misc: mic: Add support for kernel mode SCIF clients

Add support for registration/de-registration of kernel mode SCIF
clients. SCIF clients are probed with new and existing SCIF peer
devices. Similarly the client remove method is called when SCIF
peer devices are removed.

Changes to SCIF peer device framework necessitated by supporting
kernel mode SCIF clients are also included in this patch.

Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 19 insertions, 69 deletions

diff --git a/drivers/misc/mic/scif/scif_main.c b/drivers/misc/mic/scif/scif_main.c
index 6ce851f5c7e6..f90bd06900cb 100644
--- a/drivers/misc/mic/scif/scif_main.c
+++ b/drivers/misc/mic/scif/scif_main.c
@@ -80,35 +80,6 @@ irqreturn_t scif_intr_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-static int scif_peer_probe(struct scif_peer_dev *spdev)
-{
-	struct scif_dev *scifdev = &scif_dev[spdev->dnode];
-
-	mutex_lock(&scif_info.conflock);
-	scif_info.total++;
-	scif_info.maxid = max_t(u32, spdev->dnode, scif_info.maxid);
-	mutex_unlock(&scif_info.conflock);
-	rcu_assign_pointer(scifdev->spdev, spdev);
-
-	/* In the future SCIF kernel client devices will be added here */
-	return 0;
-}
-
-static void scif_peer_remove(struct scif_peer_dev *spdev)
-{
-	struct scif_dev *scifdev = &scif_dev[spdev->dnode];
-
-	/* In the future SCIF kernel client devices will be removed here */
-	spdev = rcu_dereference(scifdev->spdev);
-	if (spdev)
-		RCU_INIT_POINTER(scifdev->spdev, NULL);
-	synchronize_rcu();
-
-	mutex_lock(&scif_info.conflock);
-	scif_info.total--;
-	mutex_unlock(&scif_info.conflock);
-}
-
 static void scif_qp_setup_handler(struct work_struct *work)
 {
 	struct scif_dev *scifdev = container_of(work, struct scif_dev,
@@ -139,20 +110,13 @@ static void scif_qp_setup_handler(struct work_struct *work)
 	}
 }
 
-static int scif_setup_scifdev(struct scif_hw_dev *sdev)
+static int scif_setup_scifdev(void)
 {
+	/* We support a maximum of 129 SCIF nodes including the mgmt node */
+#define MAX_SCIF_NODES 129
 	int i;
-	u8 num_nodes;
+	u8 num_nodes = MAX_SCIF_NODES;
 
-	if (sdev->snode) {
-		struct mic_bootparam __iomem *bp = sdev->rdp;
-
-		num_nodes = ioread8(&bp->tot_nodes);
-	} else {
-		struct mic_bootparam *bp = sdev->dp;
-
-		num_nodes = bp->tot_nodes;
-	}
 	scif_dev = kcalloc(num_nodes, sizeof(*scif_dev), GFP_KERNEL);
 	if (!scif_dev)
 		return -ENOMEM;
@@ -163,7 +127,7 @@ static int scif_setup_scifdev(struct scif_hw_dev *sdev)
 		scifdev->exit = OP_IDLE;
 		init_waitqueue_head(&scifdev->disconn_wq);
 		mutex_init(&scifdev->lock);
-		INIT_WORK(&scifdev->init_msg_work, scif_qp_response_ack);
+		INIT_WORK(&scifdev->peer_add_work, scif_add_peer_device);
 		INIT_DELAYED_WORK(&scifdev->p2p_dwork,
 				  scif_poll_qp_state);
 		INIT_DELAYED_WORK(&scifdev->qp_dwork,
@@ -181,27 +145,21 @@ static void scif_destroy_scifdev(void)
 
 static int scif_probe(struct scif_hw_dev *sdev)
 {
-	struct scif_dev *scifdev;
+	struct scif_dev *scifdev = &scif_dev[sdev->dnode];
 	int rc;
 
 	dev_set_drvdata(&sdev->dev, sdev);
+	scifdev->sdev = sdev;
+
 	if (1 == atomic_add_return(1, &g_loopb_cnt)) {
-		struct scif_dev *loopb_dev;
+		struct scif_dev *loopb_dev = &scif_dev[sdev->snode];
 
