[PATCH v7 1/6] isci: kill iphy->isci_port lookups

[Dan Williams <dan.j.williams@intel.com>]

This field is a holdover from the OS abstraction conversion.  The stable
phy to port lookups are done via iphy->ownining_port under scic_lock.
After this conversion to use port->lldd_port the only volatile lookup is
the initial lookup in isci_port_formed().  After that point any lookup
via a successfully notified domain_device is guaranteed to be valid
until the domain_device is destroyed.

Delete ->start_complete as it is only set once and is set as a
consequence of the port going link up, by definition of getting a port
formed event the port is "ready".

While we are correcting port lookups also move the asd_sas_port table
out from under the isci_port.  This is to preclude any temptation to use
container_of() to convert an asd_sas_port to an isci_port, the
association is dynamic and under libsas control.

Tested-by: Maciej Trela <maciej.trela@intel.com>
Cc: David Milburn <dmilburn@redhat.com>
[dmilburn@redhat.com: fix i686 compile error]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/scsi/isci/host.h          |   19 --------
 drivers/scsi/isci/init.c          |    7 ---
 drivers/scsi/isci/phy.c           |   18 +++++---
 drivers/scsi/isci/phy.h           |    1 
 drivers/scsi/isci/port.c          |   84 +++++++++++++++++++++++++++----------
 drivers/scsi/isci/port.h          |    2 -
 drivers/scsi/isci/remote_device.c |   29 ++++---------
 7 files changed, 83 insertions(+), 77 deletions(-)

diff --git a/drivers/scsi/isci/host.h b/drivers/scsi/isci/host.h
index 646051a..26d4cba 100644
--- a/drivers/scsi/isci/host.h
+++ b/drivers/scsi/isci/host.h
@@ -187,6 +187,7 @@ struct isci_host {
 	int id; /* unique within a given pci device */
 	struct isci_phy phys[SCI_MAX_PHYS];
 	struct isci_port ports[SCI_MAX_PORTS + 1]; /* includes dummy port */
+	struct asd_sas_port sas_ports[SCI_MAX_PORTS];
 	struct sas_ha_struct sas_ha;
 
 	spinlock_t state_lock;
@@ -393,24 +394,6 @@ static inline int sci_remote_device_node_count(struct isci_remote_device *idev)
 #define sci_controller_clear_invalid_phy(controller, phy) \
 	((controller)->invalid_phy_mask &= ~(1 << (phy)->phy_index))
 
-static inline struct device *sciphy_to_dev(struct isci_phy *iphy)
-{
-
-	if (!iphy || !iphy->isci_port || !iphy->isci_port->isci_host)
-		return NULL;
-
-	return &iphy->isci_port->isci_host->pdev->dev;
-}
-
-static inline struct device *sciport_to_dev(struct isci_port *iport)
-{
-
-	if (!iport || !iport->isci_host)
-		return NULL;
-
-	return &iport->isci_host->pdev->dev;
-}
-
 static inline struct device *scirdev_to_dev(struct isci_remote_device *idev)
 {
 	if (!idev || !idev->isci_port || !idev->isci_port->isci_host)
diff --git a/drivers/scsi/isci/init.c b/drivers/scsi/isci/init.c
index f988c16..59f2ae7 100644
--- a/drivers/scsi/isci/init.c
+++ b/drivers/scsi/isci/init.c
@@ -233,18 +233,13 @@ static int isci_register_sas_ha(struct isci_host *isci_host)
 	if (!sas_ports)
 		return -ENOMEM;
 
-	/*----------------- Libsas Initialization Stuff----------------------
-	 * Set various fields in the sas_ha struct:
-	 */
-
 	sas_ha->sas_ha_name = DRV_NAME;
 	sas_ha->lldd_module = THIS_MODULE;
 	sas_ha->sas_addr    = &isci_host->phys[0].sas_addr[0];
 
