3 files changed, 338 insertions, 41 deletions

diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c
index 74f06f3c073..2946eee8e70 100644
--- a/drivers/scsi/isci/port.c
+++ b/drivers/scsi/isci/port.c
@@ -152,6 +152,71 @@ static enum sci_status scic_port_get_properties(struct scic_sds_port *port,
 	return SCI_SUCCESS;
 }
 
+static void scic_port_bcn_enable(struct scic_sds_port *sci_port)
+{
+	struct scic_sds_phy *sci_phy;
+	u32 val;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(sci_port->phy_table); i++) {
+		sci_phy = sci_port->phy_table[i];
+		if (!sci_phy)
+			continue;
+		val = readl(&sci_phy->link_layer_registers->link_layer_control);
+		/* clear the bit by writing 1. */
+		writel(val, &sci_phy->link_layer_registers->link_layer_control);
+	}
+}
+
+/* called under scic_lock to stabilize phy:port associations */
+void isci_port_bcn_enable(struct isci_host *ihost, struct isci_port *iport)
+{
+	int i;
+
+	clear_bit(IPORT_BCN_BLOCKED, &iport->flags);
+	wake_up(&ihost->eventq);
+
+	if (!test_and_clear_bit(IPORT_BCN_PENDING, &iport->flags))
+		return;
+
+	for (i = 0; i < ARRAY_SIZE(iport->sci.phy_table); i++) {
+		struct scic_sds_phy *sci_phy = iport->sci.phy_table[i];
+		struct isci_phy *iphy = sci_phy_to_iphy(sci_phy);
+
+		if (!sci_phy)
+			continue;
+
+		ihost->sas_ha.notify_port_event(&iphy->sas_phy,
+						PORTE_BROADCAST_RCVD);
+		break;
+	}
+}
+
+void isci_port_bc_change_received(struct isci_host *ihost,
+				  struct scic_sds_port *sci_port,
+				  struct scic_sds_phy *sci_phy)
+{
+	struct isci_phy *iphy = sci_phy_to_iphy(sci_phy);
+	struct isci_port *iport = iphy->isci_port;
+
+	if (iport && test_bit(IPORT_BCN_BLOCKED, &iport->flags)) {
+		dev_dbg(&ihost->pdev->dev,
+			"%s: disabled BCN; isci_phy = %p, sas_phy = %p\n",
+			__func__, iphy, &iphy->sas_phy);
+		set_bit(IPORT_BCN_PENDING, &iport->flags);
+		atomic_inc(&iport->event);
+		wake_up(&ihost->eventq);
+	} else {
+		dev_dbg(&ihost->pdev->dev,
+			"%s: isci_phy = %p, sas_phy = %p\n",
+			__func__, iphy, &iphy->sas_phy);
+
+		ihost->sas_ha.notify_port_event(&iphy->sas_phy,
+						PORTE_BROADCAST_RCVD);
+	}
+	scic_port_bcn_enable(sci_port);
+}
+
 static void isci_port_link_up(struct isci_host *isci_host,
 			      struct scic_sds_port *port,
 			      struct scic_sds_phy *phy)
@@ -240,13 +305,15 @@ static void isci_port_link_down(struct isci_host *isci_host,
 	if (isci_port) {
 
 		/* check to see if this is the last phy on this port. */
-		if (isci_phy->sas_phy.port
-		    && isci_phy->sas_phy.port->num_phys == 1) {
-
-			/* change the state for all devices on this port.
-			 * The next task sent to this device will be returned
-			 * as SAS_TASK_UNDELIVERED, and the scsi mid layer
-			 * will remove the target
+		if (isci_phy->sas_phy.port &&
+		    isci_phy->sas_phy.port->num_phys == 1) {
+			atomic_inc(&isci_port->event);
+			isci_port_bcn_enable(isci_host, isci_port);
+
+			/* change the state for all devices on this port.  The
+			 * next task sent to this device will be returned as
+			 * SAS_TASK_UNDELIVERED, and the scsi mid layer will
+			 * remove the target
 			 */
 			list_for_each_entry(isci_device,
 					    &isci_port->remote_dev_list,
@@ -1033,26 +1100,6 @@ enum sas_linkrate scic_sds_port_get_max_allowed_speed(
 	return max_allowed_speed;
 }
 
