Consolidate ACPI PCI root common code into ACPI core

index 15d22db05054..cdc5c2599beb 100644
@@ -119,7 +119,7 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res)
 EXPORT_SYMBOL_GPL(acpi_dev_resource_memory);
 
 static void acpi_dev_ioresource_flags(struct resource *res, u64 len,
-				      u8 io_decode)
+				      u8 io_decode, u8 translation_type)
 {
 	res->flags = IORESOURCE_IO;
 

@@ -131,6 +131,8 @@ static void acpi_dev_ioresource_flags(struct resource *res, u64 len,
 
 	if (io_decode == ACPI_DECODE_16)
 		res->flags |= IORESOURCE_IO_16BIT_ADDR;
+	if (translation_type == ACPI_SPARSE_TRANSLATION)
+		res->flags |= IORESOURCE_IO_SPARSE;
 }
 
 static void acpi_dev_get_ioresource(struct resource *res, u64 start, u64 len,

@@ -138,7 +140,7 @@ static void acpi_dev_get_ioresource(struct resource *res, u64 start, u64 len,
 {
 	res->start = start;
 	res->end = start + len - 1;
-	acpi_dev_ioresource_flags(res, len, io_decode);
+	acpi_dev_ioresource_flags(res, len, io_decode, 0);
 }
 
 /**

@@ -231,7 +233,8 @@ static bool acpi_decode_space(struct resource_win *win,
 		acpi_dev_memresource_flags(res, len, wp);
 		break;
 	case ACPI_IO_RANGE:
-		acpi_dev_ioresource_flags(res, len, iodec);
+		acpi_dev_ioresource_flags(res, len, iodec,
+					  addr->info.io.translation_type);
 		break;
 	case ACPI_BUS_NUMBER_RANGE:
 		res->flags = IORESOURCE_BUS;

index 388e3ae94f7a..24bea087e7af 100644
@@ -94,6 +94,7 @@ struct resource {
 /* PnP I/O specific bits (IORESOURCE_BITS) */
 #define IORESOURCE_IO_16BIT_ADDR	(1<<0)
 #define IORESOURCE_IO_FIXED		(1<<1)
+#define IORESOURCE_IO_SPARSE		(1<<2)
 
 /* PCI ROM control bits (IORESOURCE_BITS) */
 #define IORESOURCE_ROM_ENABLE		(1<<0)	/* ROM is enabled, same as PCI_ROM_ADDRESS_ENABLE */

index d89b6013c941..d092c6b08666 100644
@@ -115,29 +115,12 @@ struct pci_ops pci_root_ops = {
 	.write = pci_write,
 };
 
-/* Called by ACPI when it finds a new root bus.  */
-
-static struct pci_controller *alloc_pci_controller(int seg)
-{
-	struct pci_controller *controller;
-
-	controller = kzalloc(sizeof(*controller), GFP_KERNEL);
-	if (!controller)
-		return NULL;
-
-	controller->segment = seg;
-	return controller;
-}
-
 struct pci_root_info {
+	struct pci_controller controller;
 	struct acpi_device *bridge;
-	struct pci_controller *controller;
 	struct list_head resources;
-	struct resource *res;
-	resource_size_t *res_offset;
-	unsigned int res_num;
 	struct list_head io_resources;
-	char *name;
+	char name[16];
 };
 
 static unsigned int

@@ -168,11 +151,11 @@ new_space (u64 phys_base, int sparse)
 	return i;
 }
 
-static u64 add_io_space(struct pci_root_info *info,
-			struct acpi_resource_address64 *addr)
+static int add_io_space(struct device *dev, struct pci_root_info *info,
+			struct resource_entry *entry)
 {
 	struct iospace_resource *iospace;
-	struct resource *resource;
+	struct resource *resource, *res = entry->res;
 	char *name;
 	unsigned long base, min, max, base_port;
 	unsigned int sparse = 0, space_nr, len;

@@ -180,27 +163,24 @@ static u64 add_io_space(struct pci_root_info *info,
 	len = strlen(info->name) + 32;
 	iospace = kzalloc(sizeof(*iospace) + len, GFP_KERNEL);
 	if (!iospace) {
-		dev_err(&info->bridge->dev,
-				"PCI: No memory for %s I/O port space\n",
-				info->name);
-		goto out;
+		dev_err(dev, "PCI: No memory for %s I/O port space\n",
+			info->name);
+		return -ENOMEM;
 	}
 
-	name = (char *)(iospace + 1);
-
-	min = addr->address.minimum;
-	max = min + addr->address.address_length - 1;
-	if (addr->info.io.translation_type == ACPI_SPARSE_TRANSLATION)
+	if (res->flags & IORESOURCE_IO_SPARSE)
 		sparse = 1;
-
-	space_nr = new_space(addr->address.translation_offset, sparse);
+	space_nr = new_space(entry->offset, sparse);
 	if (space_nr == ~0)
 		goto free_resource;
 
+	name = (char *)(iospace + 1);
+	min = res->start - entry->offset;
+	max = res->end - entry->offset;
 	base = __pa(io_space[space_nr].mmio_base);
 	base_port = IO_SPACE_BASE(space_nr);
 	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->name,
-		base_port + min, base_port + max);
+		 base_port + min, base_port + max);
 
 	/*
 	 * The SDM guarantees the legacy 0-64K space is sparse, but if the

@@ -216,153 +196,195 @@ static u64 add_io_space(struct pci_root_info *info,
 	resource->start = base + (sparse ? IO_SPACE_SPARSE_ENCODING(min) : min);
 	resource->end   = base + (sparse ? IO_SPACE_SPARSE_ENCODING(max) : max);
 	if (insert_resource(&iomem_resource, resource)) {
-		dev_err(&info->bridge->dev,
-				"can't allocate host bridge io space resource  %pR\n",
-				resource);
+		dev_err(dev,
+			"can't allocate host bridge io space resource  %pR\n",
+			resource);
 		goto free_resource;
 	}
 
+	entry->offset = base_port;
+	res->start = min + base_port;
+	res->end = max + base_port;
 	list_add_tail(&iospace->list, &info->io_resources);
-	return base_port;
+
+	return 0;
 
 free_resource:
 	kfree(iospace);
-out:
-	return ~0;
+	return -ENOSPC;
+}
+
+/*
+ * An IO port or MMIO resource assigned to a PCI host bridge may be
+ * consumed by the host bridge itself or available to its child
+ * bus/devices. The ACPI specification defines a bit (Producer/Consumer)
+ * to tell whether the resource is consumed by the host bridge itself,
+ * but firmware hasn't used that bit consistently, so we can't rely on it.
+ *
+ * On x86 and IA64 platforms, all IO port and MMIO resources are assumed
+ * to be available to child bus/devices except one special case:
+ *     IO port [0xCF8-0xCFF] is consumed by the host bridge itself
+ *     to access PCI configuration space.
+ *
+ * So explicitly filter out PCI CFG IO ports[0xCF8-0xCFF].
+ */
+static bool resource_is_pcicfg_ioport(struct resource *res)
+{
+	return (res->flags & IORESOURCE_IO) &&
+		res->start == 0xCF8 && res->end == 0xCFF;
 }
 
