[PATCH net-next 4/4] net: mana: Support hibernation and kexec

[Dexuan Cui <decui@microsoft.com>]

Implement the suspend/resume/shutdown callbacks for hibernation/kexec.

Add mana_gd_setup() and mana_gd_cleanup() for some common code, and
use them in the mand_gd_* callbacks.

Reuse mana_probe/remove() for the hibernation path.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
---
 .../net/ethernet/microsoft/mana/gdma_main.c   | 140 +++++++++++++-----
 drivers/net/ethernet/microsoft/mana/mana.h    |   4 +-
 drivers/net/ethernet/microsoft/mana/mana_en.c |  72 +++++++--
 3 files changed, 164 insertions(+), 52 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c
index 599dfd5e6090..c96ac81212f7 100644
--- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
+++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
@@ -1258,6 +1258,52 @@ static void mana_gd_remove_irqs(struct pci_dev *pdev)
 	gc->irq_contexts = NULL;
 }
 
+static int mana_gd_setup(struct pci_dev *pdev)
+{
+	struct gdma_context *gc = pci_get_drvdata(pdev);
+	int err;
+
+	mana_gd_init_registers(pdev);
+	mana_smc_init(&gc->shm_channel, gc->dev, gc->shm_base);
+
+	err = mana_gd_setup_irqs(pdev);
+	if (err)
+		return err;
+
+	err = mana_hwc_create_channel(gc);
+	if (err)
+		goto remove_irq;
+
+	err = mana_gd_verify_vf_version(pdev);
+	if (err)
+		goto destroy_hwc;
+
+	err = mana_gd_query_max_resources(pdev);
+	if (err)
+		goto destroy_hwc;
+
+	err = mana_gd_detect_devices(pdev);
+	if (err)
+		goto destroy_hwc;
+
+	return 0;
+
+destroy_hwc:
+	mana_hwc_destroy_channel(gc);
+remove_irq:
+	mana_gd_remove_irqs(pdev);
+	return err;
+}
+
+static void mana_gd_cleanup(struct pci_dev *pdev)
+{
+	struct gdma_context *gc = pci_get_drvdata(pdev);
+
+	mana_hwc_destroy_channel(gc);
+
+	mana_gd_remove_irqs(pdev);
+}
+
 static int mana_gd_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	struct gdma_context *gc;
@@ -1287,6 +1333,9 @@ static int mana_gd_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (!gc)
 		goto release_region;
 
+	mutex_init(&gc->eq_test_event_mutex);
+	pci_set_drvdata(pdev, gc);
+
 	bar0_va = pci_iomap(pdev, bar, 0);
 	if (!bar0_va)
 		goto free_gc;
@@ -1294,47 +1343,23 @@ static int mana_gd_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	gc->bar0_va = bar0_va;
 	gc->dev = &pdev->dev;
 
-	pci_set_drvdata(pdev, gc);
-
-	mana_gd_init_registers(pdev);
 
-	mana_smc_init(&gc->shm_channel, gc->dev, gc->shm_base);
-
-	err = mana_gd_setup_irqs(pdev);
+	err = mana_gd_setup(pdev);
 	if (err)
 		goto unmap_bar;
 
-	mutex_init(&gc->eq_test_event_mutex);
-
-	err = mana_hwc_create_channel(gc);
+	err = mana_probe(&gc->mana, false);
 	if (err)
-		goto remove_irq;
-
-	err = mana_gd_verify_vf_version(pdev);
-	if (err)
-		goto remove_irq;
-
-	err = mana_gd_query_max_resources(pdev);
-	if (err)
-		goto remove_irq;
-
-	err = mana_gd_detect_devices(pdev);
-	if (err)
-		goto remove_irq;
-
-	err = mana_probe(&gc->mana);
-	if (err)
-		goto clean_up_gdma;
+		goto cleanup_gd;
 
 	return 0;
 
