPOLLHUP.
- */
-
-#define COSM_SCIF_BACKLOG 16
-#define COSM_HEARTBEAT_CHECK_DELTA_SEC 10
-#define COSM_HEARTBEAT_TIMEOUT_SEC \
-		(COSM_HEARTBEAT_SEND_SEC + COSM_HEARTBEAT_CHECK_DELTA_SEC)
-#define COSM_HEARTBEAT_TIMEOUT_MSEC (COSM_HEARTBEAT_TIMEOUT_SEC * MSEC_PER_SEC)
-
-static struct task_struct *server_thread;
-static scif_epd_t listen_epd;
-
-/* Publish MIC card's shutdown status to user space MIC daemon */
-static void cosm_update_mic_status(struct cosm_device *cdev)
-{
-	if (cdev->shutdown_status_int != MIC_NOP) {
-		cosm_set_shutdown_status(cdev, cdev->shutdown_status_int);
-		cdev->shutdown_status_int = MIC_NOP;
-	}
-}
-
-/* Store MIC card's shutdown status internally when it is received */
-static void cosm_shutdown_status_int(struct cosm_device *cdev,
-				     enum mic_status shutdown_status)
-{
-	switch (shutdown_status) {
-	case MIC_HALTED:
-	case MIC_POWER_OFF:
-	case MIC_RESTART:
-	case MIC_CRASHED:
-		break;
-	default:
-		dev_err(&cdev->dev, "%s %d Unexpected shutdown_status %d\n",
-			__func__, __LINE__, shutdown_status);
-		return;
-	};
-	cdev->shutdown_status_int = shutdown_status;
-	cdev->heartbeat_watchdog_enable = false;
-
-	if (cdev->state != MIC_SHUTTING_DOWN)
-		cosm_set_state(cdev, MIC_SHUTTING_DOWN);
-}
-
-/* Non-blocking recv. Read and process all available messages */
-static void cosm_scif_recv(struct cosm_device *cdev)
-{
-	struct cosm_msg msg;
-	int rc;
-
-	while (1) {
-		rc = scif_recv(cdev->epd, &msg, sizeof(msg), 0);
-		if (!rc) {
-			break;
-		} else if (rc < 0) {
-			dev_dbg(&cdev->dev, "%s: %d rc %d\n",
-				__func__, __LINE__, rc);
-			break;
-		}
-		dev_dbg(&cdev->dev, "%s: %d rc %d id 0x%llx\n",
-			__func__, __LINE__, rc, msg.id);
-
-		switch (msg.id) {
-		case COSM_MSG_SHUTDOWN_STATUS:
-			cosm_shutdown_status_int(cdev, msg.shutdown_status);
-			break;
-		case COSM_MSG_HEARTBEAT:
-			/* Nothing to do, heartbeat only unblocks scif_poll */
-			break;
-		default:
-			dev_err(&cdev->dev, "%s: %d unknown msg.id %lld\n",
-				__func__, __LINE__, msg.id);
-			break;
-		}
-	}
-}
-
-/* Publish crashed status for this MIC card */
-static void cosm_set_crashed(struct cosm_device *cdev)
-{
-	dev_err(&cdev->dev, "node alive timeout\n");
-	cosm_shutdown_status_int(cdev, MIC_CRASHED);
-	cosm_update_mic_status(cdev);
-}
-
-/* Send host time to the MIC card to sync system time between host and MIC */
-static void cosm_send_time(struct cosm_device *cdev)
-{
-	struct cosm_msg msg = { .id = COSM_MSG_SYNC_TIME };
-	struct timespec64 ts;
-	int rc;
-
-	ktime_get_real_ts64(&ts);
-	msg.timespec.tv_sec = ts.tv_sec;
-	msg.timespec.tv_nsec = ts.tv_nsec;
-
-	rc = scif_send(cdev->epd, &msg, sizeof(msg), SCIF_SEND_BLOCK);
-	if (rc < 0)
-		dev_err(&cdev->dev, "%s %d scif_send failed rc %d\n",
-			__func__, __LINE__, rc);
-}
-
-/*
- * Close this cosm_device's endpoint after its peer endpoint on the card has
- * been closed. In all cases except MIC card crash EPOLLHUP on the host is
- * triggered by the client's endpoint being closed.