-static acpi_status resource_to_window(struct acpi_resource *resource,
-				      struct acpi_resource_address64 *addr)
+static int
+probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
+		    int busnum, int domain)
 {
-	acpi_status status;
+	int ret;
+	struct list_head *list = &info->resources;
+	struct resource_entry *entry, *tmp;
 
-	/*
-	 * We're only interested in _CRS descriptors that are
-	 *	- address space descriptors for memory or I/O space
-	 *	- non-zero size
-	 */
-	status = acpi_resource_to_address64(resource, addr);
-	if (ACPI_SUCCESS(status) &&
-	    (addr->resource_type == ACPI_MEMORY_RANGE ||
-	     addr->resource_type == ACPI_IO_RANGE) &&
-	    addr->address.address_length)
-		return AE_OK;
-
-	return AE_ERROR;
-}
-
-static acpi_status count_window(struct acpi_resource *resource, void *data)
-{
-	unsigned int *windows = (unsigned int *) data;
-	struct acpi_resource_address64 addr;
-	acpi_status status;
-
-	status = resource_to_window(resource, &addr);
-	if (ACPI_SUCCESS(status))
-		(*windows)++;
-
-	return AE_OK;
-}
-
-static acpi_status add_window(struct acpi_resource *res, void *data)
-{
-	struct pci_root_info *info = data;
-	struct resource *resource;
-	struct acpi_resource_address64 addr;
-	acpi_status status;
-	unsigned long flags, offset = 0;
-	struct resource *root;
-
-	/* Return AE_OK for non-window resources to keep scanning for more */
-	status = resource_to_window(res, &addr);
-	if (!ACPI_SUCCESS(status))
-		return AE_OK;
-
-	if (addr.resource_type == ACPI_MEMORY_RANGE) {
-		flags = IORESOURCE_MEM;
-		root = &iomem_resource;
-		offset = addr.address.translation_offset;
-	} else if (addr.resource_type == ACPI_IO_RANGE) {
-		flags = IORESOURCE_IO;
-		root = &ioport_resource;
-		offset = add_io_space(info, &addr);
-		if (offset == ~0)
-			return AE_OK;
-	} else
-		return AE_OK;
-
-	resource = &info->res[info->res_num];
-	resource->name = info->name;
-	resource->flags = flags;
-	resource->start = addr.address.minimum + offset;
-	resource->end = resource->start + addr.address.address_length - 1;
-	info->res_offset[info->res_num] = offset;
-
-	if (insert_resource(root, resource)) {
-		dev_err(&info->bridge->dev,
-			"can't allocate host bridge window %pR\n",
-			resource);
-	} else {
-		if (offset)
-			dev_info(&info->bridge->dev, "host bridge window %pR "
-				 "(PCI address [%#llx-%#llx])\n",
-				 resource,
-				 resource->start - offset,
-				 resource->end - offset);
-		else
-			dev_info(&info->bridge->dev,
-				 "host bridge window %pR\n", resource);
-	}
-	/* HP's firmware has a hack to work around a Windows bug.
-	 * Ignore these tiny memory ranges */
-	if (!((resource->flags & IORESOURCE_MEM) &&
-	      (resource->end - resource->start < 16)))
-		pci_add_resource_offset(&info->resources, resource,
-					info->res_offset[info->res_num]);
+	ret = acpi_dev_get_resources(device, list,
+				     acpi_dev_filter_resource_type_cb,
+				     (void *)(IORESOURCE_IO | IORESOURCE_MEM));
+	if (ret < 0)
+		dev_warn(&device->dev,
+			 "failed to parse _CRS method, error code %d\n", ret);
+	else if (ret == 0)
+		dev_dbg(&device->dev,
+			"no IO and memory resources present in _CRS\n");
+	else
+		resource_list_for_each_entry_safe(entry, tmp, list) {
+			if ((entry->res->flags & IORESOURCE_DISABLED) ||
+			    resource_is_pcicfg_ioport(entry->res))
+				resource_list_destroy_entry(entry);
+			else
+				entry->res->name = info->name;
+		}
 
-	info->res_num++;
-	return AE_OK;
+	return ret;
 }
 
-static void free_pci_root_info_res(struct pci_root_info *info)
-{
-	struct iospace_resource *iospace, *tmp;
+static void validate_resources(struct device *dev, struct list_head *resources,
+			       unsigned long type)
+{
+	LIST_HEAD(list);
+	struct resource *res1, *res2, *root = NULL;
+	struct resource_entry *tmp, *entry, *entry2;
+
+	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
+	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
+
+	list_splice_init(resources, &list);
+	resource_list_for_each_entry_safe(entry, tmp, &list) {
+		bool free = false;
+		resource_size_t end;
+
+		res1 = entry->res;
+		if (!(res1->flags & type))
+			goto next;
+
+		/* Exclude non-addressable range or non-addressable portion */
+		end = min(res1->end, root->end);
+		if (end <= res1->start) {
+			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
+				 res1);
+			free = true;
+			goto next;
+		} else if (res1->end != end) {
+			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
+				 res1, (unsigned long long)end + 1,
+				 (unsigned long long)res1->end);
+			res1->end = end;
+		}
 
-	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list)
-		kfree(iospace);
+		resource_list_for_each_entry(entry2, resources) {
+			res2 = entry2->res;
+			if (!(res2->flags & type))
+				continue;
+
+			/*
+			 * I don't like throwing away windows because then
+			 * our resources no longer match the ACPI _CRS, but
+			 * the kernel resource tree doesn't allow overlaps.
+			 */
+			if (resource_overlaps(res1, res2)) {
+				res2->start = min(res1->start, res2->start);
+				res2->end = max(res1->end, res2->end);
+				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
+					 res2, res1);
+				free = true;
+				goto next;
+			}
+		}
 
