s390/pci: unify de-/configure for slots and events

A zPCI event with PEC 0x0301 for an existing zPCI device goes through
the same actions as enable_slot(). Similarly a zPCI event with PEC
0x0303 does the same steps as disable_slot().
We can thus unify both actions as zpci_configure_device() respectively
zpci_deconfigure_device().

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

4 files changed, 100 insertions, 88 deletions

diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 5ed11936dc3b..c454dfb9fc4b 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -204,6 +204,9 @@ int zpci_create_device(u32 fid, u32 fh, enum zpci_state state);
 void zpci_remove_device(struct zpci_dev *zdev, bool set_error);
 int zpci_enable_device(struct zpci_dev *);
 int zpci_disable_device(struct zpci_dev *);
+int zpci_configure_device(struct zpci_dev *zdev, u32 fh);
+int zpci_deconfigure_device(struct zpci_dev *zdev);
+
 int zpci_register_ioat(struct zpci_dev *, u8, u64, u64, u64);
 int zpci_unregister_ioat(struct zpci_dev *, u8);
 void zpci_remove_reserved_devices(void);
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 5d6b838c0f22..6d84ec8f1dd6 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -668,7 +668,6 @@ out_dma:
 out:
 	return rc;
 }
-EXPORT_SYMBOL_GPL(zpci_enable_device);
 
 int zpci_disable_device(struct zpci_dev *zdev)
 {
@@ -679,7 +678,6 @@ int zpci_disable_device(struct zpci_dev *zdev)
 	 */
 	return clp_disable_fh(zdev);
 }
-EXPORT_SYMBOL_GPL(zpci_disable_device);
 
 /* zpci_remove_device - Removes the given zdev from the PCI core
  * @zdev: the zdev to be removed from the PCI core
@@ -779,6 +777,93 @@ error:
 	return rc;
 }
 
+/**
+ * zpci_configure_device() - Configure a zpci_dev
+ * @zdev: The zpci_dev to be configured
+ * @fh: The general function handle supplied by the platform
+ *
+ * Configuring a device includes the configuration itself, if not done by the
+ * platform, enabling, scanning and adding it to the common code PCI subsystem.
+ * If any failure occurs, the zpci_dev is left in Standby.
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+int zpci_configure_device(struct zpci_dev *zdev, u32 fh)
+{
+	struct pci_dev *pdev;
+	int rc;
+
+	zdev->fh = fh;
+	if (zdev->state != ZPCI_FN_STATE_CONFIGURED) {
+		rc = sclp_pci_configure(zdev->fid);
+		zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, rc);
+		if (rc)
+			return rc;
+		zdev->state = ZPCI_FN_STATE_CONFIGURED;
+	}
+
+	rc = zpci_enable_device(zdev);
+	if (rc)
+		goto error;
+
+	/* the PCI function will be scanned once function 0 appears */
+	if (!zdev->zbus->bus)
+		return 0;
+
+	pdev = pci_scan_single_device(zdev->zbus->bus, zdev->devfn);
+	if (!pdev)
+		goto error_disable;
+
+	pci_bus_add_device(pdev);
+	pci_lock_rescan_remove();
+	pci_bus_add_devices(zdev->zbus->bus);
+	pci_unlock_rescan_remove();
+	return 0;
+
+error_disable:
+	zpci_disable_device(zdev);
+error:
+	if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {
+		rc = sclp_pci_deconfigure(zdev->fid);
+		zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, rc);
+		if (!rc)
+			zdev->state = ZPCI_FN_STATE_STANDBY;
+	}
+	return rc;
+}
+
+/**
+ * zpci_deconfigure_device() - Deconfigure a zpci_dev
+ * @zdev: The zpci_dev to configure
+ *
+ * Deconfigure a zPCI function that is currently configured and possibly known
+ * to the common code PCI subsystem.
+ * If any failure occurs the device is left as is.
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+int zpci_deconfigure_device(struct zpci_dev *zdev)
+{
+	int rc;
+
+	if (zdev->zbus->bus)
+		zpci_remove_device(zdev, false);
+
+	if (zdev_enabled(zdev)) {
+		rc = zpci_disable_device(zdev);
+		if (rc)
+			return rc;
+	}
+
+	rc = sclp_pci_deconfigure(zdev->fid);
+	zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, rc);
+	if (rc)
+		return rc;
+	zdev->state = ZPCI_FN_STATE_STANDBY;
+
+	return 0;
+}
+
 void zpci_release_device(struct kref *kref)
 {
 	struct zpci_dev *zdev = container_of(kref, struct zpci_dev, kref);
diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c
index 0474ff8c6dbd..2676df9816f0 100644
--- a/arch/s390/pci/pci_event.c
+++ b/arch/s390/pci/pci_event.c
@@ -98,8 +98,6 @@ static void zpci_event_hard_deconfigured(struct zpci_dev *zdev, u32 fh)
 static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 {
 	struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
-	struct pci_dev *pdev;
-	int ret;
 
