Merge branch 'ionic-FLR-support'

Shannon Nelson says:

====================
ionic: add FLR support

Add support for handing and recovering from a PCI FLR event.
This patchset first moves some code around to make it usable
from multiple paths, then adds the PCI error handler callbacks
for reset_prepare and reset_done.

Example test:
    echo 1 > /sys/bus/pci/devices/0000:2a:00.0/reset

v4:
 - don't remove ionic_dev_teardown() in ionic_probe() in patch 2/4
 - remove clear_bit() change from patch 3/4

v3:
Link: https://lore.kernel.org/netdev/20230717170001.30539-1-shannon.nelson@amd.com/
 - removed first patch, it is already merged into net

v2:
Link: https://lore.kernel.org/netdev/20230713192936.45152-1-shannon.nelson@amd.com/
 - removed redundant pci_save/restore_state() calls
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c

@@ -213,29 +213,18 @@ static int ionic_sriov_configure(struct pci_dev *pdev, int num_vfs)
 	return ret;
 }
 
-static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+static void ionic_clear_pci(struct ionic *ionic)
 {
-	struct device *dev = &pdev->dev;
-	struct ionic *ionic;
-	int num_vfs;
-	int err;
-
-	ionic = ionic_devlink_alloc(dev);
-	if (!ionic)
-		return -ENOMEM;
-
-	ionic->pdev = pdev;
-	ionic->dev = dev;
-	pci_set_drvdata(pdev, ionic);
-	mutex_init(&ionic->dev_cmd_lock);
+	ionic_unmap_bars(ionic);
+	pci_release_regions(ionic->pdev);
+	pci_disable_device(ionic->pdev);
+}
 
-	/* Query system for DMA addressing limitation for the device. */
-	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(IONIC_ADDR_LEN));
-	if (err) {
-		dev_err(dev, "Unable to obtain 64-bit DMA for consistent allocations, aborting.  err=%d\n",
-			err);
-		goto err_out_clear_drvdata;
-	}
+static int ionic_setup_one(struct ionic *ionic)
+{
+	struct pci_dev *pdev = ionic->pdev;
+	struct device *dev = ionic->dev;
+	int err;
 
 	ionic_debugfs_add_dev(ionic);
 
@@ -249,20 +238,19 @@ static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	err = pci_request_regions(pdev, IONIC_DRV_NAME);
 	if (err) {
 		dev_err(dev, "Cannot request PCI regions: %d, aborting\n", err);
-		goto err_out_pci_disable_device;
+		goto err_out_clear_pci;
 	}
-
 	pcie_print_link_status(pdev);
 
 	err = ionic_map_bars(ionic);
 	if (err)
-		goto err_out_pci_release_regions;
+		goto err_out_clear_pci;
 
 	/* Configure the device */
 	err = ionic_setup(ionic);
 	if (err) {
 		dev_err(dev, "Cannot setup device: %d, aborting\n", err);
-		goto err_out_unmap_bars;
+		goto err_out_clear_pci;
 	}
 	pci_set_master(pdev);
 
@@ -279,24 +267,64 @@ static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto err_out_teardown;
 	}
 
-	/* Configure the ports */
+	/* Configure the port */
 	err = ionic_port_identify(ionic);
 	if (err) {
 		dev_err(dev, "Cannot identify port: %d, aborting\n", err);
-		goto err_out_reset;
+		goto err_out_teardown;
 	}
 
 	err = ionic_port_init(ionic);
 	if (err) {
 		dev_err(dev, "Cannot init port: %d, aborting\n", err);
-		goto err_out_reset;
+		goto err_out_teardown;
+	}
+
+	return 0;
+
+err_out_teardown:
+	ionic_dev_teardown(ionic);
+err_out_clear_pci:
+	ionic_clear_pci(ionic);
+err_out_debugfs_del_dev:
+	ionic_debugfs_del_dev(ionic);
+
+	return err;
+}
+
+static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	struct device *dev = &pdev->dev;
+	struct ionic *ionic;
+	int num_vfs;
+	int err;
+
+	ionic = ionic_devlink_alloc(dev);
+	if (!ionic)
+		return -ENOMEM;
+
+	ionic->pdev = pdev;
+	ionic->dev = dev;
+	pci_set_drvdata(pdev, ionic);
+	mutex_init(&ionic->dev_cmd_lock);
+
+	/* Query system for DMA addressing limitation for the device. */
+	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(IONIC_ADDR_LEN));
+	if (err) {
+		dev_err(dev, "Unable to obtain 64-bit DMA for consistent allocations, aborting.  err=%d\n",
+			err);
+		goto err_out;
 	}
 