-		rc = scif_setup_scifdev(sdev);
-		if (rc)
-			goto exit;
-		scifdev = &scif_dev[sdev->dnode];
-		scifdev->sdev = sdev;
-		loopb_dev = &scif_dev[sdev->snode];
 		loopb_dev->sdev = sdev;
 		rc = scif_setup_loopback_qp(loopb_dev);
 		if (rc)
-			goto free_sdev;
-	} else {
-		scifdev = &scif_dev[sdev->dnode];
-		scifdev->sdev = sdev;
+			goto exit;
 	}
+
 	rc = scif_setup_intr_wq(scifdev);
 	if (rc)
 		goto destroy_loopb;
@@ -237,8 +195,6 @@ destroy_intr:
 destroy_loopb:
 	if (atomic_dec_and_test(&g_loopb_cnt))
 		scif_destroy_loopback_qp(&scif_dev[sdev->snode]);
-free_sdev:
-	scif_destroy_scifdev();
 exit:
 	return rc;
 }
@@ -290,13 +246,6 @@ static void scif_remove(struct scif_hw_dev *sdev)
 	scifdev->sdev = NULL;
 }
 
-static struct scif_peer_driver scif_peer_driver = {
-	.driver.name =	KBUILD_MODNAME,
-	.driver.owner =	THIS_MODULE,
-	.probe = scif_peer_probe,
-	.remove = scif_peer_remove,
-};
-
 static struct scif_hw_dev_id id_table[] = {
 	{ MIC_SCIF_DEV, SCIF_DEV_ANY_ID },
 	{ 0 },
@@ -312,6 +261,8 @@ static struct scif_driver scif_driver = {
 
 static int _scif_init(void)
 {
+	int rc;
+
 	spin_lock_init(&scif_info.eplock);
 	spin_lock_init(&scif_info.nb_connect_lock);
 	spin_lock_init(&scif_info.port_lock);
@@ -326,10 +277,15 @@ static int _scif_init(void)
 	init_waitqueue_head(&scif_info.exitwq);
 	scif_info.en_msg_log = 0;
 	scif_info.p2p_enable = 1;
+	rc = scif_setup_scifdev();
+	if (rc)
+		goto error;
 	INIT_WORK(&scif_info.misc_work, scif_misc_handler);
 	INIT_WORK(&scif_info.conn_work, scif_conn_handler);
 	idr_init(&scif_ports);
 	return 0;
+error:
+	return rc;
 }
 
 static void _scif_exit(void)
@@ -347,12 +303,9 @@ static int __init scif_init(void)
 	rc = scif_peer_bus_init();
 	if (rc)
 		goto exit;
-	rc = scif_peer_register_driver(&scif_peer_driver);
-	if (rc)
-		goto peer_bus_exit;
 	rc = scif_register_driver(&scif_driver);
 	if (rc)
-		goto unreg_scif_peer;
+		goto peer_bus_exit;
 	rc = misc_register(mdev);
 	if (rc)
 		goto unreg_scif;
@@ -360,8 +313,6 @@ static int __init scif_init(void)
 	return 0;
 unreg_scif:
 	scif_unregister_driver(&scif_driver);
-unreg_scif_peer:
-	scif_peer_unregister_driver(&scif_peer_driver);
 peer_bus_exit:
 	scif_peer_bus_exit();
 exit:
@@ -374,7 +325,6 @@ static void __exit scif_exit(void)
 	scif_exit_debugfs();
 	misc_deregister(&scif_info.mdev);
 	scif_unregister_driver(&scif_driver);
-	scif_peer_unregister_driver(&scif_peer_driver);
 	scif_peer_bus_exit();
 	_scif_exit();
 }