-	/* set the array of phy and port structs.  */
 	for (i = 0; i < SCI_MAX_PHYS; i++) {
 		sas_phys[i] = &isci_host->phys[i].sas_phy;
-		sas_ports[i] = &isci_host->ports[i].sas_port;
+		sas_ports[i] = &isci_host->sas_ports[i];
 	}
 
 	sas_ha->sas_phy  = sas_phys;
diff --git a/drivers/scsi/isci/phy.c b/drivers/scsi/isci/phy.c
index 35f50c2..59f3d2e 100644
--- a/drivers/scsi/isci/phy.c
+++ b/drivers/scsi/isci/phy.c
@@ -67,6 +67,14 @@ enum sas_linkrate sci_phy_linkrate(struct isci_phy *iphy)
 	return iphy->max_negotiated_speed;
 }
 
+static struct device *sciphy_to_dev(struct isci_phy *iphy)
+{
+	struct isci_phy *table = iphy - iphy->phy_index;
+	struct isci_host *ihost = container_of(table, typeof(*ihost), phys[0]);
+
+	return &ihost->pdev->dev;
+}
+
 static enum sci_status
 sci_phy_transport_layer_initialization(struct isci_phy *iphy,
 				       struct scu_transport_layer_registers __iomem *reg)
@@ -1249,7 +1257,6 @@ void isci_phy_init(struct isci_phy *iphy, struct isci_host *ihost, int index)
 	sas_addr = cpu_to_be64(sci_sas_addr);
 	memcpy(iphy->sas_addr, &sas_addr, sizeof(sas_addr));
 
-	iphy->isci_port = NULL;
 	iphy->sas_phy.enabled = 0;
 	iphy->sas_phy.id = index;
 	iphy->sas_phy.sas_addr = &iphy->sas_addr[0];
@@ -1283,13 +1290,13 @@ int isci_phy_control(struct asd_sas_phy *sas_phy,
 {
 	int ret = 0;
 	struct isci_phy *iphy = sas_phy->lldd_phy;
-	struct isci_port *iport = iphy->isci_port;
+	struct asd_sas_port *port = sas_phy->port;
 	struct isci_host *ihost = sas_phy->ha->lldd_ha;
 	unsigned long flags;
 
 	dev_dbg(&ihost->pdev->dev,
 		"%s: phy %p; func %d; buf %p; isci phy %p, port %p\n",
-		__func__, sas_phy, func, buf, iphy, iport);
+		__func__, sas_phy, func, buf, iphy, port);
 
 	switch (func) {
 	case PHY_FUNC_DISABLE:
@@ -1306,11 +1313,10 @@ int isci_phy_control(struct asd_sas_phy *sas_phy,
 		break;
 
 	case PHY_FUNC_HARD_RESET:
-		if (!iport)
+		if (!port)
 			return -ENODEV;
 
-		/* Perform the port reset. */
-		ret = isci_port_perform_hard_reset(ihost, iport, iphy);
+		ret = isci_port_perform_hard_reset(ihost, port->lldd_port, iphy);
 
 		break;
 	case PHY_FUNC_GET_EVENTS: {
diff --git a/drivers/scsi/isci/phy.h b/drivers/scsi/isci/phy.h
index 67699c8..a5e1a9e 100644
--- a/drivers/scsi/isci/phy.h
+++ b/drivers/scsi/isci/phy.h
@@ -103,7 +103,6 @@ struct isci_phy {
 	struct scu_transport_layer_registers __iomem *transport_layer_registers;
 	struct scu_link_layer_registers __iomem *link_layer_registers;
 	struct asd_sas_phy sas_phy;
-	struct isci_port *isci_port;
 	u8 sas_addr[SAS_ADDR_SIZE];
 	union {
 		struct sas_identify_frame iaf;
diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c
index ac7f277..841bd48 100644
--- a/drivers/scsi/isci/port.c
+++ b/drivers/scsi/isci/port.c
@@ -60,6 +60,21 @@
 #define SCIC_SDS_PORT_HARD_RESET_TIMEOUT  (1000)
 #define SCU_DUMMY_INDEX    (0xFFFF)
 