+	err = ionic_setup_one(ionic);
+	if (err)
+		goto err_out;
+
 	/* Allocate and init the LIF */
 	err = ionic_lif_size(ionic);
 	if (err) {
 		dev_err(dev, "Cannot size LIF: %d, aborting\n", err);
-		goto err_out_port_reset;
+		goto err_out_pci;
 	}
 
 	err = ionic_lif_alloc(ionic);
@@ -347,21 +375,10 @@ static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	ionic->lif = NULL;
 err_out_free_irqs:
 	ionic_bus_free_irq_vectors(ionic);
-err_out_port_reset:
-	ionic_port_reset(ionic);
-err_out_reset:
-	ionic_reset(ionic);
-err_out_teardown:
+err_out_pci:
 	ionic_dev_teardown(ionic);
-err_out_unmap_bars:
-	ionic_unmap_bars(ionic);
-err_out_pci_release_regions:
-	pci_release_regions(pdev);
-err_out_pci_disable_device:
-	pci_disable_device(pdev);
-err_out_debugfs_del_dev:
-	ionic_debugfs_del_dev(ionic);
-err_out_clear_drvdata:
+	ionic_clear_pci(ionic);
+err_out:
 	mutex_destroy(&ionic->dev_cmd_lock);
 	ionic_devlink_free(ionic);
 
@@ -386,20 +403,71 @@ static void ionic_remove(struct pci_dev *pdev)
 	ionic_port_reset(ionic);
 	ionic_reset(ionic);
 	ionic_dev_teardown(ionic);
-	ionic_unmap_bars(ionic);
-	pci_release_regions(pdev);
-	pci_disable_device(pdev);
+	ionic_clear_pci(ionic);
 	ionic_debugfs_del_dev(ionic);
 	mutex_destroy(&ionic->dev_cmd_lock);
 	ionic_devlink_free(ionic);
 }
 
+static void ionic_reset_prepare(struct pci_dev *pdev)
+{
+	struct ionic *ionic = pci_get_drvdata(pdev);
+	struct ionic_lif *lif = ionic->lif;
+
+	dev_dbg(ionic->dev, "%s: device stopping\n", __func__);
+
+	del_timer_sync(&ionic->watchdog_timer);
+	cancel_work_sync(&lif->deferred.work);
+
+	mutex_lock(&lif->queue_lock);
+	ionic_stop_queues_reconfig(lif);
+	ionic_txrx_free(lif);
+	ionic_lif_deinit(lif);
+	ionic_qcqs_free(lif);
+	mutex_unlock(&lif->queue_lock);
+
+	ionic_dev_teardown(ionic);
+	ionic_clear_pci(ionic);
+	ionic_debugfs_del_dev(ionic);
+}
+
+static void ionic_reset_done(struct pci_dev *pdev)
+{
+	struct ionic *ionic = pci_get_drvdata(pdev);
+	struct ionic_lif *lif = ionic->lif;
+	int err;
+
+	err = ionic_setup_one(ionic);
+	if (err)
+		goto err_out;
+
+	ionic_debugfs_add_sizes(ionic);
+	ionic_debugfs_add_lif(ionic->lif);
+
+	err = ionic_restart_lif(lif);
+	if (err)
+		goto err_out;
+
+	mod_timer(&ionic->watchdog_timer, jiffies + 1);
+
+err_out:
+	dev_dbg(ionic->dev, "%s: device recovery %s\n",
+		__func__, err ? "failed" : "done");
+}
+
+static const struct pci_error_handlers ionic_err_handler = {
+	/* FLR handling */
+	.reset_prepare      = ionic_reset_prepare,
+	.reset_done         = ionic_reset_done,
+};
+
 static struct pci_driver ionic_driver = {
 	.name = IONIC_DRV_NAME,
 	.id_table = ionic_id_table,
 	.probe = ionic_probe,
 	.remove = ionic_remove,
 	.sriov_configure = ionic_sriov_configure,
+	.err_handler = &ionic_err_handler
 };
 
 int ionic_bus_register_driver(void)

drivers/net/ethernet/pensando/ionic/ionic_lif.c

@@ -434,7 +434,7 @@ static void ionic_qcq_free(struct ionic_lif *lif, struct ionic_qcq *qcq)
 	}
 }
 
-static void ionic_qcqs_free(struct ionic_lif *lif)
+void ionic_qcqs_free(struct ionic_lif *lif)
 {
 	struct device *dev = lif->ionic->dev;
 	struct ionic_qcq *adminqcq;
@@ -1754,7 +1754,7 @@ static int ionic_set_mac_address(struct net_device *netdev, void *sa)
 	return ionic_lif_addr_add(netdev_priv(netdev), mac);
 }
 