-	kfree(info->name);
-	kfree(info->res);
-	info->res = NULL;
-	kfree(info->res_offset);
-	info->res_offset = NULL;
-	info->res_num = 0;
-	kfree(info->controller);
-	info->controller = NULL;
+next:
+		resource_list_del(entry);
+		if (free)
+			resource_list_free_entry(entry);
+		else
+			resource_list_add_tail(entry, resources);
+	}
+}
+
+static void add_resources(struct pci_root_info *info, struct device *dev)
+{
+	struct resource_entry *entry, *tmp;
+	struct resource *res, *conflict, *root = NULL;
+	struct list_head *list = &info->resources;
+
+	validate_resources(dev, list, IORESOURCE_MEM);
+	validate_resources(dev, list, IORESOURCE_IO);
+
+	resource_list_for_each_entry_safe(entry, tmp, list) {
+		res = entry->res;
+		if (res->flags & IORESOURCE_MEM) {
+			root = &iomem_resource;
+			/*
+			 * HP's firmware has a hack to work around a Windows
+			 * bug. Ignore these tiny memory ranges.
+			 */
+			if (resource_size(res) <= 16) {
+				resource_list_destroy_entry(entry);
+				continue;
+			}
+		} else if (res->flags & IORESOURCE_IO) {
+			root = &ioport_resource;
+			if (add_io_space(&info->bridge->dev, info, entry)) {
+				resource_list_destroy_entry(entry);
+				continue;
+			}
+		} else {
+			BUG_ON(res);
+		}
+
+		conflict = insert_resource_conflict(root, res);
+		if (conflict) {
+			dev_info(dev,
+				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
+				 res, conflict->name, conflict);
+			resource_list_destroy_entry(entry);
+		}
+	}
 }
 
 static void __release_pci_root_info(struct pci_root_info *info)
 {
-	int i;
 	struct resource *res;
-	struct iospace_resource *iospace;
+	struct iospace_resource *iospace, *tmp;
+	struct resource_entry *entry, *tentry;
 
-	list_for_each_entry(iospace, &info->io_resources, list)
+	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list) {
 		release_resource(&iospace->res);
+		kfree(iospace);
+	}
 
-	for (i = 0; i < info->res_num; i++) {
-		res = &info->res[i];
-
-		if (!res->parent)
-			continue;
-
-		if (!(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
-			continue;
-
-		release_resource(res);
+	resource_list_for_each_entry_safe(entry, tentry, &info->resources) {
+		res = entry->res;
+		if (res->parent &&
+		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+			release_resource(res);
+		resource_list_destroy_entry(entry);
 	}
 
-	free_pci_root_info_res(info);
 	kfree(info);
 }
 

@@ -373,99 +395,49 @@ static void release_pci_root_info(struct pci_host_bridge *bridge)
 	__release_pci_root_info(info);
 }
 
-static int
-probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
-		int busnum, int domain)
-{
-	char *name;
-
-	name = kmalloc(16, GFP_KERNEL);
-	if (!name)
-		return -ENOMEM;
-
-	sprintf(name, "PCI Bus %04x:%02x", domain, busnum);
-	info->bridge = device;
-	info->name = name;
-
-	acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_window,
-			&info->res_num);
-	if (info->res_num) {
-		info->res =
-			kzalloc_node(sizeof(*info->res) * info->res_num,
-				     GFP_KERNEL, info->controller->node);
-		if (!info->res) {
-			kfree(name);
-			return -ENOMEM;
-		}
-
-		info->res_offset =
-			kzalloc_node(sizeof(*info->res_offset) * info->res_num,
-					GFP_KERNEL, info->controller->node);
-		if (!info->res_offset) {
-			kfree(name);
-			kfree(info->res);
-			info->res = NULL;
-			return -ENOMEM;
-		}
-
-		info->res_num = 0;
-		acpi_walk_resources(device->handle, METHOD_NAME__CRS,
-			add_window, info);
-	} else
-		kfree(name);
-
-	return 0;
-}
-
 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 {
 	struct acpi_device *device = root->device;
 	int domain = root->segment;
 	int bus = root->secondary.start;
-	struct pci_controller *controller;
-	struct pci_root_info *info = NULL;
-	int busnum = root->secondary.start;
+	struct pci_root_info *info;
 	struct pci_bus *pbus;
 	int ret;
 
-	controller = alloc_pci_controller(domain);
-	if (!controller)
-		return NULL;
-
-	controller->companion = device;
-	controller->node = acpi_get_node(device->handle);
-
 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (!info) {
 		dev_err(&device->dev,
-				"pci_bus %04x:%02x: ignored (out of memory)\n",
-				domain, busnum);
-		kfree(controller);
+			"pci_bus %04x:%02x: ignored (out of memory)\n",
+			domain, bus);
 		return NULL;
 	}
 
-	info->controller = controller;
-	INIT_LIST_HEAD(&info->io_resources);
+	info->controller.segment = domain;
+	info->controller.companion = device;
+	info->controller.node = acpi_get_node(device->handle);
+	info->bridge = device;
 	INIT_LIST_HEAD(&info->resources);
+	INIT_LIST_HEAD(&info->io_resources);
+	snprintf(info->name, sizeof(info->name),
+		 "PCI Bus %04x:%02x", domain, bus);
 
-	ret = probe_pci_root_info(info, device, busnum, domain);
-	if (ret) {
-		kfree(info->controller);
+	ret = probe_pci_root_info(info, device, bus, domain);
+	if (ret <= 0) {
 		kfree(info);
 		return NULL;
 	}
-	/* insert busn resource at first */
+	add_resources(info, &info->bridge->dev);
 	pci_add_resource(&info->resources, &root->secondary);
+
 	/*
 	 * See arch/x86/pci/acpi.c.
 	 * The desired pci bus might already be scanned in a quirk. We
 	 * should handle the case here, but it appears that IA64 hasn't
 	 * such quirk. So we just ignore the case now.
 	 */
-	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops, controller,
-				   &info->resources);
+	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops,
+				   &info->controller, &info->resources);
 	if (!pbus) {
-		pci_free_resource_list(&info->resources);
 		__release_pci_root_info(info);
 		return NULL;
 	}

index 36d2c1e3928b..07039d168f37 100644
@@ -64,11 +64,6 @@ extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
 #define pci_legacy_read platform_pci_legacy_read
 #define pci_legacy_write platform_pci_legacy_write
 
