1 files changed, 459 insertions, 201 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 86b69f85f900..8fa2d4be88de 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -25,10 +25,13 @@
 #include <linux/ioport.h>
 #include <linux/cache.h>
 #include <linux/slab.h>
+#include <asm-generic/pci-bridge.h>
 #include "pci.h"
 
-struct resource_list_x {
-	struct resource_list_x *next;
+unsigned int pci_flags;
+
+struct pci_dev_resource {
+	struct list_head list;
 	struct resource *res;
 	struct pci_dev *dev;
 	resource_size_t start;
@@ -38,21 +41,14 @@ struct resource_list_x {
 	unsigned long flags;
 };
 
-#define free_list(type, head) do {                      \
-	struct type *list, *tmp;			\
-	for (list = (head)->next; list;) {		\
-		tmp = list;				\
-		list = list->next;			\
-		kfree(tmp);				\
-	}						\
-	(head)->next = NULL;				\
-} while (0)
-
-int pci_realloc_enable = 0;
-#define pci_realloc_enabled() pci_realloc_enable
-void pci_realloc(void)
+static void free_list(struct list_head *head)
 {
-	pci_realloc_enable = 1;
+	struct pci_dev_resource *dev_res, *tmp;
+
+	list_for_each_entry_safe(dev_res, tmp, head, list) {
+		list_del(&dev_res->list);
+		kfree(dev_res);
+	}
 }
 
 /**
@@ -64,21 +60,18 @@ void pci_realloc(void)
  * @add_size:	additional size to be optionally added
  *              to the resource
  */
-static void add_to_list(struct resource_list_x *head,
+static int add_to_list(struct list_head *head,
 		 struct pci_dev *dev, struct resource *res,
 		 resource_size_t add_size, resource_size_t min_align)
 {
-	struct resource_list_x *list = head;
-	struct resource_list_x *ln = list->next;
-	struct resource_list_x *tmp;
+	struct pci_dev_resource *tmp;
 
-	tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+	tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
 	if (!tmp) {
 		pr_warning("add_to_list: kmalloc() failed!\n");
-		return;
+		return -ENOMEM;
 	}
 
-	tmp->next = ln;
 	tmp->res = res;
 	tmp->dev = dev;
 	tmp->start = res->start;
@@ -86,19 +79,100 @@ static void add_to_list(struct resource_list_x *head,
 	tmp->flags = res->flags;
 	tmp->add_size = add_size;
 	tmp->min_align = min_align;
-	list->next = tmp;
+
+	list_add(&tmp->list, head);
+
+	return 0;
 }
 
-static void add_to_failed_list(struct resource_list_x *head,
-				struct pci_dev *dev, struct resource *res)
+static void remove_from_list(struct list_head *head,
+				 struct resource *res)
 {
-	add_to_list(head, dev, res,
-			0 /* dont care */,
-			0 /* dont care */);
+	struct pci_dev_resource *dev_res, *tmp;
+
+	list_for_each_entry_safe(dev_res, tmp, head, list) {
+		if (dev_res->res == res) {
+			list_del(&dev_res->list);
+			kfree(dev_res);
+			break;
+		}
+	}
+}
+
+static resource_size_t get_res_add_size(struct list_head *head,
+					struct resource *res)
+{
+	struct pci_dev_resource *dev_res;
+
+	list_for_each_entry(dev_res, head, list) {
+		if (dev_res->res == res) {
+			int idx = res - &dev_res->dev->resource[0];
+
+			dev_printk(KERN_DEBUG, &dev_res->dev->dev,
+				 "res[%d]=%pR get_res_add_size add_size %llx\n",
+				 idx, dev_res->res,
+				 (unsigned long long)dev_res->add_size);
+
+			return dev_res->add_size;
+		}
+	}
+
+	return 0;
+}
+
+/* Sort resources by alignment */
+static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
+{
+	int i;
+
+	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+		struct resource *r;
+		struct pci_dev_resource *dev_res, *tmp;
+		resource_size_t r_align;
+		struct list_head *n;
+
+		r = &dev->resource[i];
+
+		if (r->flags & IORESOURCE_PCI_FIXED)
+			continue;
+
+		if (!(r->flags) || r->parent)
+			continue;
+
+		r_align = pci_resource_alignment(dev, r);
+		if (!r_align) {
+			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
+				 i, r);
+			continue;
+		}
+
+		tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
+		if (!tmp)
+			panic("pdev_sort_resources(): "
+			      "kmalloc() failed!\n");
+		tmp->res = r;
+		tmp->dev = dev;
+
+		/* fallback is smallest one or list is empty*/
+		n = head;
+		list_for_each_entry(dev_res, head, list) {
+			resource_size_t align;
+
+			align = pci_resource_alignment(dev_res->dev,
+							 dev_res->res);
+
+			if (r_align > align) {
+				n = &dev_res->list;
+				break;
+			}
+		}
+		/* Insert it just before n*/
+		list_add_tail(&tmp->list, n);
+	}
 }
 
 static void __dev_sort_resources(struct pci_dev *dev,
-				 struct resource_list *head)
+				 struct list_head *head)
 {
 	u16 class = dev->class >> 8;
 