+static struct device *sciport_to_dev(struct isci_port *iport)
+{
+	int i = iport->physical_port_index;
+	struct isci_port *table;
+	struct isci_host *ihost;
+
+	if (i == SCIC_SDS_DUMMY_PORT)
+		i = SCI_MAX_PORTS+1;
+
+	table = iport - i;
+	ihost = container_of(table, typeof(*ihost), ports[0]);
+
+	return &ihost->pdev->dev;
+}
+
 static void isci_port_change_state(struct isci_port *iport, enum isci_status status)
 {
 	unsigned long flags;
@@ -165,17 +180,13 @@ static void isci_port_link_up(struct isci_host *isci_host,
 	struct sci_port_properties properties;
 	unsigned long success = true;
 
-	BUG_ON(iphy->isci_port != NULL);
-
-	iphy->isci_port = iport;
-
 	dev_dbg(&isci_host->pdev->dev,
 		"%s: isci_port = %p\n",
 		__func__, iport);
 
 	spin_lock_irqsave(&iphy->sas_phy.frame_rcvd_lock, flags);
 
-	isci_port_change_state(iphy->isci_port, isci_starting);
+	isci_port_change_state(iport, isci_starting);
 
 	sci_port_get_properties(iport, &properties);
 
@@ -269,8 +280,6 @@ static void isci_port_link_down(struct isci_host *isci_host,
 	isci_host->sas_ha.notify_phy_event(&isci_phy->sas_phy,
 					   PHYE_LOSS_OF_SIGNAL);
 
-	isci_phy->isci_port = NULL;
-
 	dev_dbg(&isci_host->pdev->dev,
 		"%s: isci_port = %p - Done\n", __func__, isci_port);
 }
@@ -288,7 +297,6 @@ static void isci_port_ready(struct isci_host *isci_host, struct isci_port *isci_
 	dev_dbg(&isci_host->pdev->dev,
 		"%s: isci_port = %p\n", __func__, isci_port);
 
-	complete_all(&isci_port->start_complete);
 	isci_port_change_state(isci_port, isci_ready);
 	return;
 }
@@ -1633,7 +1641,6 @@ void isci_port_init(struct isci_port *iport, struct isci_host *ihost, int index)
 	INIT_LIST_HEAD(&iport->remote_dev_list);
 	INIT_LIST_HEAD(&iport->domain_dev_list);
 	spin_lock_init(&iport->state_lock);
-	init_completion(&iport->start_complete);
 	iport->isci_host = ihost;
 	isci_port_change_state(iport, isci_freed);
 }
@@ -1714,24 +1721,55 @@ int isci_port_perform_hard_reset(struct isci_host *ihost, struct isci_port *ipor
 	return ret;
 }
 
-/**
- * isci_port_deformed() - This function is called by libsas when a port becomes
- *    inactive.
- * @phy: This parameter specifies the libsas phy with the inactive port.
- *
- */
 void isci_port_deformed(struct asd_sas_phy *phy)
 {
-	pr_debug("%s: sas_phy = %p\n", __func__, phy);
+	struct isci_host *ihost = phy->ha->lldd_ha;
+	struct isci_port *iport = phy->port->lldd_port;
+	unsigned long flags;
+	int i;
+
+	/* we got a port notification on a port that was subsequently
+	 * torn down and libsas is just now catching up
+	 */
+	if (!iport)
+		return;
+
+	spin_lock_irqsave(&ihost->scic_lock, flags);
+	for (i = 0; i < SCI_MAX_PHYS; i++) {
+		if (iport->active_phy_mask & 1 << i)
+			break;
+	}
+	spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+	if (i >= SCI_MAX_PHYS)
+		dev_dbg(&ihost->pdev->dev, "%s: port: %ld\n",
+			__func__, (long) (iport - &ihost->ports[0]));
 }
 
