Patch "NVMe: Don't unmap controller registers on reset" has been added to the 4.4-stable tree

@@ -2672,10 +2672,10 @@ static int nvme_dev_add(struct nvme_dev
 	return 0;
 }
 
-static int nvme_dev_map(struct nvme_dev *dev)
+static int nvme_pci_enable(struct nvme_dev *dev)
 {
 	u64 cap;
-	int bars, result = -ENOMEM;
+	int result = -ENOMEM;
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
 	if (pci_enable_device_mem(pdev))

@@ -2683,24 +2683,14 @@ static int nvme_dev_map(struct nvme_dev
 
 	dev->entry[0].vector = pdev->irq;
 	pci_set_master(pdev);
-	bars = pci_select_bars(pdev, IORESOURCE_MEM);
-	if (!bars)
-		goto disable_pci;
-
-	if (pci_request_selected_regions(pdev, bars, "nvme"))
-		goto disable_pci;
 
 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
 		goto disable;
 
-	dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
-	if (!dev->bar)
-		goto disable;
-
 	if (readl(&dev->bar->csts) == -1) {
 		result = -ENODEV;
-		goto unmap;
+		goto disable;
 	}
 
 	/*

@@ -2710,7 +2700,7 @@ static int nvme_dev_map(struct nvme_dev
 	if (!pdev->irq) {
 		result = pci_enable_msix(pdev, dev->entry, 1);
 		if (result < 0)
-			goto unmap;
+			goto disable;
 	}
 
 	cap = lo_hi_readq(&dev->bar->cap);

@@ -2734,18 +2724,21 @@ static int nvme_dev_map(struct nvme_dev
 
 	return 0;
 
- unmap:
-	iounmap(dev->bar);
-	dev->bar = NULL;
  disable:
 	pci_release_regions(pdev);
- disable_pci:
-	pci_disable_device(pdev);
+
 	return result;
 }
 
 static void nvme_dev_unmap(struct nvme_dev *dev)
 {
+	if (dev->bar)
+		iounmap(dev->bar);
+	pci_release_regions(to_pci_dev(dev->dev));
+}
+
+static void nvme_pci_disable(struct nvme_dev *dev)
+{
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
 	if (pdev->msi_enabled)

@@ -2753,12 +2746,6 @@ static void nvme_dev_unmap(struct nvme_d
 	else if (pdev->msix_enabled)
 		pci_disable_msix(pdev);
 
-	if (dev->bar) {
-		iounmap(dev->bar);
-		dev->bar = NULL;
-		pci_release_regions(pdev);
-	}
-
 	if (pci_is_enabled(pdev))
 		pci_disable_device(pdev);
 }

@@ -2962,7 +2949,7 @@ static void nvme_dev_shutdown(struct nvm
 
 	nvme_dev_list_remove(dev);
 
-	if (dev->bar) {
+	if (pci_is_enabled(to_pci_dev(dev->dev))) {
 		nvme_freeze_queues(dev);
 		csts = readl(&dev->bar->csts);
 	}

@@ -2976,7 +2963,7 @@ static void nvme_dev_shutdown(struct nvm
 		nvme_shutdown_ctrl(dev);
 		nvme_disable_queue(dev, 0);
 	}
-	nvme_dev_unmap(dev);
+	nvme_pci_disable(dev);
 
 	for (i = dev->queue_count - 1; i >= 0; i--)
 		nvme_clear_queue(dev->queues[i]);

@@ -3136,7 +3123,7 @@ static void nvme_probe_work(struct work_
 	bool start_thread = false;
 	int result;
 
-	result = nvme_dev_map(dev);
+	result = nvme_pci_enable(dev);
 	if (result)
 		goto out;
 

@@ -3292,6 +3279,27 @@ static ssize_t nvme_sysfs_reset(struct d
 }
 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
 
+static int nvme_dev_map(struct nvme_dev *dev)
+{
+	int bars;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	bars = pci_select_bars(pdev, IORESOURCE_MEM);
+	if (!bars)
+		return -ENODEV;
+	if (pci_request_selected_regions(pdev, bars, "nvme"))
+		return -ENODEV;
+
+	dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
+	if (!dev->bar)
+		goto release;
+
+	return 0;
+release:
+	pci_release_regions(pdev);
+	return -ENODEV;
+}
+
 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	int node, result = -ENOMEM;

@@ -3317,6 +3325,11 @@ static int nvme_probe(struct pci_dev *pd
 	INIT_WORK(&dev->reset_work, nvme_reset_work);
 	dev->dev = get_device(&pdev->dev);
 	pci_set_drvdata(pdev, dev);
+
+	result = nvme_dev_map(dev);
+	if (result)
+		goto free;
+
 	result = nvme_set_instance(dev);
 	if (result)
 		goto put_pci;

@@ -3355,6 +3368,7 @@ static int nvme_probe(struct pci_dev *pd
 	nvme_release_instance(dev);
  put_pci:
 	put_device(dev->dev);
+	nvme_dev_unmap(dev);
  free:
 	kfree(dev->queues);
 	kfree(dev->entry);

@@ -3398,6 +3412,7 @@ static void nvme_remove(struct pci_dev *
 	nvme_free_queues(dev, 0);
 	nvme_release_cmb(dev);
 	nvme_release_prp_pools(dev);
+	nvme_dev_unmap(dev);
 	kref_put(&dev->kref, nvme_free_dev);
 }