-clean_up_gdma:
-	mana_hwc_destroy_channel(gc);
-remove_irq:
-	mana_gd_remove_irqs(pdev);
+cleanup_gd:
+	mana_gd_cleanup(pdev);
 unmap_bar:
 	pci_iounmap(pdev, bar0_va);
 free_gc:
+	pci_set_drvdata(pdev, NULL);
 	vfree(gc);
 release_region:
 	pci_release_regions(pdev);
@@ -1349,11 +1374,9 @@ static void mana_gd_remove(struct pci_dev *pdev)
 {
 	struct gdma_context *gc = pci_get_drvdata(pdev);
 
-	mana_remove(&gc->mana);
+	mana_remove(&gc->mana, false);
 
-	mana_hwc_destroy_channel(gc);
-
-	mana_gd_remove_irqs(pdev);
+	mana_gd_cleanup(pdev);
 
 	pci_iounmap(pdev, gc->bar0_va);
 
@@ -1364,6 +1387,52 @@ static void mana_gd_remove(struct pci_dev *pdev)
 	pci_disable_device(pdev);
 }
 
+/* The 'state' parameter is not used. */
+static int mana_gd_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	struct gdma_context *gc = pci_get_drvdata(pdev);
+
+	mana_remove(&gc->mana, true);
+
+	mana_gd_cleanup(pdev);
+
+	return 0;
+}
+
+/* In case the NIC hardware stops working, the suspend and resume callbacks will
+ * fail -- if this happens, it's safer to just report an error than try to undo
+ * what has been done.
+ */
+static int mana_gd_resume(struct pci_dev *pdev)
+{
+	struct gdma_context *gc = pci_get_drvdata(pdev);
+	int err;
+
+	err = mana_gd_setup(pdev);
+	if (err)
+		return err;
+
+	err = mana_probe(&gc->mana, true);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/* Quiesce the device for kexec. This is also called upon reboot/shutdown. */
+static void mana_gd_shutdown(struct pci_dev *pdev)
+{
+	struct gdma_context *gc = pci_get_drvdata(pdev);
+
+	dev_info(&pdev->dev, "Shutdown was calledd\n");
+
+	mana_remove(&gc->mana, true);
+
+	mana_gd_cleanup(pdev);
+
+	pci_disable_device(pdev);
+}
+
 #ifndef PCI_VENDOR_ID_MICROSOFT
 #define PCI_VENDOR_ID_MICROSOFT 0x1414
 #endif
@@ -1378,6 +1447,9 @@ static struct pci_driver mana_driver = {
 	.id_table	= mana_id_table,
 	.probe		= mana_gd_probe,
 	.remove		= mana_gd_remove,
+	.suspend	= mana_gd_suspend,
+	.resume		= mana_gd_resume,
+	.shutdown	= mana_gd_shutdown,
 };
 
 module_pci_driver(mana_driver);
diff --git a/drivers/net/ethernet/microsoft/mana/mana.h b/drivers/net/ethernet/microsoft/mana/mana.h
index fc98a5ba5ed0..d047ee876f12 100644
--- a/drivers/net/ethernet/microsoft/mana/mana.h
+++ b/drivers/net/ethernet/microsoft/mana/mana.h
@@ -374,8 +374,8 @@ int mana_alloc_queues(struct net_device *ndev);
 int mana_attach(struct net_device *ndev);
 int mana_detach(struct net_device *ndev, bool from_close);
 
-int mana_probe(struct gdma_dev *gd);
-void mana_remove(struct gdma_dev *gd);
+int mana_probe(struct gdma_dev *gd, bool resuming);
+void mana_remove(struct gdma_dev *gd, bool suspending);
 
 extern const struct ethtool_ops mana_ethtool_ops;
 
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 4ff5a1fc506f..820585d45a61 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -1828,11 +1828,12 @@ static int mana_probe_port(struct mana_context *ac, int port_idx,
 	return err;
 }
 
