[PATCH v4 2/4] uio_pci_generic: properly initialize PCI bars mappings towards UIO

[Vlad Zolotarov <vladz@cloudius-systems.com>]

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
---
 drivers/uio/uio_pci_generic.c | 89 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/drivers/uio/uio_pci_generic.c b/drivers/uio/uio_pci_generic.c
index d0b508b..2c6e2b1 100644
--- a/drivers/uio/uio_pci_generic.c
+++ b/drivers/uio/uio_pci_generic.c
@@ -40,6 +40,75 @@ to_uio_pci_generic_dev(struct uio_info *info)
 	return container_of(info, struct uio_pci_generic_dev, info);
 }
 
+/* Unmap previously ioremap'd resources */
+static void release_iomaps(struct uio_pci_generic_dev *gdev)
+{
+	int i;
+	struct uio_mem *mem = gdev->info.mem;
+
+	for (i = 0; i < MAX_UIO_MAPS; i++, mem++) {
+		if (mem->internal_addr) {
+			iounmap(mem->internal_addr);
+			mem->internal_addr = NULL;
+		}
+	}
+}
+
+static int setup_maps(struct pci_dev *pdev, struct uio_info *info)
+{
+	int i, m = 0, p = 0, err;
+	static const char * const bar_names[] = {
+		"BAR0",	"BAR1",	"BAR2",	"BAR3",	"BAR4",	"BAR5",
+	};
+
+	for (i = 0; i < ARRAY_SIZE(bar_names); i++) {
+		unsigned long start = pci_resource_start(pdev, i);
+		unsigned long flags = pci_resource_flags(pdev, i);
+		unsigned long len = pci_resource_len(pdev, i);
+
+		if (start == 0 || len == 0)
+			continue;
+
+		if (flags & IORESOURCE_MEM) {
+			void __iomem *addr;
+
+			if (m >= MAX_UIO_MAPS)
+				continue;
+
+			addr = ioremap(start, len);
+			if (addr == NULL) {
+				err = -EINVAL;
+				goto fail;
+			}
+
+			info->mem[m].name = bar_names[i];
+			info->mem[m].addr = start;
+			info->mem[m].internal_addr = addr;
+			info->mem[m].size = len;
+			info->mem[m].memtype = UIO_MEM_PHYS;
+			++m;
+		} else if (flags & IORESOURCE_IO) {
+			if (p >= MAX_UIO_PORT_REGIONS)
+				continue;
+
+			info->port[p].name = bar_names[i];
+			info->port[p].start = start;
+			info->port[p].size = len;
+			info->port[p].porttype = UIO_PORT_X86;
+			++p;
+		}
+	}
+
+	return 0;
+fail:
+	for (i = 0; i < m; i++) {
+		iounmap(info->mem[i].internal_addr);
+		info->mem[i].internal_addr = NULL;
+	}
+
+	return err;
+}
+
 /* Interrupt handler. Read/modify/write the command register to disable
  * the interrupt. */
 static irqreturn_t irqhandler(int irq, struct uio_info *info)
@@ -86,18 +155,35 @@ static int probe(struct pci_dev *pdev,
 
 	gdev->info.name = "uio_pci_generic";
 	gdev->info.version = DRIVER_VERSION;
+
+	err = pci_request_regions(pdev, "uio_pci_generic");
+	if (err != 0) {
+		dev_err(&pdev->dev, "Cannot request regions\n");
+		goto err_request_regions;
+	}
+
 	gdev->info.irq = pdev->irq;
 	gdev->info.irq_flags = IRQF_SHARED;
 	gdev->info.handler = irqhandler;
 	gdev->pdev = pdev;
 
+	/* remap resources */
+	err = setup_maps(pdev, &gdev->info);
+	if (err)
+		goto err_maps;
+
 	err = uio_register_device(&pdev->dev, &gdev->info);
 	if (err)
 		goto err_register;
 	pci_set_drvdata(pdev, gdev);
 
 	return 0;
+
 err_register:
+	release_iomaps(gdev);
+err_maps:
+	pci_release_regions(pdev);
+err_request_regions:
 	kfree(gdev);
 err_alloc:
 err_verify:
@@ -110,8 +196,11 @@ static void remove(struct pci_dev *pdev)
 	struct uio_pci_generic_dev *gdev = pci_get_drvdata(pdev);
 
 	uio_unregister_device(&gdev->info);
+	release_iomaps(gdev);
+	pci_release_regions(pdev);
 	pci_disable_device(pdev);
 	kfree(gdev);
+	pci_set_drvdata(pdev, NULL);
 }
 
 static struct pci_driver uio_pci_driver = {
-- 
2.1.0