-struct iospace_resource {
-	struct list_head list;
-	struct resource res;
-};
-
 struct pci_controller {
 	struct acpi_device *companion;
 	void *iommu;

index d092c6b08666..5dd3753a2739 100644
@@ -154,14 +154,14 @@ new_space (u64 phys_base, int sparse)
 static int add_io_space(struct device *dev, struct pci_root_info *info,
 			struct resource_entry *entry)
 {
-	struct iospace_resource *iospace;
+	struct resource_entry *iospace;
 	struct resource *resource, *res = entry->res;
 	char *name;
 	unsigned long base, min, max, base_port;
 	unsigned int sparse = 0, space_nr, len;
 
 	len = strlen(info->name) + 32;
-	iospace = kzalloc(sizeof(*iospace) + len, GFP_KERNEL);
+	iospace = resource_list_create_entry(NULL, len);
 	if (!iospace) {
 		dev_err(dev, "PCI: No memory for %s I/O port space\n",
 			info->name);

@@ -190,7 +190,7 @@ static int add_io_space(struct device *dev, struct pci_root_info *info,
 	if (space_nr == 0)
 		sparse = 1;
 
-	resource = &iospace->res;
+	resource = iospace->res;
 	resource->name  = name;
 	resource->flags = IORESOURCE_MEM;
 	resource->start = base + (sparse ? IO_SPACE_SPARSE_ENCODING(min) : min);

@@ -205,12 +205,12 @@ static int add_io_space(struct device *dev, struct pci_root_info *info,
 	entry->offset = base_port;
 	res->start = min + base_port;
 	res->end = max + base_port;
-	list_add_tail(&iospace->list, &info->io_resources);
+	resource_list_add_tail(iospace, &info->io_resources);
 
 	return 0;
 
 free_resource:
-	kfree(iospace);
+	resource_list_free_entry(iospace);
 	return -ENOSPC;
 }
 

@@ -369,12 +369,11 @@ static void add_resources(struct pci_root_info *info, struct device *dev)
 static void __release_pci_root_info(struct pci_root_info *info)
 {
 	struct resource *res;
-	struct iospace_resource *iospace, *tmp;
 	struct resource_entry *entry, *tentry;
 
-	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list) {
-		release_resource(&iospace->res);
-		kfree(iospace);
+	resource_list_for_each_entry_safe(entry, tentry, &info->io_resources) {
+		release_resource(entry->res);
+		resource_list_destroy_entry(entry);
 	}
 
 	resource_list_for_each_entry_safe(entry, tentry, &info->resources) {

index 393706a5261b..48d27bd35b58 100644
@@ -652,6 +652,210 @@ static void acpi_pci_root_remove(struct acpi_device *device)
 	kfree(root);
 }
 
+/*
+ * Following code to support acpi_pci_root_create() is copied from
+ * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
+ * and ARM64.
+ */
+static void acpi_pci_root_validate_resources(struct device *dev,
+					     struct list_head *resources,
+					     unsigned long type)
+{
+	LIST_HEAD(list);
+	struct resource *res1, *res2, *root = NULL;
+	struct resource_entry *tmp, *entry, *entry2;
+
+	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
+	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
+
+	list_splice_init(resources, &list);
+	resource_list_for_each_entry_safe(entry, tmp, &list) {
+		bool free = false;
+		resource_size_t end;
+
+		res1 = entry->res;
+		if (!(res1->flags & type))
+			goto next;
+
+		/* Exclude non-addressable range or non-addressable portion */
+		end = min(res1->end, root->end);
+		if (end <= res1->start) {
+			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
+				 res1);
+			free = true;
+			goto next;
+		} else if (res1->end != end) {
+			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
+				 res1, (unsigned long long)end + 1,
+				 (unsigned long long)res1->end);
+			res1->end = end;
+		}
+
+		resource_list_for_each_entry(entry2, resources) {
+			res2 = entry2->res;
+			if (!(res2->flags & type))
+				continue;
+
+			/*
+			 * I don't like throwing away windows because then
+			 * our resources no longer match the ACPI _CRS, but
+			 * the kernel resource tree doesn't allow overlaps.
+			 */
+			if (resource_overlaps(res1, res2)) {
+				res2->start = min(res1->start, res2->start);
+				res2->end = max(res1->end, res2->end);
+				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
+					 res2, res1);
+				free = true;
+				goto next;
+			}
+		}
+
+next:
+		resource_list_del(entry);
+		if (free)
+			resource_list_free_entry(entry);
+		else
+			resource_list_add_tail(entry, resources);
+	}
+}
+
+static int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
+{
+	int ret;
+	struct list_head *list = &info->resources;
+	struct acpi_device *device = info->bridge;
+	struct resource_entry *entry, *tmp;
+	unsigned long flags;
+
+	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
+	ret = acpi_dev_get_resources(device, list,
+				     acpi_dev_filter_resource_type_cb,
+				     (void *)flags);
+	if (ret < 0)
+		dev_warn(&device->dev,
+			 "failed to parse _CRS method, error code %d\n", ret);
+	else if (ret == 0)
+		dev_dbg(&device->dev,
+			"no IO and memory resources present in _CRS\n");
+	else {
+		resource_list_for_each_entry_safe(entry, tmp, list) {
+			if (entry->res->flags & IORESOURCE_DISABLED)
+				resource_list_destroy_entry(entry);
+			else
+				entry->res->name = info->name;
+		}
+		acpi_pci_root_validate_resources(&device->dev, list,
+						 IORESOURCE_MEM);
+		acpi_pci_root_validate_resources(&device->dev, list,
+						 IORESOURCE_IO);
+	}
+
+	return ret;
+}
+
+static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
+{
+	struct resource_entry *entry, *tmp;
+	struct resource *res, *conflict, *root = NULL;
+
+	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+		res = entry->res;
+		if (res->flags & IORESOURCE_MEM)
+			root = &iomem_resource;
+		else if (res->flags & IORESOURCE_IO)
+			root = &ioport_resource;
+		else
+			continue;
+
+		conflict = insert_resource_conflict(root, res);
+		if (conflict) {
+			dev_info(&info->bridge->dev,
+				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
+				 res, conflict->name, conflict);
+			resource_list_destroy_entry(entry);
+		}
+	}
+}
+
+static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
+{
+	struct resource *res;
+	struct resource_entry *entry, *tmp;
+
+	if (!info)
+		return;
+
+	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+		res = entry->res;
+		if (res->parent &&
+		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+			release_resource(res);
+		resource_list_destroy_entry(entry);
+	}
+
+	info->ops->release_info(info);
+}
+
+static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
+{
+	struct resource *res;
+	struct resource_entry *entry;
+
+	resource_list_for_each_entry(entry, &bridge->windows) {
+		res = entry->res;
+		if (res->parent &&
+		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+			release_resource(res);
+	}
+	__acpi_pci_root_release_info(bridge->release_data);
+}
+
+struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
+				     struct acpi_pci_root_ops *ops,
+				     struct acpi_pci_root_info *info,
+				     void *sysdata)
+{
+	int ret, busnum = root->secondary.start;
+	struct acpi_device *device = root->device;
+	int node = acpi_get_node(device->handle);
+	struct pci_bus *bus;
+
+	info->root = root;
+	info->bridge = device;
+	info->ops = ops;
+	INIT_LIST_HEAD(&info->resources);
+	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
+		 root->segment, busnum);
+
+	if (ops->init_info && ops->init_info(info))
+		goto out_release_info;
+	ret = acpi_pci_probe_root_resources(info);
+	if (ops->prepare_resources)
+		ret = ops->prepare_resources(info, ret);
+	if (ret < 0)
+		goto out_release_info;
+	else if (ret > 0)
+		pci_acpi_root_add_resources(info);
+	pci_add_resource(&info->resources, &root->secondary);
+
+	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
+				  sysdata, &info->resources);
+	if (bus) {
+		pci_scan_child_bus(bus);
+		pci_set_host_bridge_release(to_pci_host_bridge(bus->bridge),
+					    acpi_pci_root_release_info, info);
+		if (node != NUMA_NO_NODE)
+			dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n",
+				   node);
+		return bus;
+	}
+
+out_release_info:
+	__acpi_pci_root_release_info(info);
+	return NULL;
+}
+
 void __init acpi_pci_root_init(void)
 {
 	acpi_hest_init();

