Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/g…

…it/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Six minor fixes to device drivers and one to the multipath alua
  handler.

  The most extensive fix is the zfcp port remove prevention one, but
  it's impact is only s390"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: libsas: delete sas port if expander discover failed
  scsi: libsas: only clear phy->in_shutdown after shutdown event done
  scsi: scsi_dh_alua: Fix possible null-ptr-deref
  scsi: smartpqi: properly set both the DMA mask and the coherent DMA mask
  scsi: zfcp: fix to prevent port_remove with pure auto scan LUNs (only sdevs)
  scsi: zfcp: fix missing zfcp_port reference put on -EBUSY from port_remove
  scsi: libcxgbi: add a check for NULL pointer in cxgbi_check_route()

drivers/s390/scsi/zfcp_ext.h

@@ -167,6 +167,7 @@ extern const struct attribute_group *zfcp_port_attr_groups[];
 extern struct mutex zfcp_sysfs_port_units_mutex;
 extern struct device_attribute *zfcp_sysfs_sdev_attrs[];
 extern struct device_attribute *zfcp_sysfs_shost_attrs[];
+bool zfcp_sysfs_port_is_removing(const struct zfcp_port *const port);
 
 /* zfcp_unit.c */
 extern int zfcp_unit_add(struct zfcp_port *, u64);

drivers/s390/scsi/zfcp_scsi.c

@@ -129,6 +129,15 @@ static int zfcp_scsi_slave_alloc(struct scsi_device *sdev)
 
 	zfcp_sdev->erp_action.port = port;
 
+	mutex_lock(&zfcp_sysfs_port_units_mutex);
+	if (zfcp_sysfs_port_is_removing(port)) {
+		/* port is already gone */
+		mutex_unlock(&zfcp_sysfs_port_units_mutex);
+		put_device(&port->dev); /* undo zfcp_get_port_by_wwpn() */
+		return -ENXIO;
+	}
+	mutex_unlock(&zfcp_sysfs_port_units_mutex);
+
 	unit = zfcp_unit_find(port, zfcp_scsi_dev_lun(sdev));
 	if (unit)
 		put_device(&unit->dev);

drivers/s390/scsi/zfcp_sysfs.c

@@ -235,6 +235,53 @@ static ZFCP_DEV_ATTR(adapter, port_rescan, S_IWUSR, NULL,
 
 DEFINE_MUTEX(zfcp_sysfs_port_units_mutex);
 
+static void zfcp_sysfs_port_set_removing(struct zfcp_port *const port)
+{
+	lockdep_assert_held(&zfcp_sysfs_port_units_mutex);
+	atomic_set(&port->units, -1);
+}
+
+bool zfcp_sysfs_port_is_removing(const struct zfcp_port *const port)
+{
+	lockdep_assert_held(&zfcp_sysfs_port_units_mutex);
+	return atomic_read(&port->units) == -1;
+}
+
+static bool zfcp_sysfs_port_in_use(struct zfcp_port *const port)
+{
+	struct zfcp_adapter *const adapter = port->adapter;
+	unsigned long flags;
+	struct scsi_device *sdev;
+	bool in_use = true;
+
+	mutex_lock(&zfcp_sysfs_port_units_mutex);
+	if (atomic_read(&port->units) > 0)
+		goto unlock_port_units_mutex; /* zfcp_unit(s) under port */
+
+	spin_lock_irqsave(adapter->scsi_host->host_lock, flags);
+	__shost_for_each_device(sdev, adapter->scsi_host) {
+		const struct zfcp_scsi_dev *zsdev = sdev_to_zfcp(sdev);
+
+		if (sdev->sdev_state == SDEV_DEL ||
+		    sdev->sdev_state == SDEV_CANCEL)
+			continue;
+		if (zsdev->port != port)
+			continue;
+		/* alive scsi_device under port of interest */
+		goto unlock_host_lock;
+	}
+
+	/* port is about to be removed, so no more unit_add or slave_alloc */
+	zfcp_sysfs_port_set_removing(port);
+	in_use = false;
+
+unlock_host_lock:
+	spin_unlock_irqrestore(adapter->scsi_host->host_lock, flags);
+unlock_port_units_mutex:
+	mutex_unlock(&zfcp_sysfs_port_units_mutex);
+	return in_use;
+}
+
 static ssize_t zfcp_sysfs_port_remove_store(struct device *dev,
 					    struct device_attribute *attr,
 					    const char *buf, size_t count)
@@ -257,15 +304,11 @@ static ssize_t zfcp_sysfs_port_remove_store(struct device *dev,
 	else
 		retval = 0;
 