-int mana_probe(struct gdma_dev *gd)
+int mana_probe(struct gdma_dev *gd, bool resuming)
 {
 	struct gdma_context *gc = gd->gdma_context;
+	struct mana_context *ac = gd->driver_data;
 	struct device *dev = gc->dev;
-	struct mana_context *ac;
+	u16 num_ports = 0;
 	int err;
 	int i;
 
@@ -1844,44 +1845,70 @@ int mana_probe(struct gdma_dev *gd)
 	if (err)
 		return err;
 
-	ac = kzalloc(sizeof(*ac), GFP_KERNEL);
-	if (!ac)
-		return -ENOMEM;
+	if (!resuming) {
+		ac = kzalloc(sizeof(*ac), GFP_KERNEL);
+		if (!ac)
+			return -ENOMEM;
 
-	ac->gdma_dev = gd;
-	ac->num_ports = 1;
-	gd->driver_data = ac;
+		ac->gdma_dev = gd;
+		gd->driver_data = ac;
+	}
 
 	err = mana_create_eq(ac);
 	if (err)
 		goto out;
 
 	err = mana_query_device_cfg(ac, MANA_MAJOR_VERSION, MANA_MINOR_VERSION,
-				    MANA_MICRO_VERSION, &ac->num_ports);
+				    MANA_MICRO_VERSION, &num_ports);
 	if (err)
 		goto out;
 
+	if (!resuming) {
+		ac->num_ports = num_ports;
+	} else {
+		if (ac->num_ports != num_ports) {
+			dev_err(dev, "The number of vPorts changed: %d->%d\n",
+				ac->num_ports, num_ports);
+			err = -EPROTO;
+			goto out;
+		}
+	}
+
+	if (ac->num_ports == 0)
+		dev_err(dev, "Failed to detect any vPort\n");
+
 	if (ac->num_ports > MAX_PORTS_IN_MANA_DEV)
 		ac->num_ports = MAX_PORTS_IN_MANA_DEV;
 
-	for (i = 0; i < ac->num_ports; i++) {
-		err = mana_probe_port(ac, i, &ac->ports[i]);
-		if (err)
-			break;
+	if (!resuming) {
+		for (i = 0; i < ac->num_ports; i++) {
+			err = mana_probe_port(ac, i, &ac->ports[i]);
+			if (err)
+				break;
+		}
+	} else {
+		for (i = 0; i < ac->num_ports; i++) {
+			rtnl_lock();
+			err = mana_attach(ac->ports[i]);
+			rtnl_unlock();
+			if (err)
+				break;
+		}
 	}
 out:
 	if (err)
-		mana_remove(gd);
+		mana_remove(gd, false);
 
 	return err;
 }
 
-void mana_remove(struct gdma_dev *gd)
+void mana_remove(struct gdma_dev *gd, bool suspending)
 {
 	struct gdma_context *gc = gd->gdma_context;
 	struct mana_context *ac = gd->driver_data;
 	struct device *dev = gc->dev;
 	struct net_device *ndev;
+	int err;
 	int i;
 
 	for (i = 0; i < ac->num_ports; i++) {
@@ -1897,7 +1924,16 @@ void mana_remove(struct gdma_dev *gd)
 		 */
 		rtnl_lock();
 
-		mana_detach(ndev, false);
+		err = mana_detach(ndev, false);
+		if (err)
+			netdev_err(ndev, "Failed to detach vPort %d: %d\n",
+				   i, err);
+
+		if (suspending) {
+			/* No need to unregister the ndev. */
+			rtnl_unlock();
+			continue;
+		}
 
 		unregister_netdevice(ndev);
 
@@ -1910,6 +1946,10 @@ void mana_remove(struct gdma_dev *gd)
 
 out:
 	mana_gd_deregister_device(gd);
+
+	if (suspending)
+		return;
+
 	gd->driver_data = NULL;
 	gd->gdma_context = NULL;
 	kfree(ac);
-- 
2.17.1