index a965efa52152..583af37c6030 100644
@@ -52,6 +52,29 @@ static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
 	return ACPI_HANDLE(dev);
 }
 
+struct acpi_pci_root;
+struct acpi_pci_root_ops;
+
+struct acpi_pci_root_info {
+	struct acpi_pci_root		*root;
+	struct acpi_device		*bridge;
+	struct acpi_pci_root_ops	*ops;
+	struct list_head		resources;
+	char				name[16];
+};
+
+struct acpi_pci_root_ops {
+	struct pci_ops *pci_ops;
+	int (*init_info)(struct acpi_pci_root_info *info);
+	void (*release_info)(struct acpi_pci_root_info *info);
+	int (*prepare_resources)(struct acpi_pci_root_info *info, int status);
+};
+
+extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
+					    struct acpi_pci_root_ops *ops,
+					    struct acpi_pci_root_info *info,
+					    void *sd);
+
 void acpi_pci_add_bus(struct pci_bus *bus);
 void acpi_pci_remove_bus(struct pci_bus *bus);
 

index ff9911707160..5bc018559cc4 100644
@@ -401,7 +401,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 	int node;
 
 	if (pci_ignore_seg)
-		domain = 0;
+		root->segment = domain = 0;
 
 	if (domain && !pci_domains_supported) {
 		printk(KERN_WARNING "pci_bus %04x:%02x: "

index 5bc018559cc4..54bcca55b667 100644
@@ -4,16 +4,15 @@
 #include <linux/irq.h>
 #include <linux/dmi.h>
 #include <linux/slab.h>
+#include <linux/pci-acpi.h>
 #include <asm/numa.h>
 #include <asm/pci_x86.h>
 
 struct pci_root_info {
-	struct acpi_device *bridge;
-	char name[16];
+	struct acpi_pci_root_info common;
 	struct pci_sysdata sd;
 #ifdef	CONFIG_PCI_MMCONFIG
 	bool mcfg_added;
-	u16 segment;
 	u8 start_bus;
 	u8 end_bus;
 #endif

@@ -178,15 +177,18 @@ static int check_segment(u16 seg, struct device *dev, char *estr)
 	return 0;
 }
 
-static int setup_mcfg_map(struct pci_root_info *info, u16 seg, u8 start,
-			  u8 end, phys_addr_t addr)
+static int setup_mcfg_map(struct acpi_pci_root_info *ci)
 {
-	int result;
-	struct device *dev = &info->bridge->dev;
+	int result, seg;
+	struct pci_root_info *info;
+	struct acpi_pci_root *root = ci->root;
+	struct device *dev = &ci->bridge->dev;
 
-	info->start_bus = start;
-	info->end_bus = end;
+	info = container_of(ci, struct pci_root_info, common);
+	info->start_bus = (u8)root->secondary.start;
+	info->end_bus = (u8)root->secondary.end;
 	info->mcfg_added = false;
+	seg = info->sd.domain;
 
 	/* return success if MMCFG is not in use */
 	if (raw_pci_ext_ops && raw_pci_ext_ops != &pci_mmcfg)

@@ -195,7 +197,8 @@ static int setup_mcfg_map(struct pci_root_info *info, u16 seg, u8 start,
 	if (!(pci_probe & PCI_PROBE_MMCONF))
 		return check_segment(seg, dev, "MMCONFIG is disabled,");
 
-	result = pci_mmconfig_insert(dev, seg, start, end, addr);
+	result = pci_mmconfig_insert(dev, seg, info->start_bus, info->end_bus,
+				     root->mcfg_addr);
 	if (result == 0) {
 		/* enable MMCFG if it hasn't been enabled yet */
 		if (raw_pci_ext_ops == NULL)

@@ -208,134 +211,55 @@ static int setup_mcfg_map(struct pci_root_info *info, u16 seg, u8 start,
 	return 0;
 }
 
-static void teardown_mcfg_map(struct pci_root_info *info)
+static void teardown_mcfg_map(struct acpi_pci_root_info *ci)
 {
+	struct pci_root_info *info;
+
+	info = container_of(ci, struct pci_root_info, common);
 	if (info->mcfg_added) {
-		pci_mmconfig_delete(info->segment, info->start_bus,
-				    info->end_bus);
+		pci_mmconfig_delete(info->sd.domain,
+				    info->start_bus, info->end_bus);
 		info->mcfg_added = false;
 	}
 }
 #else
-static int setup_mcfg_map(struct pci_root_info *info,
-				    u16 seg, u8 start, u8 end,
-				    phys_addr_t addr)
+static int setup_mcfg_map(struct acpi_pci_root_info *ci)
 {
 	return 0;
 }
-static void teardown_mcfg_map(struct pci_root_info *info)
+
+static void teardown_mcfg_map(struct acpi_pci_root_info *ci)
 {
 }
 #endif
 