@@ -136,49 +210,54 @@ static inline void reset_resource(struct resource *res)
  * additional resources for the element, provided the element
  * is in the head list.
  */
-static void reassign_resources_sorted(struct resource_list_x *realloc_head,
-		struct resource_list *head)
+static void reassign_resources_sorted(struct list_head *realloc_head,
+		struct list_head *head)
 {
 	struct resource *res;
-	struct resource_list_x *list, *tmp, *prev;
-	struct resource_list *hlist;
+	struct pci_dev_resource *add_res, *tmp;
+	struct pci_dev_resource *dev_res;
 	resource_size_t add_size;
 	int idx;
 
-	prev = realloc_head;
-	for (list = realloc_head->next; list;) {
-		res = list->res;
+	list_for_each_entry_safe(add_res, tmp, realloc_head, list) {
+		bool found_match = false;
+
+		res = add_res->res;
 		/* skip resource that has been reset */
 		if (!res->flags)
 			goto out;
 
 		/* skip this resource if not found in head list */
-		for (hlist = head->next; hlist && hlist->res != res;
-				hlist = hlist->next);
-		if (!hlist) { /* just skip */
-			prev = list;
-			list = list->next;
-			continue;
+		list_for_each_entry(dev_res, head, list) {
+			if (dev_res->res == res) {
+				found_match = true;
+				break;
+			}
 		}
+		if (!found_match)/* just skip */
+			continue;
 
-		idx = res - &list->dev->resource[0];
-		add_size=list->add_size;
+		idx = res - &add_res->dev->resource[0];
+		add_size = add_res->add_size;
 		if (!resource_size(res)) {
-			res->start = list->start;
+			res->start = add_res->start;
 			res->end = res->start + add_size - 1;
-			if(pci_assign_resource(list->dev, idx))
+			if (pci_assign_resource(add_res->dev, idx))
 				reset_resource(res);
 		} else {
-			resource_size_t align = list->min_align;
-			res->flags |= list->flags & (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN);
-			if (pci_reassign_resource(list->dev, idx, add_size, align))
-				dev_printk(KERN_DEBUG, &list->dev->dev, "failed to add optional resources res=%pR\n",
-							res);
+			resource_size_t align = add_res->min_align;
+			res->flags |= add_res->flags &
+				 (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN);
+			if (pci_reassign_resource(add_res->dev, idx,
+						  add_size, align))
+				dev_printk(KERN_DEBUG, &add_res->dev->dev,
+					   "failed to add %llx res[%d]=%pR\n",
+					   (unsigned long long)add_size,
+					   idx, res);
 		}
 out:
-		tmp = list;
-		prev->next = list = list->next;
-		kfree(tmp);
+		list_del(&add_res->list);
+		kfree(add_res);
 	}
 }
 
@@ -192,35 +271,99 @@ out:
  * Satisfy resource requests of each element in the list. Add
  * requests that could not satisfied to the failed_list.
  */
-static void assign_requested_resources_sorted(struct resource_list *head,
-				 struct resource_list_x *fail_head)
+static void assign_requested_resources_sorted(struct list_head *head,
+				 struct list_head *fail_head)
 {
 	struct resource *res;
-	struct resource_list *list;
+	struct pci_dev_resource *dev_res;
 	int idx;
 
-	for (list = head->next; list; list = list->next) {
-		res = list->res;
-		idx = res - &list->dev->resource[0];
-		if (resource_size(res) && pci_assign_resource(list->dev, idx)) {
-			if (fail_head && !pci_is_root_bus(list->dev->bus)) {
+	list_for_each_entry(dev_res, head, list) {
+		res = dev_res->res;
+		idx = res - &dev_res->dev->resource[0];
+		if (resource_size(res) &&
+		    pci_assign_resource(dev_res->dev, idx)) {
+			if (fail_head && !pci_is_root_bus(dev_res->dev->bus)) {
 				/*
 				 * if the failed res is for ROM BAR, and it will
 				 * be enabled later, don't add it to the list
 				 */
 				if (!((idx == PCI_ROM_RESOURCE) &&
 				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
-					add_to_failed_list(fail_head, list->dev, res);
+					add_to_list(fail_head,
+						    dev_res->dev, res,
+						    0 /* dont care */,
+						    0 /* dont care */);
 			}
 			reset_resource(res);
 		}
 	}
 }
 