-static void scic_port_enable_broadcast_change_notification(struct scic_sds_port *port)
-{
-	struct scic_sds_phy *phy;
-	u32 register_value;
-	u8 index;
-
-	/* Loop through all of the phys to enable BCN. */
-	for (index = 0; index < SCI_MAX_PHYS; index++) {
-		phy = port->phy_table[index];
-		if (phy != NULL) {
-			register_value =
-				readl(&phy->link_layer_registers->link_layer_control);
-
-			/* clear the bit by writing 1. */
-			writel(register_value,
-				&phy->link_layer_registers->link_layer_control);
-		}
-	}
-}
-
 /**
  *
  * @sci_port: This is the struct scic_sds_port object to suspend.
@@ -1838,6 +1885,7 @@ void isci_port_init(struct isci_port *iport, struct isci_host *ihost, int index)
 	init_completion(&iport->start_complete);
 	iport->isci_host = ihost;
 	isci_port_change_state(iport, isci_freed);
+	atomic_set(&iport->event, 0);
 }
 
 /**
@@ -1852,19 +1900,6 @@ enum isci_status isci_port_get_state(
 	return isci_port->status;
 }
 
-static void isci_port_bc_change_received(struct isci_host *ihost,
-					 struct scic_sds_port *sci_port,
-					 struct scic_sds_phy *sci_phy)
-{
-	struct isci_phy *iphy = sci_phy_to_iphy(sci_phy);
-
-	dev_dbg(&ihost->pdev->dev, "%s: iphy = %p, sas_phy = %p\n",
-		__func__, iphy, &iphy->sas_phy);
-
-	ihost->sas_ha.notify_port_event(&iphy->sas_phy, PORTE_BROADCAST_RCVD);
-	scic_port_enable_broadcast_change_notification(sci_port);
-}
-
 void scic_sds_port_broadcast_change_received(
 	struct scic_sds_port *sci_port,
 	struct scic_sds_phy *sci_phy)
diff --git a/drivers/scsi/isci/port.h b/drivers/scsi/isci/port.h
index fee6d80df76..45c01f80bf8 100644
--- a/drivers/scsi/isci/port.h
+++ b/drivers/scsi/isci/port.h
@@ -173,6 +173,10 @@ struct scic_sds_port {
  */
 struct isci_port {
 	enum isci_status status;
+	#define IPORT_BCN_BLOCKED 0
+	#define IPORT_BCN_PENDING 1
+	unsigned long flags;
+	atomic_t event;
 	struct isci_host *isci_host;
 	struct asd_sas_port sas_port;
 	struct list_head remote_dev_list;
@@ -334,6 +338,7 @@ void scic_sds_port_setup_transports(
 	struct scic_sds_port *sci_port,
 	u32 device_id);
 
+void isci_port_bcn_enable(struct isci_host *, struct isci_port *);
 
 void scic_sds_port_deactivate_phy(
 	struct scic_sds_port *sci_port,
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 69f17b98e4f..709c0817174 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -56,6 +56,7 @@
 #include <linux/completion.h>
 #include <linux/irqflags.h>
 #include "sas.h"
+#include <scsi/libsas.h>
 #include "remote_device.h"
 #include "remote_node_context.h"
 #include "isci.h"
@@ -1397,11 +1398,250 @@ isci_task_request_complete(struct isci_host *ihost,
 	complete(tmf_complete);
 }
 