-static void validate_resources(struct device *dev, struct list_head *crs_res,
-			       unsigned long type)
+static int pci_acpi_root_get_node(struct acpi_pci_root *root)
 {
-	LIST_HEAD(list);
-	struct resource *res1, *res2, *root = NULL;
-	struct resource_entry *tmp, *entry, *entry2;
-
-	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
-	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
-
-	list_splice_init(crs_res, &list);
-	resource_list_for_each_entry_safe(entry, tmp, &list) {
-		bool free = false;
-		resource_size_t end;
-
-		res1 = entry->res;
-		if (!(res1->flags & type))
-			goto next;
-
-		/* Exclude non-addressable range or non-addressable portion */
-		end = min(res1->end, root->end);
-		if (end <= res1->start) {
-			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
-				 res1);
-			free = true;
-			goto next;
-		} else if (res1->end != end) {
-			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
-				 res1, (unsigned long long)end + 1,
-				 (unsigned long long)res1->end);
-			res1->end = end;
-		}
-
-		resource_list_for_each_entry(entry2, crs_res) {
-			res2 = entry2->res;
-			if (!(res2->flags & type))
-				continue;
-
-			/*
-			 * I don't like throwing away windows because then
-			 * our resources no longer match the ACPI _CRS, but
-			 * the kernel resource tree doesn't allow overlaps.
-			 */
-			if (resource_overlaps(res1, res2)) {
-				res2->start = min(res1->start, res2->start);
-				res2->end = max(res1->end, res2->end);
-				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
-					 res2, res1);
-				free = true;
-				goto next;
-			}
-		}
+	int busnum = root->secondary.start;
+	struct acpi_device *device = root->device;
+	int node = acpi_get_node(device->handle);
 
-next:
-		resource_list_del(entry);
-		if (free)
-			resource_list_free_entry(entry);
-		else
-			resource_list_add_tail(entry, crs_res);
+	if (node == NUMA_NO_NODE) {
+		node = x86_pci_root_bus_node(busnum);
+		if (node != 0 && node != NUMA_NO_NODE)
+			dev_info(&device->dev, FW_BUG "no _PXM; falling back to node %d from hardware (may be inconsistent with ACPI node numbers)\n",
+				node);
 	}
+	if (node != NUMA_NO_NODE && !node_online(node))
+		node = NUMA_NO_NODE;
+
+	return node;
 }
 
-static void add_resources(struct pci_root_info *info,
-			  struct list_head *resources,
-			  struct list_head *crs_res)
+static int pci_acpi_root_init_info(struct acpi_pci_root_info *ci)
 {
-	struct resource_entry *entry, *tmp;
-	struct resource *res, *conflict, *root = NULL;
-
-	validate_resources(&info->bridge->dev, crs_res, IORESOURCE_MEM);
-	validate_resources(&info->bridge->dev, crs_res, IORESOURCE_IO);
-
-	resource_list_for_each_entry_safe(entry, tmp, crs_res) {
-		res = entry->res;
-		if (res->flags & IORESOURCE_MEM)
-			root = &iomem_resource;
-		else if (res->flags & IORESOURCE_IO)
-			root = &ioport_resource;
-		else
-			BUG_ON(res);
-
-		conflict = insert_resource_conflict(root, res);
-		if (conflict) {
-			dev_info(&info->bridge->dev,
-				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
-				 res, conflict->name, conflict);
-			resource_list_destroy_entry(entry);
-		}
-	}
-
-	list_splice_tail(crs_res, resources);
+	return setup_mcfg_map(ci);
 }
 
-static void release_pci_root_info(struct pci_host_bridge *bridge)
+static void pci_acpi_root_release_info(struct acpi_pci_root_info *ci)
 {
-	struct resource *res;
-	struct resource_entry *entry;
-	struct pci_root_info *info = bridge->release_data;
-
-	resource_list_for_each_entry(entry, &bridge->windows) {
-		res = entry->res;
-		if (res->parent &&
-		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
-			release_resource(res);
-	}
-
-	teardown_mcfg_map(info);
-	kfree(info);
+	teardown_mcfg_map(ci);
+	kfree(container_of(ci, struct pci_root_info, common));
 }
 
 /*

@@ -358,47 +282,43 @@ static bool resource_is_pcicfg_ioport(struct resource *res)
 		res->start == 0xCF8 && res->end == 0xCFF;
 }
 
-static void probe_pci_root_info(struct pci_root_info *info,
-				struct acpi_device *device,
-				int busnum, int domain,
-				struct list_head *list)
+static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci,
+					   int status)
 {
-	int ret;
+	struct acpi_device *device = ci->bridge;
+	int busnum = ci->root->secondary.start;
 	struct resource_entry *entry, *tmp;
 
-	sprintf(info->name, "PCI Bus %04x:%02x", domain, busnum);
-	info->bridge = device;
-	ret = acpi_dev_get_resources(device, list,
-				     acpi_dev_filter_resource_type_cb,
-				     (void *)(IORESOURCE_IO | IORESOURCE_MEM));
-	if (ret < 0)
-		dev_warn(&device->dev,
-			 "failed to parse _CRS method, error code %d\n", ret);
-	else if (ret == 0)
-		dev_dbg(&device->dev,
-			"no IO and memory resources present in _CRS\n");
-	else
-		resource_list_for_each_entry_safe(entry, tmp, list) {
-			if ((entry->res->flags & IORESOURCE_DISABLED) ||
-			    resource_is_pcicfg_ioport(entry->res))
+	if (pci_use_crs) {
+		resource_list_for_each_entry_safe(entry, tmp, &ci->resources)
+			if (resource_is_pcicfg_ioport(entry->res))
 				resource_list_destroy_entry(entry);
-			else
-				entry->res->name = info->name;
-		}
+		return status;
+	}
+
+	resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
+		dev_printk(KERN_DEBUG, &device->dev,
+			   "host bridge window %pR (ignored)\n", entry->res);
+		resource_list_destroy_entry(entry);
+	}
+	x86_pci_root_bus_resources(busnum, &ci->resources);
+
+	return 0;
 }
 
+static struct acpi_pci_root_ops acpi_pci_root_ops = {
+	.pci_ops = &pci_root_ops,
+	.init_info = pci_acpi_root_init_info,
+	.release_info = pci_acpi_root_release_info,
+	.prepare_resources = pci_acpi_root_prepare_resources,
+};
+
 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 {
-	struct acpi_device *device = root->device;
-	struct pci_root_info *info;
 	int domain = root->segment;
 	int busnum = root->secondary.start;
-	struct resource_entry *res_entry;
-	LIST_HEAD(crs_res);
-	LIST_HEAD(resources);
+	int node = pci_acpi_root_get_node(root);
 	struct pci_bus *bus;
-	struct pci_sysdata *sd;
-	int node;
 
 	if (pci_ignore_seg)
 		root->segment = domain = 0;

@@ -410,71 +330,33 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 		return NULL;
 	}
 