-/**
- * isci_port_formed() - This function is called by libsas when a port becomes
- *    active.
- * @phy: This parameter specifies the libsas phy with the active port.
- *
- */
 void isci_port_formed(struct asd_sas_phy *phy)
 {
-	pr_debug("%s: sas_phy = %p, sas_port = %p\n", __func__, phy, phy->port);
+	struct isci_host *ihost = phy->ha->lldd_ha;
+	struct isci_phy *iphy = to_iphy(phy);
+	struct asd_sas_port *port = phy->port;
+	struct isci_port *iport;
+	unsigned long flags;
+	int i;
+
+	/* initial ports are formed as the driver is still initializing,
+	 * wait for that process to complete
+	 */
+	wait_for_start(ihost);
+
+	spin_lock_irqsave(&ihost->scic_lock, flags);
+	for (i = 0; i < SCI_MAX_PORTS; i++) {
+		iport = &ihost->ports[i];
+		if (iport->active_phy_mask & 1 << iphy->phy_index)
+			break;
+	}
+	spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+	if (i >= SCI_MAX_PORTS)
+		iport = NULL;
+
+	port->lldd_port = iport;
 }
diff --git a/drivers/scsi/isci/port.h b/drivers/scsi/isci/port.h
index cb5ffbc..83de4b4 100644
--- a/drivers/scsi/isci/port.h
+++ b/drivers/scsi/isci/port.h
@@ -92,11 +92,9 @@ enum isci_status {
 struct isci_port {
 	enum isci_status status;
 	struct isci_host *isci_host;
-	struct asd_sas_port sas_port;
 	struct list_head remote_dev_list;
 	spinlock_t state_lock;
 	struct list_head domain_dev_list;
-	struct completion start_complete;
 	struct completion hard_reset_complete;
 	enum sci_status hard_reset_status;
 	struct sci_base_state_machine sm;
diff --git a/drivers/scsi/isci/remote_device.c b/drivers/scsi/isci/remote_device.c
index b207cd3..49259e0 100644
--- a/drivers/scsi/isci/remote_device.c
+++ b/drivers/scsi/isci/remote_device.c
@@ -1377,31 +1377,18 @@ void isci_remote_device_gone(struct domain_device *dev)
  *
  * status, zero indicates success.
  */
-int isci_remote_device_found(struct domain_device *domain_dev)
+int isci_remote_device_found(struct domain_device *dev)
 {
-	struct isci_host *isci_host = dev_to_ihost(domain_dev);
-	struct isci_port *isci_port;
-	struct isci_phy *isci_phy;
-	struct asd_sas_port *sas_port;
-	struct asd_sas_phy *sas_phy;
+	struct isci_host *isci_host = dev_to_ihost(dev);
+	struct isci_port *isci_port = dev->port->lldd_port;
 	struct isci_remote_device *isci_device;
 	enum sci_status status;
 
 	dev_dbg(&isci_host->pdev->dev,
-		"%s: domain_device = %p\n", __func__, domain_dev);
+		"%s: domain_device = %p\n", __func__, dev);
 
-	wait_for_start(isci_host);
-
-	sas_port = domain_dev->port;
-	sas_phy = list_first_entry(&sas_port->phy_list, struct asd_sas_phy,
-				   port_phy_el);
-	isci_phy = to_iphy(sas_phy);
-	isci_port = isci_phy->isci_port;
-
-	/* we are being called for a device on this port,
-	 * so it has to come up eventually
-	 */
-	wait_for_completion(&isci_port->start_complete);
+	if (!isci_port)
+		return -ENODEV;
 
 	if ((isci_stopping == isci_port_get_state(isci_port)) ||
 	    (isci_stopped == isci_port_get_state(isci_port)))
@@ -1415,7 +1402,7 @@ int isci_remote_device_found(struct domain_device *domain_dev)
 	INIT_LIST_HEAD(&isci_device->node);
 
 	spin_lock_irq(&isci_host->scic_lock);
-	isci_device->domain_dev = domain_dev;
+	isci_device->domain_dev = dev;
 	isci_device->isci_port = isci_port;
 	list_add_tail(&isci_device->node, &isci_port->remote_dev_list);
 
@@ -1428,7 +1415,7 @@ int isci_remote_device_found(struct domain_device *domain_dev)
 
 	if (status == SCI_SUCCESS) {
 		/* device came up, advertise it to the world */
-		domain_dev->lldd_dev = isci_device;
+		dev->lldd_dev = isci_device;
 	} else
 		isci_put_device(isci_device);
 	spin_unlock_irq(&isci_host->scic_lock);