+static void isci_smp_task_timedout(unsigned long _task)
+{
+	struct sas_task *task = (void *) _task;
+	unsigned long flags;
+
+	spin_lock_irqsave(&task->task_state_lock, flags);
+	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
+		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
+	spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+	complete(&task->completion);
+}
+
+static void isci_smp_task_done(struct sas_task *task)
+{
+	if (!del_timer(&task->timer))
+		return;
+	complete(&task->completion);
+}
+
+static struct sas_task *isci_alloc_task(void)
+{
+	struct sas_task *task = kzalloc(sizeof(*task), GFP_KERNEL);
+
+	if (task) {
+		INIT_LIST_HEAD(&task->list);
+		spin_lock_init(&task->task_state_lock);
+		task->task_state_flags = SAS_TASK_STATE_PENDING;
+		init_timer(&task->timer);
+		init_completion(&task->completion);
+	}
+
+	return task;
+}
+
+static void isci_free_task(struct isci_host *ihost, struct sas_task  *task)
+{
+	if (task) {
+		BUG_ON(!list_empty(&task->list));
+		kfree(task);
+	}
+}
+
+static int isci_smp_execute_task(struct isci_host *ihost,
+				 struct domain_device *dev, void *req,
+				 int req_size, void *resp, int resp_size)
+{
+	int res, retry;
+	struct sas_task *task = NULL;
+
+	for (retry = 0; retry < 3; retry++) {
+		task = isci_alloc_task();
+		if (!task)
+			return -ENOMEM;
+
+		task->dev = dev;
+		task->task_proto = dev->tproto;
+		sg_init_one(&task->smp_task.smp_req, req, req_size);
+		sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
+
+		task->task_done = isci_smp_task_done;
+
+		task->timer.data = (unsigned long) task;
+		task->timer.function = isci_smp_task_timedout;
+		task->timer.expires = jiffies + 10*HZ;
+		add_timer(&task->timer);
+
+		res = isci_task_execute_task(task, 1, GFP_KERNEL);
+
+		if (res) {
+			del_timer(&task->timer);
+			dev_err(&ihost->pdev->dev,
+				"%s: executing SMP task failed:%d\n",
+				__func__, res);
+			goto ex_err;
+		}
+
+		wait_for_completion(&task->completion);
+		res = -ECOMM;
+		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
+			dev_err(&ihost->pdev->dev,
+				"%s: smp task timed out or aborted\n",
+				__func__);
+			isci_task_abort_task(task);
+			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
+				dev_err(&ihost->pdev->dev,
+					"%s: SMP task aborted and not done\n",
+					__func__);
+				goto ex_err;
+			}
+		}
+		if (task->task_status.resp == SAS_TASK_COMPLETE &&
+		    task->task_status.stat == SAM_STAT_GOOD) {
+			res = 0;
+			break;
+		}
+		if (task->task_status.resp == SAS_TASK_COMPLETE &&
+		      task->task_status.stat == SAS_DATA_UNDERRUN) {
+			/* no error, but return the number of bytes of
+			* underrun */
+			res = task->task_status.residual;
+			break;
+		}
+		if (task->task_status.resp == SAS_TASK_COMPLETE &&
+		      task->task_status.stat == SAS_DATA_OVERRUN) {
+			res = -EMSGSIZE;
+			break;
+		} else {
+			dev_err(&ihost->pdev->dev,
+				"%s: task to dev %016llx response: 0x%x "
+				"status 0x%x\n", __func__,
+				SAS_ADDR(dev->sas_addr),
+				task->task_status.resp,
+				task->task_status.stat);
+			isci_free_task(ihost, task);
+			task = NULL;
+		}
+	}
+ex_err:
+	BUG_ON(retry == 3 && task != NULL);
+	isci_free_task(ihost, task);
+	return res;
+}
+
+#define DISCOVER_REQ_SIZE  16
+#define DISCOVER_RESP_SIZE 56
+
+int isci_smp_get_phy_attached_dev_type(struct isci_host *ihost,
+				       struct domain_device *dev,
+				       int phy_id, int *adt)
+{
+	struct smp_resp *disc_resp;
+	u8 *disc_req;
+	int res;
+
+	disc_resp = kzalloc(DISCOVER_RESP_SIZE, GFP_KERNEL);
+	if (!disc_resp)
+		return -ENOMEM;
+
+	disc_req = kzalloc(DISCOVER_REQ_SIZE, GFP_KERNEL);
+	if (disc_req) {
+		disc_req[0] = SMP_REQUEST;
+		disc_req[1] = SMP_DISCOVER;
+		disc_req[9] = phy_id;
+	} else {
+		kfree(disc_resp);
+		return -ENOMEM;
+	}
+	res = isci_smp_execute_task(ihost, dev, disc_req, DISCOVER_REQ_SIZE,
+				    disc_resp, DISCOVER_RESP_SIZE);
+	if (!res) {
+		if (disc_resp->result != SMP_RESP_FUNC_ACC)
+			res = disc_resp->result;
+		else
+			*adt = disc_resp->disc.attached_dev_type;
+	}
+	kfree(disc_req);
+	kfree(disc_resp);
+
+	return res;
+}
+
+static void isci_wait_for_smp_phy_reset(struct isci_remote_device *idev, int phy_num)
+{
+	struct domain_device *dev = idev->domain_dev;
+	struct isci_port *iport = idev->isci_port;
+	struct isci_host *ihost = iport->isci_host;
+	int res, iteration = 0, attached_device_type;
+	#define STP_WAIT_MSECS 25000
+	unsigned long tmo = msecs_to_jiffies(STP_WAIT_MSECS);
+	unsigned long deadline = jiffies + tmo;
+	enum {
+		SMP_PHYWAIT_PHYDOWN,
+		SMP_PHYWAIT_PHYUP,
+		SMP_PHYWAIT_DONE
+	} phy_state = SMP_PHYWAIT_PHYDOWN;
+
+	/* While there is time, wait for the phy to go away and come back */
+	while (time_is_after_jiffies(deadline) && phy_state != SMP_PHYWAIT_DONE) {
+		int event = atomic_read(&iport->event);
+
+		++iteration;
+
+		tmo = wait_event_timeout(ihost->eventq,
+					 event != atomic_read(&iport->event) ||
+					 !test_bit(IPORT_BCN_BLOCKED, &iport->flags),
+					 tmo);
+		/* link down, stop polling */
+		if (!test_bit(IPORT_BCN_BLOCKED, &iport->flags))
+			break;
+
+		dev_dbg(&ihost->pdev->dev,
+			"%s: iport %p, iteration %d,"
+			" phase %d: time_remaining %lu, bcns = %d\n",
+			__func__, iport, iteration, phy_state,
+			tmo, test_bit(IPORT_BCN_PENDING, &iport->flags));
+
+		res = isci_smp_get_phy_attached_dev_type(ihost, dev, phy_num,
+							 &attached_device_type);
+		tmo = deadline - jiffies;
+
+		if (res) {
+			dev_warn(&ihost->pdev->dev,
+				 "%s: iteration %d, phase %d:"
+				 " SMP error=%d, time_remaining=%lu\n",
+				 __func__, iteration, phy_state, res, tmo);
+			break;
+		}
+		dev_dbg(&ihost->pdev->dev,
+			"%s: iport %p, iteration %d,"
+			" phase %d: time_remaining %lu, bcns = %d, "
+			"attdevtype = %x\n",
+			__func__, iport, iteration, phy_state,
+			tmo, test_bit(IPORT_BCN_PENDING, &iport->flags),
+			attached_device_type);
+
+		switch (phy_state) {
+		case SMP_PHYWAIT_PHYDOWN:
+			/* Has the device gone away? */
+			if (!attached_device_type)
+				phy_state = SMP_PHYWAIT_PHYUP;
+
+			break;
+
+		case SMP_PHYWAIT_PHYUP:
+			/* Has the device come back? */
+			if (attached_device_type)
+				phy_state = SMP_PHYWAIT_DONE;
+			break;
+
+		case SMP_PHYWAIT_DONE:
+			break;
+		}
+
+	}
+	dev_dbg(&ihost->pdev->dev, "%s: done\n",  __func__);
+}
+
 static int isci_reset_device(struct domain_device *dev, int hard_reset)
 {
 	struct isci_remote_device *idev = dev->lldd_dev;
 	struct sas_phy *phy = sas_find_local_phy(dev);
 	struct isci_host *ihost = dev_to_ihost(dev);
+	struct isci_port *iport = idev->isci_port;
 	enum sci_status status;
 	unsigned long flags;
 	int rc;
@@ -1432,6 +1672,10 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset)
 	/* Make sure all pending requests are able to be fully terminated. */
 	isci_device_clear_reset_pending(ihost, idev);
 