-	node = acpi_get_node(device->handle);
-	if (node == NUMA_NO_NODE) {
-		node = x86_pci_root_bus_node(busnum);
-		if (node != 0 && node != NUMA_NO_NODE)
-			dev_info(&device->dev, FW_BUG "no _PXM; falling back to node %d from hardware (may be inconsistent with ACPI node numbers)\n",
-				node);
-	}
-
-	if (node != NUMA_NO_NODE && !node_online(node))
-		node = NUMA_NO_NODE;
-
-	info = kzalloc_node(sizeof(*info), GFP_KERNEL, node);
-	if (!info) {
-		printk(KERN_WARNING "pci_bus %04x:%02x: "
-		       "ignored (out of memory)\n", domain, busnum);
-		return NULL;
-	}
-
-	sd = &info->sd;
-	sd->domain = domain;
-	sd->node = node;
-	sd->companion = device;
-
 	bus = pci_find_bus(domain, busnum);
 	if (bus) {
 		/*
 		 * If the desired bus has been scanned already, replace
 		 * its bus->sysdata.
 		 */
-		memcpy(bus->sysdata, sd, sizeof(*sd));
-		kfree(info);
-	} else {
-		/* insert busn res at first */
-		pci_add_resource(&resources,  &root->secondary);
+		struct pci_sysdata sd = {
+			.domain = domain,
+			.node = node,
+			.companion = root->device
+		};
 
-		/*
-		 * _CRS with no apertures is normal, so only fall back to
-		 * defaults or native bridge info if we're ignoring _CRS.
-		 */
-		probe_pci_root_info(info, device, busnum, domain, &crs_res);
-		if (pci_use_crs) {
-			add_resources(info, &resources, &crs_res);
-		} else {
-			resource_list_for_each_entry(res_entry, &crs_res)
-				dev_printk(KERN_DEBUG, &device->dev,
-					   "host bridge window %pR (ignored)\n",
-					   res_entry->res);
-			resource_list_free(&crs_res);
-			x86_pci_root_bus_resources(busnum, &resources);
-		}
-
-		if (!setup_mcfg_map(info, domain, (u8)root->secondary.start,
-				    (u8)root->secondary.end, root->mcfg_addr))
-			bus = pci_create_root_bus(NULL, busnum, &pci_root_ops,
-						  sd, &resources);
-
-		if (bus) {
-			pci_scan_child_bus(bus);
-			pci_set_host_bridge_release(
-				to_pci_host_bridge(bus->bridge),
-				release_pci_root_info, info);
-		} else {
-			resource_list_free(&resources);
-			teardown_mcfg_map(info);
-			kfree(info);
+		memcpy(bus->sysdata, &sd, sizeof(sd));
+	} else {
+		struct pci_root_info *info;
+
+		info = kzalloc_node(sizeof(*info), GFP_KERNEL, node);
+		if (!info)
+			dev_err(&root->device->dev,
+				"pci_bus %04x:%02x: ignored (out of memory)\n",
+				domain, busnum);
+		else {
+			info->sd.domain = domain;
+			info->sd.node = node;
+			info->sd.companion = root->device;
+			bus = acpi_pci_root_create(root, &acpi_pci_root_ops,
+						   &info->common, &info->sd);
 		}
 	}
 

@@ -487,9 +369,6 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 			pcie_bus_configure_settings(child);
 	}
 
-	if (bus && node != NUMA_NO_NODE)
-		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
-
 	return bus;
 }
 

index 5dd3753a2739..21d4c2d5bc79 100644
@@ -116,15 +116,12 @@ struct pci_ops pci_root_ops = {
 };
 
 struct pci_root_info {
+	struct acpi_pci_root_info common;
 	struct pci_controller controller;
-	struct acpi_device *bridge;
-	struct list_head resources;
 	struct list_head io_resources;
-	char name[16];
 };
 
-static unsigned int
-new_space (u64 phys_base, int sparse)
+static unsigned int new_space(u64 phys_base, int sparse)
 {
 	u64 mmio_base;
 	int i;

@@ -160,11 +157,11 @@ static int add_io_space(struct device *dev, struct pci_root_info *info,
 	unsigned long base, min, max, base_port;
 	unsigned int sparse = 0, space_nr, len;
 
-	len = strlen(info->name) + 32;
+	len = strlen(info->common.name) + 32;
 	iospace = resource_list_create_entry(NULL, len);
 	if (!iospace) {
 		dev_err(dev, "PCI: No memory for %s I/O port space\n",
-			info->name);
+			info->common.name);
 		return -ENOMEM;
 	}
 

@@ -179,7 +176,7 @@ static int add_io_space(struct device *dev, struct pci_root_info *info,
 	max = res->end - entry->offset;
 	base = __pa(io_space[space_nr].mmio_base);
 	base_port = IO_SPACE_BASE(space_nr);
-	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->name,
+	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->common.name,
 		 base_port + min, base_port + max);
 
 	/*

@@ -234,217 +231,80 @@ static bool resource_is_pcicfg_ioport(struct resource *res)
 		res->start == 0xCF8 && res->end == 0xCFF;
 }
 
-static int
-probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
-		    int busnum, int domain)
+static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci,
+					   int status)
 {
-	int ret;
-	struct list_head *list = &info->resources;
+	struct device *dev = &ci->bridge->dev;
+	struct pci_root_info *info;
+	struct resource *res;
 	struct resource_entry *entry, *tmp;
 
