PCI: Split ->reset_notify() method into ->reset_prepare() and ->reset_done()

The pci_error_handlers->reset_notify() method had a flag to indicate
whether to prepare for or clean up after a reset.  The prepare and done
cases have no shared functionality whatsoever, so split them into separate
methods.

[bhelgaas: changelog, update locking comments]
Link: http://lkml.kernel.org/r/20170601111039.8913-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/net/ethernet/intel/fm10k/fm10k_pci.c

@@ -2348,30 +2348,19 @@ static void fm10k_io_resume(struct pci_dev *pdev)
 		netif_device_attach(netdev);
 }
 
-/**
- * fm10k_io_reset_notify - called when PCI function is reset
- * @pdev: Pointer to PCI device
- *
- * This callback is called when the PCI function is reset such as from
- * /sys/class/net/<enpX>/device/reset or similar. When prepare is true, it
- * means we should prepare for a function reset. If prepare is false, it means
- * the function reset just occurred.
- */
-static void fm10k_io_reset_notify(struct pci_dev *pdev, bool prepare)
+static void fm10k_io_reset_prepare(struct pci_dev *pdev)
 {
-	struct fm10k_intfc *interface = pci_get_drvdata(pdev);
-	int err = 0;
-
-	if (prepare) {
-		/* warn incase we have any active VF devices */
-		if (pci_num_vf(pdev))
-			dev_warn(&pdev->dev,
-				 "PCIe FLR may cause issues for any active VF devices\n");
+	/* warn incase we have any active VF devices */
+	if (pci_num_vf(pdev))
+		dev_warn(&pdev->dev,
+			 "PCIe FLR may cause issues for any active VF devices\n");
+	fm10k_prepare_suspend(pci_get_drvdata(pdev));
+}
 
-		fm10k_prepare_suspend(interface);
-	} else {
-		err = fm10k_handle_resume(interface);
-	}
+static void fm10k_io_reset_done(struct pci_dev *pdev)
+{
+	struct fm10k_intfc *interface = pci_get_drvdata(pdev);
+	int err = fm10k_handle_resume(interface);
 
 	if (err) {
 		dev_warn(&pdev->dev,
@@ -2384,7 +2373,8 @@ static const struct pci_error_handlers fm10k_err_handler = {
 	.error_detected = fm10k_io_error_detected,
 	.slot_reset = fm10k_io_slot_reset,
 	.resume = fm10k_io_resume,
-	.reset_notify = fm10k_io_reset_notify,
+	.reset_prepare = fm10k_io_reset_prepare,
+	.reset_done = fm10k_io_reset_done,
 };
 
 static struct pci_driver fm10k_driver = {

drivers/net/wireless/marvell/mwifiex/pcie.c

@@ -346,11 +346,13 @@ static const struct pci_device_id mwifiex_ids[] = {
 
 MODULE_DEVICE_TABLE(pci, mwifiex_ids);
 
-static void mwifiex_pcie_reset_notify(struct pci_dev *pdev, bool prepare)
+/*
+ * Cleanup all software without cleaning anything related to PCIe and HW.
+ */
+static void mwifiex_pcie_reset_prepare(struct pci_dev *pdev)
 {
 	struct pcie_service_card *card = pci_get_drvdata(pdev);
 	struct mwifiex_adapter *adapter = card->adapter;
-	int ret;
 
 	if (!adapter) {
 		dev_err(&pdev->dev, "%s: adapter structure is not valid\n",
@@ -359,37 +361,48 @@ static void mwifiex_pcie_reset_notify(struct pci_dev *pdev, bool prepare)
 	}
 
 	mwifiex_dbg(adapter, INFO,
-		    "%s: vendor=0x%4.04x device=0x%4.04x rev=%d %s\n",
-		    __func__, pdev->vendor, pdev->device,
-		    pdev->revision,
-		    prepare ? "Pre-FLR" : "Post-FLR");
-
-	if (prepare) {
-		/* Kernel would be performing FLR after this notification.
-		 * Cleanup all software without cleaning anything related to
-		 * PCIe and HW.
-		 */
-		mwifiex_shutdown_sw(adapter);
-		adapter->surprise_removed = true;
-		clear_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags);
-		clear_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags);
-	} else {
-		/* Kernel stores and restores PCIe function context before and
-		 * after performing FLR respectively. Reconfigure the software
-		 * and firmware including firmware redownload
-		 */
-		adapter->surprise_removed = false;
-		ret = mwifiex_reinit_sw(adapter);
-		if (ret) {
-			dev_err(&pdev->dev, "reinit failed: %d\n", ret);
-			return;
-		}
-	}
+		    "%s: vendor=0x%4.04x device=0x%4.04x rev=%d Pre-FLR\n",
+		    __func__, pdev->vendor, pdev->device, pdev->revision);
+
+	mwifiex_shutdown_sw(adapter);
+	adapter->surprise_removed = true;
+	clear_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags);
+	clear_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags);
 	mwifiex_dbg(adapter, INFO, "%s, successful\n", __func__);
 }
 