- */
-static void cosm_scif_close(struct cosm_device *cdev)
-{
-	/*
-	 * Because SHUTDOWN_STATUS message is sent by the MIC cards in the
-	 * reboot notifier when shutdown is still not complete, we notify mpssd
-	 * to reset the card when SCIF endpoint is closed.
-	 */
-	cosm_update_mic_status(cdev);
-	scif_close(cdev->epd);
-	cdev->epd = NULL;
-	dev_dbg(&cdev->dev, "%s %d\n", __func__, __LINE__);
-}
-
-/*
- * Set card state to ONLINE when a new SCIF connection from a MIC card is
- * received. Normally the state is BOOTING when the connection comes in, but can
- * be ONLINE if cosm_client driver on the card was unloaded and then reloaded.
- */
-static int cosm_set_online(struct cosm_device *cdev)
-{
-	int rc = 0;
-
-	if (MIC_BOOTING == cdev->state || MIC_ONLINE == cdev->state) {
-		cdev->heartbeat_watchdog_enable = cdev->sysfs_heartbeat_enable;
-		cdev->epd = cdev->newepd;
-		if (cdev->state == MIC_BOOTING)
-			cosm_set_state(cdev, MIC_ONLINE);
-		cosm_send_time(cdev);
-		dev_dbg(&cdev->dev, "%s %d\n", __func__, __LINE__);
-	} else {
-		dev_warn(&cdev->dev, "%s %d not going online in state: %s\n",
-			 __func__, __LINE__, cosm_state_string[cdev->state]);
-		rc = -EINVAL;
-	}
-	/* Drop reference acquired by bus_find_device in the server thread */
-	put_device(&cdev->dev);
-	return rc;
-}
-
-/*
- * Work function for handling work for a SCIF connection from a particular MIC
- * card. It first sets the card state to ONLINE and then calls scif_poll to
- * block on activity such as incoming messages on the SCIF endpoint. When the
- * endpoint is closed, the work function exits, completing its life cycle, from
- * MIC card boot to card shutdown/reset/crash.
- */
-void cosm_scif_work(struct work_struct *work)
-{
-	struct cosm_device *cdev = container_of(work, struct cosm_device,
-						scif_work);
-	struct scif_pollepd pollepd;
-	int rc;
-
-	mutex_lock(&cdev->cosm_mutex);
-	if (cosm_set_online(cdev))
-		goto exit;
-
-	while (1) {
-		pollepd.epd = cdev->epd;
-		pollepd.events = EPOLLIN;
-
-		/* Drop the mutex before blocking in scif_poll(..) */
-		mutex_unlock(&cdev->cosm_mutex);
-		/* poll(..) with timeout on our endpoint */
-		rc = scif_poll(&pollepd, 1, COSM_HEARTBEAT_TIMEOUT_MSEC);
-		mutex_lock(&cdev->cosm_mutex);
-		if (rc < 0) {
-			dev_err(&cdev->dev, "%s %d scif_poll rc %d\n",
-				__func__, __LINE__, rc);
-			continue;
-		}
-
-		/* There is a message from the card */
-		if (pollepd.revents & EPOLLIN)
-			cosm_scif_recv(cdev);
-
-		/* The peer endpoint is closed or this endpoint disconnected */
-		if (pollepd.revents & EPOLLHUP) {
-			cosm_scif_close(cdev);
-			break;
-		}
-
-		/* Did we timeout from poll? */
-		if (!rc && cdev->heartbeat_watchdog_enable)
-			cosm_set_crashed(cdev);
-	}
-exit:
-	dev_dbg(&cdev->dev, "%s %d exiting\n", __func__, __LINE__);
-	mutex_unlock(&cdev->cosm_mutex);
-}
-
-/*
- * COSM SCIF server thread function. Accepts incoming SCIF connections from MIC
- * cards, finds the correct cosm_device to associate that connection with and
- * schedules individual work items for each MIC card.