-	ret = acpi_dev_get_resources(device, list,
-				     acpi_dev_filter_resource_type_cb,
-				     (void *)(IORESOURCE_IO | IORESOURCE_MEM));
-	if (ret < 0)
-		dev_warn(&device->dev,
-			 "failed to parse _CRS method, error code %d\n", ret);
-	else if (ret == 0)
-		dev_dbg(&device->dev,
-			"no IO and memory resources present in _CRS\n");
-	else
-		resource_list_for_each_entry_safe(entry, tmp, list) {
-			if ((entry->res->flags & IORESOURCE_DISABLED) ||
-			    resource_is_pcicfg_ioport(entry->res))
-				resource_list_destroy_entry(entry);
-			else
-				entry->res->name = info->name;
-		}
-
-	return ret;
-}
-
-static void validate_resources(struct device *dev, struct list_head *resources,
-			       unsigned long type)
-{
-	LIST_HEAD(list);
-	struct resource *res1, *res2, *root = NULL;
-	struct resource_entry *tmp, *entry, *entry2;
-
-	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
-	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
-
-	list_splice_init(resources, &list);
-	resource_list_for_each_entry_safe(entry, tmp, &list) {
-		bool free = false;
-		resource_size_t end;
-
-		res1 = entry->res;
-		if (!(res1->flags & type))
-			goto next;
-
-		/* Exclude non-addressable range or non-addressable portion */
-		end = min(res1->end, root->end);
-		if (end <= res1->start) {
-			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
-				 res1);
-			free = true;
-			goto next;
-		} else if (res1->end != end) {
-			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
-				 res1, (unsigned long long)end + 1,
-				 (unsigned long long)res1->end);
-			res1->end = end;
-		}
-
-		resource_list_for_each_entry(entry2, resources) {
-			res2 = entry2->res;
-			if (!(res2->flags & type))
-				continue;
-
-			/*
-			 * I don't like throwing away windows because then
-			 * our resources no longer match the ACPI _CRS, but
-			 * the kernel resource tree doesn't allow overlaps.
-			 */
-			if (resource_overlaps(res1, res2)) {
-				res2->start = min(res1->start, res2->start);
-				res2->end = max(res1->end, res2->end);
-				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
-					 res2, res1);
-				free = true;
-				goto next;
+	if (status > 0) {
+		info = container_of(ci, struct pci_root_info, common);
+		resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
+			res = entry->res;
+			if (res->flags & IORESOURCE_MEM) {
+				/*
+				 * HP's firmware has a hack to work around a
+				 * Windows bug. Ignore these tiny memory ranges.
+				 */
+				if (resource_size(res) <= 16) {
+					resource_list_del(entry);
+					insert_resource(&iomem_resource,
+							entry->res);
+					resource_list_add_tail(entry,
+							&info->io_resources);
+				}
+			} else if (res->flags & IORESOURCE_IO) {
+				if (resource_is_pcicfg_ioport(entry->res))
+					resource_list_destroy_entry(entry);
+				else if (add_io_space(dev, info, entry))
+					resource_list_destroy_entry(entry);
 			}
 		}
-
-next:
-		resource_list_del(entry);
-		if (free)
-			resource_list_free_entry(entry);
-		else
-			resource_list_add_tail(entry, resources);
 	}
-}
 
-static void add_resources(struct pci_root_info *info, struct device *dev)
-{
-	struct resource_entry *entry, *tmp;
-	struct resource *res, *conflict, *root = NULL;
-	struct list_head *list = &info->resources;
-
-	validate_resources(dev, list, IORESOURCE_MEM);
-	validate_resources(dev, list, IORESOURCE_IO);
-
-	resource_list_for_each_entry_safe(entry, tmp, list) {
-		res = entry->res;
-		if (res->flags & IORESOURCE_MEM) {
-			root = &iomem_resource;
-			/*
-			 * HP's firmware has a hack to work around a Windows
-			 * bug. Ignore these tiny memory ranges.
-			 */
-			if (resource_size(res) <= 16) {
-				resource_list_destroy_entry(entry);
-				continue;
-			}
-		} else if (res->flags & IORESOURCE_IO) {
-			root = &ioport_resource;
-			if (add_io_space(&info->bridge->dev, info, entry)) {
-				resource_list_destroy_entry(entry);
-				continue;
-			}
-		} else {
-			BUG_ON(res);
-		}
-
-		conflict = insert_resource_conflict(root, res);
-		if (conflict) {
-			dev_info(dev,
-				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
-				 res, conflict->name, conflict);
-			resource_list_destroy_entry(entry);
-		}
-	}
+	return status;
 }
 
-static void __release_pci_root_info(struct pci_root_info *info)
+static void pci_acpi_root_release_info(struct acpi_pci_root_info *ci)
 {
-	struct resource *res;
-	struct resource_entry *entry, *tentry;
+	struct pci_root_info *info;
+	struct resource_entry *entry, *tmp;
 
-	resource_list_for_each_entry_safe(entry, tentry, &info->io_resources) {
+	info = container_of(ci, struct pci_root_info, common);
+	resource_list_for_each_entry_safe(entry, tmp, &info->io_resources) {
 		release_resource(entry->res);
 		resource_list_destroy_entry(entry);
 	}
-
-	resource_list_for_each_entry_safe(entry, tentry, &info->resources) {
-		res = entry->res;
-		if (res->parent &&
-		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
-			release_resource(res);
-		resource_list_destroy_entry(entry);
-	}
-
 	kfree(info);
 }
 
-static void release_pci_root_info(struct pci_host_bridge *bridge)
-{
-	struct pci_root_info *info = bridge->release_data;
-
-	__release_pci_root_info(info);
-}
+static struct acpi_pci_root_ops pci_acpi_root_ops = {
+	.pci_ops = &pci_root_ops,
+	.release_info = pci_acpi_root_release_info,
+	.prepare_resources = pci_acpi_root_prepare_resources,
+};
 
 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 {
 	struct acpi_device *device = root->device;
-	int domain = root->segment;
-	int bus = root->secondary.start;
 	struct pci_root_info *info;
-	struct pci_bus *pbus;
-	int ret;
 
 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (!info) {
 		dev_err(&device->dev,
 			"pci_bus %04x:%02x: ignored (out of memory)\n",
-			domain, bus);
+			root->segment, (int)root->secondary.start);
 		return NULL;
 	}
 
-	info->controller.segment = domain;
+	info->controller.segment = root->segment;
 	info->controller.companion = device;
 	info->controller.node = acpi_get_node(device->handle);
-	info->bridge = device;
-	INIT_LIST_HEAD(&info->resources);
 	INIT_LIST_HEAD(&info->io_resources);
-	snprintf(info->name, sizeof(info->name),
-		 "PCI Bus %04x:%02x", domain, bus);
-
-	ret = probe_pci_root_info(info, device, bus, domain);
-	if (ret <= 0) {
-		kfree(info);
-		return NULL;
-	}
-	add_resources(info, &info->bridge->dev);
-	pci_add_resource(&info->resources, &root->secondary);
-
-	/*
-	 * See arch/x86/pci/acpi.c.
-	 * The desired pci bus might already be scanned in a quirk. We
-	 * should handle the case here, but it appears that IA64 hasn't
-	 * such quirk. So we just ignore the case now.
-	 */
-	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops,
-				   &info->controller, &info->resources);
-	if (!pbus) {
-		__release_pci_root_info(info);
-		return NULL;
-	}
-
-	pci_set_host_bridge_release(to_pci_host_bridge(pbus->bridge),
-			release_pci_root_info, info);
-	pci_scan_child_bus(pbus);
-	return pbus;
+	return acpi_pci_root_create(root, &pci_acpi_root_ops,
+				    &info->common, &info->controller);
 }
 
 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)