-static const struct pci_error_handlers mwifiex_pcie_err_handler[] = {
-		{ .reset_notify = mwifiex_pcie_reset_notify, },
+/*
+ * Kernel stores and restores PCIe function context before and after performing
+ * FLR respectively. Reconfigure the software and firmware including firmware
+ * redownload.
+ */
+static void mwifiex_pcie_reset_done(struct pci_dev *pdev)
+{
+	struct pcie_service_card *card = pci_get_drvdata(pdev);
+	struct mwifiex_adapter *adapter = card->adapter;
+	int ret;
+
+	if (!adapter) {
+		dev_err(&pdev->dev, "%s: adapter structure is not valid\n",
+			__func__);
+		return;
+	}
+
+	mwifiex_dbg(adapter, INFO,
+		    "%s: vendor=0x%4.04x device=0x%4.04x rev=%d Post-FLR\n",
+		    __func__, pdev->vendor, pdev->device, pdev->revision);
+
+	adapter->surprise_removed = false;
+	ret = mwifiex_reinit_sw(adapter);
+	if (ret)
+		dev_err(&pdev->dev, "reinit failed: %d\n", ret);
+	else
+		mwifiex_dbg(adapter, INFO, "%s, successful\n", __func__);
+}
+
+static const struct pci_error_handlers mwifiex_pcie_err_handler = {
+	.reset_prepare		= mwifiex_pcie_reset_prepare,
+	.reset_done		= mwifiex_pcie_reset_done,
 };
 
 #ifdef CONFIG_PM_SLEEP
@@ -410,7 +423,7 @@ static struct pci_driver __refdata mwifiex_pcie = {
 	},
 #endif
 	.shutdown = mwifiex_pcie_shutdown,
-	.err_handler = mwifiex_pcie_err_handler,
+	.err_handler = &mwifiex_pcie_err_handler,
 };
 
 /*

drivers/nvme/host/pci.c

@@ -2145,14 +2145,14 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	return result;
 }
 
-static void nvme_reset_notify(struct pci_dev *pdev, bool prepare)
+static void nvme_reset_prepare(struct pci_dev *pdev)
 {
-	struct nvme_dev *dev = pci_get_drvdata(pdev);
+	nvme_dev_disable(pci_get_drvdata(pdev), false);
+}
 
-	if (prepare)
-		nvme_dev_disable(dev, false);
-	else
-		nvme_reset(dev);
+static void nvme_reset_done(struct pci_dev *pdev)
+{
+	nvme_reset(pci_get_drvdata(pdev));
 }
 
 static void nvme_shutdown(struct pci_dev *pdev)
@@ -2275,7 +2275,8 @@ static const struct pci_error_handlers nvme_err_handler = {
 	.error_detected	= nvme_error_detected,
 	.slot_reset	= nvme_slot_reset,
 	.resume		= nvme_error_resume,
-	.reset_notify	= nvme_reset_notify,
+	.reset_prepare	= nvme_reset_prepare,
+	.reset_done	= nvme_reset_done,
 };
 
 static const struct pci_device_id nvme_id_table[] = {

drivers/pci/pci.c

@@ -4130,32 +4130,18 @@ static void pci_dev_unlock(struct pci_dev *dev)
 	pci_cfg_access_unlock(dev);
 }
 
-/**
- * pci_reset_notify - notify device driver of reset
- * @dev: device to be notified of reset
- * @prepare: 'true' if device is about to be reset; 'false' if reset attempt
- *           completed
- *
- * Must be called prior to device access being disabled and after device
- * access is restored.
- */
-static void pci_reset_notify(struct pci_dev *dev, bool prepare)
+static void pci_dev_save_and_disable(struct pci_dev *dev)
 {
 	const struct pci_error_handlers *err_handler =
 			dev->driver ? dev->driver->err_handler : NULL;
 
 	/*
-	 * dev->driver->err_handler->reset_notify() is protected against
+	 * dev->driver->err_handler->reset_prepare() is protected against
 	 * races with ->remove() by the device lock, which must be held by
 	 * the caller.
 	 */
-	if (err_handler && err_handler->reset_notify)
-		err_handler->reset_notify(dev, prepare);
-}
-
-static void pci_dev_save_and_disable(struct pci_dev *dev)
-{
-	pci_reset_notify(dev, true);
+	if (err_handler && err_handler->reset_prepare)
+		err_handler->reset_prepare(dev);
 
 	/*
 	 * Wake-up device prior to save.  PM registers default to D0 after
@@ -4177,8 +4163,18 @@ static void pci_dev_save_and_disable(struct pci_dev *dev)
 
 static void pci_dev_restore(struct pci_dev *dev)
 {
+	const struct pci_error_handlers *err_handler =
+			dev->driver ? dev->driver->err_handler : NULL;
+
 	pci_restore_state(dev);
-	pci_reset_notify(dev, false);
+
+	/*
+	 * dev->driver->err_handler->reset_done() is protected against
+	 * races with ->remove() by the device lock, which must be held by
+	 * the caller.
+	 */
+	if (err_handler && err_handler->reset_done)
+		err_handler->reset_done(dev);
 }
 
 static int pci_dev_reset(struct pci_dev *dev, int probe)

include/linux/pci.h

@@ -698,7 +698,8 @@ struct pci_error_handlers {
 	pci_ers_result_t (*slot_reset)(struct pci_dev *dev);
 
 	/* PCI function reset prepare or completed */
-	void (*reset_notify)(struct pci_dev *dev, bool prepare);
+	void (*reset_prepare)(struct pci_dev *dev);
+	void (*reset_done)(struct pci_dev *dev);
 
 	/* Device driver may resume normal operations */
 	void (*resume)(struct pci_dev *dev);