+	/* If this is a device on an expander, disable BCN processing. */
+	if (!scsi_is_sas_phy_local(phy))
+		set_bit(IPORT_BCN_BLOCKED, &iport->flags);
+
 	rc = sas_phy_reset(phy, hard_reset);
 
 	/* Terminate in-progress I/O now. */
@@ -1442,7 +1686,20 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset)
 	status = scic_remote_device_reset_complete(&idev->sci);
 	spin_unlock_irqrestore(&ihost->scic_lock, flags);
 
-	msleep(2000); /* just like mvsas */
+	/* If this is a device on an expander, bring the phy back up. */
+	if (!scsi_is_sas_phy_local(phy)) {
+		/* A phy reset will cause the device to go away then reappear.
+		 * Since libsas will take action on incoming BCNs (eg. remove
+		 * a device going through an SMP phy-control driven reset),
+		 * we need to wait until the phy comes back up before letting
+		 * discovery proceed in libsas.
+		 */
+		isci_wait_for_smp_phy_reset(idev, phy->number);
+
+		spin_lock_irqsave(&ihost->scic_lock, flags);
+		isci_port_bcn_enable(ihost, idev->isci_port);
+		spin_unlock_irqrestore(&ihost->scic_lock, flags);
+	}
 
 	if (status != SCI_SUCCESS) {
 		dev_warn(&ihost->pdev->dev,