[PATCH 3/3] drivers:hv Remove old MMIO management code

[Jake Oshins <jakeo@microsoft.com>]

This patch removes the code that is no longer necessary
after the first two patches in this series have been applied.
It exposed a static range of memory-mapped I/O space gleaned
from the ACPI namespace, in a way that worked for a single
paravirtual device, the video frame buffer.

Signed-off-by: Jake Oshins <jakeo@microsoft.com>
---
 drivers/hv/vmbus_drv.c          | 25 -------------------------
 drivers/video/fbdev/hyperv_fb.c | 27 ++++++++++++++-------------
 include/linux/hyperv.h          |  2 --
 3 files changed, 14 insertions(+), 40 deletions(-)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 5d85ef3..2722e63 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -44,12 +44,6 @@ static struct tasklet_struct msg_dpc;
 static struct completion probe_event;
 static int irq;
 
-struct resource hyperv_mmio = {
-	.name  = "hyperv mmio",
-	.flags = IORESOURCE_MEM,
-};
-EXPORT_SYMBOL_GPL(hyperv_mmio);
-
 static int vmbus_exists(void)
 {
 	if (hv_acpi_dev == NULL)
@@ -555,7 +549,6 @@ static void vmbus_device_release(struct device *device)
 	kfree(hv_dev);
 }
 
-
 /* The one and only one */
 static struct bus_type  hv_bus = {
 	.name =		"vmbus",
@@ -931,11 +924,6 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
 	case ACPI_RESOURCE_TYPE_IRQ:
 		irq = res->data.irq.interrupts[0];
 		break;
-
-	case ACPI_RESOURCE_TYPE_ADDRESS64:
-		hyperv_mmio.start = res->data.address64.address.minimum;
-		hyperv_mmio.end = res->data.address64.address.maximum;
-		break;
 	}
 
 	return AE_OK;
@@ -953,20 +941,7 @@ static int vmbus_acpi_add(struct acpi_device *device)
 
 	if (ACPI_FAILURE(result))
 		goto acpi_walk_err;
-	/*
-	 * The parent of the vmbus acpi device (Gen2 firmware) is the VMOD that
-	 * has the mmio ranges. Get that.
-	 */
-	if (device->parent) {
-		result = acpi_walk_resources(device->parent->handle,
-					METHOD_NAME__CRS,
-					vmbus_walk_resources, NULL);
 
-		if (ACPI_FAILURE(result))
-			goto acpi_walk_err;
-		if (hyperv_mmio.start && hyperv_mmio.end)
-			request_resource(&iomem_resource, &hyperv_mmio);
-	}
 	ret_val = 0;
 
 acpi_walk_err:
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index 69ea59b..161157e 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -675,26 +675,22 @@ static void hvfb_get_option(struct fb_info *info)
 
 
 /* Get framebuffer memory from Hyper-V video pci space */
-static int hvfb_getmem(struct fb_info *info)
+static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
 {
 	struct hvfb_par *par = info->par;
 	struct pci_dev *pdev  = NULL;
 	void __iomem *fb_virt;
+	struct resource *res;
 	int gen2vm = efi_enabled(EFI_BOOT);
 	int ret;
 
-	par->mem.name = KBUILD_MODNAME;
-	par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 	if (gen2vm) {
-		ret = allocate_resource(&hyperv_mmio, &par->mem,
-					screen_fb_size,
-					0, -1,
-					screen_fb_size,
-					NULL, NULL);
-		if (ret != 0) {
-			pr_err("Unable to allocate framebuffer memory\n");
+		res = pnp_get_resource(hdev->pnp_dev, IORESOURCE_MEM, 0);
+		if (!res) {
+			pr_err("Unable to fetch FB claim\n");
 			return -ENODEV;
 		}
+		par->mem = *res;
 	} else {
 		pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
 			      PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
@@ -707,6 +703,8 @@ static int hvfb_getmem(struct fb_info *info)
 		    pci_resource_len(pdev, 0) < screen_fb_size)
 			goto err1;
 
+		par->mem.name = KBUILD_MODNAME;
+		par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 		par->mem.end = pci_resource_end(pdev, 0);
 		par->mem.start = par->mem.end - screen_fb_size + 1;
 		ret = request_resource(&pdev->resource[0], &par->mem);
@@ -747,7 +745,8 @@ static int hvfb_getmem(struct fb_info *info)
 err3:
 	iounmap(fb_virt);
 err2:
-	release_resource(&par->mem);
+	if (!gen2vm)
+		release_resource(&par->mem);
 err1:
 	if (!gen2vm)
 		pci_dev_put(pdev);
@@ -759,9 +758,11 @@ err1:
 static void hvfb_putmem(struct fb_info *info)
 {
 	struct hvfb_par *par = info->par;
+	int gen2vm = efi_enabled(EFI_BOOT);
 
 	iounmap(info->screen_base);
-	release_resource(&par->mem);
+	if (!gen2vm)
+		release_resource(&par->mem);
 }
 
 
@@ -792,7 +793,7 @@ static int hvfb_probe(struct hv_device *hdev,
 		goto error1;
 	}
 
-	ret = hvfb_getmem(info);
+	ret = hvfb_getmem(hdev, info);
 	if (ret) {
 		pr_err("No memory for framebuffer\n");
 		goto error2;
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 796cc32..993ea5f 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1221,8 +1221,6 @@ int hv_vss_init(struct hv_util_service *);
 void hv_vss_deinit(void);
 void hv_vss_onchannelcallback(void *);
 
-extern struct resource hyperv_mmio;
-
 /*
  * Negotiated version with the Host.
  */
-- 
1.9.1