- */
-static int cosm_scif_server(void *unused)
-{
-	struct cosm_device *cdev;
-	scif_epd_t newepd;
-	struct scif_port_id port_id;
-	int rc;
-
-	allow_signal(SIGKILL);
-
-	while (!kthread_should_stop()) {
-		rc = scif_accept(listen_epd, &port_id, &newepd,
-				 SCIF_ACCEPT_SYNC);
-		if (rc < 0) {
-			if (-ERESTARTSYS != rc)
-				pr_err("%s %d rc %d\n", __func__, __LINE__, rc);
-			continue;
-		}
-
-		/*
-		 * Associate the incoming connection with a particular
-		 * cosm_device, COSM device ID == SCIF node ID - 1
-		 */
-		cdev = cosm_find_cdev_by_id(port_id.node - 1);
-		if (!cdev)
-			continue;
-		cdev->newepd = newepd;
-		schedule_work(&cdev->scif_work);
-	}
-
-	pr_debug("%s %d Server thread stopped\n", __func__, __LINE__);
-	return 0;
-}
-
-static int cosm_scif_listen(void)
-{
-	int rc;
-
-	listen_epd = scif_open();
-	if (!listen_epd) {
-		pr_err("%s %d scif_open failed\n", __func__, __LINE__);
-		return -ENOMEM;
-	}
-
-	rc = scif_bind(listen_epd, SCIF_COSM_LISTEN_PORT);
-	if (rc < 0) {
-		pr_err("%s %d scif_bind failed rc %d\n",
-		       __func__, __LINE__, rc);
-		goto err;
-	}
-
-	rc = scif_listen(listen_epd, COSM_SCIF_BACKLOG);
-	if (rc < 0) {
-		pr_err("%s %d scif_listen rc %d\n", __func__, __LINE__, rc);
-		goto err;
-	}
-	pr_debug("%s %d listen_epd set up\n", __func__, __LINE__);
-	return 0;
-err:
-	scif_close(listen_epd);
-	listen_epd = NULL;
-	return rc;
-}
-
-static void cosm_scif_listen_exit(void)
-{
-	pr_debug("%s %d closing listen_epd\n", __func__, __LINE__);
-	if (listen_epd) {
-		scif_close(listen_epd);
-		listen_epd = NULL;
-	}
-}
-
-/*
- * Create a listening SCIF endpoint and a server kthread which accepts incoming
- * SCIF connections from MIC cards
- */
-int cosm_scif_init(void)
-{
-	int rc = cosm_scif_listen();
-
-	if (rc) {
-		pr_err("%s %d cosm_scif_listen rc %d\n",
-		       __func__, __LINE__, rc);
-		goto err;
-	}
-
-	server_thread = kthread_run(cosm_scif_server, NULL, "cosm_server");
-	if (IS_ERR(server_thread)) {
-		rc = PTR_ERR(server_thread);
-		pr_err("%s %d kthread_run rc %d\n", __func__, __LINE__, rc);
-		goto listen_exit;
-	}
-	return 0;
-listen_exit:
-	cosm_scif_listen_exit();
-err:
-	return rc;
-}
-
-/* Stop the running server thread and close the listening SCIF endpoint */
-void cosm_scif_exit(void)
-{
-	int rc;
-
-	if (!IS_ERR_OR_NULL(server_thread)) {
-		rc = send_sig(SIGKILL, server_thread, 0);
-		if (rc) {
-			pr_err("%s %d send_sig rc %d\n",
-			       __func__, __LINE__, rc);
-			return;
-		}
-		kthread_stop(server_thread);
-	}
-
-	cosm_scif_listen_exit();
-}