 	zpci_err("avail CCDF:\n");
 	zpci_err_hex(ccdf, sizeof(*ccdf));
@@ -113,46 +111,20 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 		/* the configuration request may be stale */
 		if (zdev->state != ZPCI_FN_STATE_STANDBY)
 			break;
-		zdev->fh = ccdf->fh;
 		zdev->state = ZPCI_FN_STATE_CONFIGURED;
-		ret = zpci_enable_device(zdev);
-		if (ret)
-			break;
-
-		/* the PCI function will be scanned once function 0 appears */
-		if (!zdev->zbus->bus)
-			break;
-
-		pdev = pci_scan_single_device(zdev->zbus->bus, zdev->devfn);
-		if (!pdev)
-			break;
-
-		pci_bus_add_device(pdev);
-		pci_lock_rescan_remove();
-		pci_bus_add_devices(zdev->zbus->bus);
-		pci_unlock_rescan_remove();
+		zpci_configure_device(zdev, ccdf->fh);
 		break;
 	case 0x0302: /* Reserved -> Standby */
-		if (!zdev) {
+		if (!zdev)
 			zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_STANDBY);
-			break;
-		}
-		zdev->fh = ccdf->fh;
+		else
+			zdev->fh = ccdf->fh;
 		break;
 	case 0x0303: /* Deconfiguration requested */
-		if (!zdev)
-			break;
-		zpci_remove_device(zdev, false);
-
-		ret = zpci_disable_device(zdev);
-		if (ret)
-			break;
-
-		ret = sclp_pci_deconfigure(zdev->fid);
-		zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
-		if (!ret)
-			zdev->state = ZPCI_FN_STATE_STANDBY;
-
+		if (zdev) {
+			zdev->fh = ccdf->fh;
+			zpci_deconfigure_device(zdev);
+		}
 		break;
 	case 0x0304: /* Configured -> Standby|Reserved */
 		if (zdev)
diff --git a/drivers/pci/hotplug/s390_pci_hpc.c b/drivers/pci/hotplug/s390_pci_hpc.c
index c93c09ae4b04..154532663a70 100644
--- a/drivers/pci/hotplug/s390_pci_hpc.c
+++ b/drivers/pci/hotplug/s390_pci_hpc.c
@@ -20,56 +20,15 @@
 
 #define SLOT_NAME_SIZE	10
 
-static inline int zdev_configure(struct zpci_dev *zdev)
-{
-	int ret = sclp_pci_configure(zdev->fid);
-
-	zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, ret);
-	if (!ret)
-		zdev->state = ZPCI_FN_STATE_CONFIGURED;
-
-	return ret;
-}
-
-static inline int zdev_deconfigure(struct zpci_dev *zdev)
-{
-	int ret = sclp_pci_deconfigure(zdev->fid);
-
-	zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
-	if (!ret)
-		zdev->state = ZPCI_FN_STATE_STANDBY;
-
-	return ret;
-}
-
 static int enable_slot(struct hotplug_slot *hotplug_slot)
 {
 	struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
 					     hotplug_slot);
-	struct zpci_bus *zbus = zdev->zbus;
-	int rc;
 
 	if (zdev->state != ZPCI_FN_STATE_STANDBY)
 		return -EIO;
 
-	rc = zdev_configure(zdev);
-	if (rc)
-		return rc;
-
-	rc = zpci_enable_device(zdev);
-	if (rc)
-		goto out_deconfigure;
-
-	pci_scan_slot(zbus->bus, zdev->devfn);
-	pci_lock_rescan_remove();
-	pci_bus_add_devices(zbus->bus);
-	pci_unlock_rescan_remove();
-
-	return rc;
-
-out_deconfigure:
-	zdev_deconfigure(zdev);
-	return rc;
+	return zpci_configure_device(zdev, zdev->fh);
 }
 
 static int disable_slot(struct hotplug_slot *hotplug_slot)
@@ -77,7 +36,6 @@ static int disable_slot(struct hotplug_slot *hotplug_slot)
 	struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
 					     hotplug_slot);
 	struct pci_dev *pdev;
-	int rc;
 
 	if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
 		return -EIO;
@@ -89,13 +47,7 @@ static int disable_slot(struct hotplug_slot *hotplug_slot)
 	}
 	pci_dev_put(pdev);
 
-	zpci_remove_device(zdev, false);
-
-	rc = zpci_disable_device(zdev);
-	if (rc)
-		return rc;
-
-	return zdev_deconfigure(zdev);
+	return zpci_deconfigure_device(zdev);
 }
 
 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)