-static void ionic_stop_queues_reconfig(struct ionic_lif *lif)
+void ionic_stop_queues_reconfig(struct ionic_lif *lif)
 {
 	/* Stop and clean the queues before reconfiguration */
 	netif_device_detach(lif->netdev);
@@ -2009,7 +2009,7 @@ static void ionic_txrx_deinit(struct ionic_lif *lif)
 	}
 }
 
-static void ionic_txrx_free(struct ionic_lif *lif)
+void ionic_txrx_free(struct ionic_lif *lif)
 {
 	unsigned int i;
 
@@ -3266,27 +3266,11 @@ static void ionic_lif_handle_fw_down(struct ionic_lif *lif)
 	dev_info(ionic->dev, "FW Down: LIFs stopped\n");
 }
 
-static void ionic_lif_handle_fw_up(struct ionic_lif *lif)
+int ionic_restart_lif(struct ionic_lif *lif)
 {
 	struct ionic *ionic = lif->ionic;
 	int err;
 
-	if (!test_bit(IONIC_LIF_F_FW_RESET, lif->state))
-		return;
-
-	dev_info(ionic->dev, "FW Up: restarting LIFs\n");
-
-	ionic_init_devinfo(ionic);
-	err = ionic_identify(ionic);
-	if (err)
-		goto err_out;
-	err = ionic_port_identify(ionic);
-	if (err)
-		goto err_out;
-	err = ionic_port_init(ionic);
-	if (err)
-		goto err_out;
-
 	mutex_lock(&lif->queue_lock);
 
 	if (test_and_clear_bit(IONIC_LIF_F_BROKEN, lif->state))
@@ -3322,12 +3306,8 @@ static void ionic_lif_handle_fw_up(struct ionic_lif *lif)
 	clear_bit(IONIC_LIF_F_FW_RESET, lif->state);
 	ionic_link_status_check_request(lif, CAN_SLEEP);
 	netif_device_attach(lif->netdev);
-	dev_info(ionic->dev, "FW Up: LIFs restarted\n");
-
-	/* restore the hardware timestamping queues */
-	ionic_lif_hwstamp_replay(lif);
 
-	return;
+	return 0;
 
 err_txrx_free:
 	ionic_txrx_free(lif);
@@ -3337,6 +3317,46 @@ static void ionic_lif_handle_fw_up(struct ionic_lif *lif)
 	ionic_qcqs_free(lif);
 err_unlock:
 	mutex_unlock(&lif->queue_lock);
+
+	return err;
+}
+
+static void ionic_lif_handle_fw_up(struct ionic_lif *lif)
+{
+	struct ionic *ionic = lif->ionic;
+	int err;
+
+	if (!test_bit(IONIC_LIF_F_FW_RESET, lif->state))
+		return;
+
+	dev_info(ionic->dev, "FW Up: restarting LIFs\n");
+
+	/* This is a little different from what happens at
+	 * probe time because the LIF already exists so we
+	 * just need to reanimate it.
+	 */
+	ionic_init_devinfo(ionic);
+	err = ionic_identify(ionic);
+	if (err)
+		goto err_out;
+	err = ionic_port_identify(ionic);
+	if (err)
+		goto err_out;
+	err = ionic_port_init(ionic);
+	if (err)
+		goto err_out;
+
+	err = ionic_restart_lif(lif);
+	if (err)
+		goto err_out;
+
+	dev_info(ionic->dev, "FW Up: LIFs restarted\n");
+
+	/* restore the hardware timestamping queues */
+	ionic_lif_hwstamp_replay(lif);
+
+	return;
+
 err_out:
 	dev_err(ionic->dev, "FW Up: LIFs restart failed - err %d\n", err);
 }

drivers/net/ethernet/pensando/ionic/ionic_lif.h

@@ -325,6 +325,11 @@ void ionic_lif_deinit(struct ionic_lif *lif);
 int ionic_lif_addr_add(struct ionic_lif *lif, const u8 *addr);
 int ionic_lif_addr_del(struct ionic_lif *lif, const u8 *addr);
 
+void ionic_stop_queues_reconfig(struct ionic_lif *lif);
+void ionic_txrx_free(struct ionic_lif *lif);
+void ionic_qcqs_free(struct ionic_lif *lif);
+int ionic_restart_lif(struct ionic_lif *lif);
+
 int ionic_lif_register(struct ionic_lif *lif);
 void ionic_lif_unregister(struct ionic_lif *lif);
 int ionic_lif_identify(struct ionic *ionic, u8 lif_type,