-	mutex_lock(&zfcp_sysfs_port_units_mutex);
-	if (atomic_read(&port->units) > 0) {
+	if (zfcp_sysfs_port_in_use(port)) {
 		retval = -EBUSY;
-		mutex_unlock(&zfcp_sysfs_port_units_mutex);
+		put_device(&port->dev); /* undo zfcp_get_port_by_wwpn() */
 		goto out;
 	}
-	/* port is about to be removed, so no more unit_add */
-	atomic_set(&port->units, -1);
-	mutex_unlock(&zfcp_sysfs_port_units_mutex);
 
 	write_lock_irq(&adapter->port_list_lock);
 	list_del(&port->list);

drivers/s390/scsi/zfcp_unit.c

@@ -124,7 +124,7 @@ int zfcp_unit_add(struct zfcp_port *port, u64 fcp_lun)
 	int retval = 0;
 
 	mutex_lock(&zfcp_sysfs_port_units_mutex);
-	if (atomic_read(&port->units) == -1) {
+	if (zfcp_sysfs_port_is_removing(port)) {
 		/* port is already gone */
 		retval = -ENODEV;
 		goto out;
@@ -168,8 +168,14 @@ int zfcp_unit_add(struct zfcp_port *port, u64 fcp_lun)
 	write_lock_irq(&port->unit_list_lock);
 	list_add_tail(&unit->list, &port->unit_list);
 	write_unlock_irq(&port->unit_list_lock);
+	/*
+	 * lock order: shost->scan_mutex before zfcp_sysfs_port_units_mutex
+	 * due to      zfcp_unit_scsi_scan() => zfcp_scsi_slave_alloc()
+	 */
+	mutex_unlock(&zfcp_sysfs_port_units_mutex);
 
 	zfcp_unit_scsi_scan(unit);
+	return retval;
 
 out:
 	mutex_unlock(&zfcp_sysfs_port_units_mutex);

drivers/scsi/cxgbi/libcxgbi.c

@@ -639,6 +639,10 @@ cxgbi_check_route(struct sockaddr *dst_addr, int ifindex)
 
 	if (ndev->flags & IFF_LOOPBACK) {
 		ndev = ip_dev_find(&init_net, daddr->sin_addr.s_addr);
+		if (!ndev) {
+			err = -ENETUNREACH;
+			goto rel_neigh;
+		}
 		mtu = ndev->mtu;
 		pr_info("rt dev %s, loopback -> %s, mtu %u.\n",
 			n->dev->name, ndev->name, mtu);

drivers/scsi/device_handler/scsi_dh_alua.c

@@ -1160,10 +1160,8 @@ static int __init alua_init(void)
 	int r;
 
 	kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0);
-	if (!kaluad_wq) {
-		/* Temporary failure, bypass */
-		return SCSI_DH_DEV_TEMP_BUSY;
-	}
+	if (!kaluad_wq)
+		return -ENOMEM;
 
 	r = scsi_register_device_handler(&alua_dh);
 	if (r != 0) {

drivers/scsi/libsas/sas_expander.c

@@ -1019,6 +1019,8 @@ static struct domain_device *sas_ex_discover_expander(
 		list_del(&child->dev_list_node);
 		spin_unlock_irq(&parent->port->dev_list_lock);
 		sas_put_device(child);
+		sas_port_delete(phy->port);
+		phy->port = NULL;
 		return NULL;
 	}
 	list_add_tail(&child->siblings, &parent->ex_dev.children);

drivers/scsi/libsas/sas_phy.c

@@ -35,7 +35,6 @@ static void sas_phye_loss_of_signal(struct work_struct *work)
 	struct asd_sas_event *ev = to_asd_sas_event(work);
 	struct asd_sas_phy *phy = ev->phy;
 
-	phy->in_shutdown = 0;
 	phy->error = 0;
 	sas_deform_port(phy, 1);
 }
@@ -45,7 +44,6 @@ static void sas_phye_oob_done(struct work_struct *work)
 	struct asd_sas_event *ev = to_asd_sas_event(work);
 	struct asd_sas_phy *phy = ev->phy;
 
-	phy->in_shutdown = 0;
 	phy->error = 0;
 }
 
@@ -126,6 +124,7 @@ static void sas_phye_shutdown(struct work_struct *work)
 				  ret);
 	} else
 		pr_notice("phy%d is not enabled, cannot shutdown\n", phy->id);
+	phy->in_shutdown = 0;
 }
 
 /* ---------- Phy class registration ---------- */

drivers/scsi/smartpqi/smartpqi_init.c

@@ -7291,7 +7291,7 @@ static int pqi_pci_init(struct pqi_ctrl_info *ctrl_info)
 	else
 		mask = DMA_BIT_MASK(32);
 
-	rc = dma_set_mask(&ctrl_info->pci_dev->dev, mask);
+	rc = dma_set_mask_and_coherent(&ctrl_info->pci_dev->dev, mask);
 	if (rc) {
 		dev_err(&ctrl_info->pci_dev->dev, "failed to set DMA mask\n");
 		goto disable_device;