-static void __assign_resources_sorted(struct resource_list *head,
-				 struct resource_list_x *realloc_head,
-				 struct resource_list_x *fail_head)
+static void __assign_resources_sorted(struct list_head *head,
+				 struct list_head *realloc_head,
+				 struct list_head *fail_head)
 {
+	/*
+	 * Should not assign requested resources at first.
+	 *   they could be adjacent, so later reassign can not reallocate
+	 *   them one by one in parent resource window.
+	 * Try to assign requested + add_size at begining
+	 *  if could do that, could get out early.
+	 *  if could not do that, we still try to assign requested at first,
+	 *    then try to reassign add_size for some resources.
+	 */
+	LIST_HEAD(save_head);
+	LIST_HEAD(local_fail_head);
+	struct pci_dev_resource *save_res;
+	struct pci_dev_resource *dev_res;
+
+	/* Check if optional add_size is there */
+	if (!realloc_head || list_empty(realloc_head))
+		goto requested_and_reassign;
+
+	/* Save original start, end, flags etc at first */
+	list_for_each_entry(dev_res, head, list) {
+		if (add_to_list(&save_head, dev_res->dev, dev_res->res, 0, 0)) {
+			free_list(&save_head);
+			goto requested_and_reassign;
+		}
+	}
+
+	/* Update res in head list with add_size in realloc_head list */
+	list_for_each_entry(dev_res, head, list)
+		dev_res->res->end += get_res_add_size(realloc_head,
+							dev_res->res);
+
+	/* Try updated head list with add_size added */
+	assign_requested_resources_sorted(head, &local_fail_head);
+
+	/* all assigned with add_size ? */
+	if (list_empty(&local_fail_head)) {
+		/* Remove head list from realloc_head list */
+		list_for_each_entry(dev_res, head, list)
+			remove_from_list(realloc_head, dev_res->res);
+		free_list(&save_head);
+		free_list(head);
+		return;
+	}
+
+	free_list(&local_fail_head);
+	/* Release assigned resource */
+	list_for_each_entry(dev_res, head, list)
+		if (dev_res->res->parent)
+			release_resource(dev_res->res);
+	/* Restore start/end/flags from saved list */
+	list_for_each_entry(save_res, &save_head, list) {
+		struct resource *res = save_res->res;
+
+		res->start = save_res->start;
+		res->end = save_res->end;
+		res->flags = save_res->flags;
+	}
+	free_list(&save_head);
+
+requested_and_reassign:
 	/* Satisfy the must-have resource requests */
 	assign_requested_resources_sorted(head, fail_head);
 
@@ -228,28 +371,27 @@ static void __assign_resources_sorted(struct resource_list *head,
 		requests */
 	if (realloc_head)
 		reassign_resources_sorted(realloc_head, head);
-	free_list(resource_list, head);
+	free_list(head);
 }
 
 static void pdev_assign_resources_sorted(struct pci_dev *dev,
-				 struct resource_list_x *fail_head)
+				 struct list_head *add_head,
+				 struct list_head *fail_head)
 {
-	struct resource_list head;
+	LIST_HEAD(head);
 
-	head.next = NULL;
 	__dev_sort_resources(dev, &head);
-	__assign_resources_sorted(&head, NULL, fail_head);
+	__assign_resources_sorted(&head, add_head, fail_head);
 
 }
 
 static void pbus_assign_resources_sorted(const struct pci_bus *bus,
-					 struct resource_list_x *realloc_head,
-					 struct resource_list_x *fail_head)
+					 struct list_head *realloc_head,
+					 struct list_head *fail_head)
 {
 	struct pci_dev *dev;
-	struct resource_list head;
+	LIST_HEAD(head);
 
-	head.next = NULL;
 	list_for_each_entry(dev, &bus->devices, bus_list)
 		__dev_sort_resources(dev, &head);
 
@@ -548,20 +690,6 @@ static resource_size_t calculate_memsize(resource_size_t size,
 	return size;
 }
 
-static resource_size_t get_res_add_size(struct resource_list_x *realloc_head,
-					struct resource *res)
-{
-	struct resource_list_x *list;
-
-	/* check if it is in realloc_head list */
-	for (list = realloc_head->next; list && list->res != res;
-			list = list->next);
-	if (list)
-		return list->add_size;
-
-	return 0;
-}
-
 /**
  * pbus_size_io() - size the io window of a given bus
  *
@@ -576,7 +704,7 @@ static resource_size_t get_res_add_size(struct resource_list_x *realloc_head,
  * We must be careful with the ISA aliasing though.
  */
 static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
-		resource_size_t add_size, struct resource_list_x *realloc_head)
+		resource_size_t add_size, struct list_head *realloc_head)
 {
 	struct pci_dev *dev;
 	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
@@ -612,7 +740,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 	if (children_add_size > add_size)
 		add_size = children_add_size;
 	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
-		calculate_iosize(size, min_size+add_size, size1,
+		calculate_iosize(size, min_size, add_size + size1,
 			resource_size(b_res), 4096);
 	if (!size0 && !size1) {
 		if (b_res->start || b_res->end)
@@ -626,8 +754,12 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 	b_res->start = 4096;
 	b_res->end = b_res->start + size0 - 1;
 	b_res->flags |= IORESOURCE_STARTALIGN;
-	if (size1 > size0 && realloc_head)
+	if (size1 > size0 && realloc_head) {
 		add_to_list(realloc_head, bus->self, b_res, size1-size0, 4096);
+		dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window "
+				 "%pR to [bus %02x-%02x] add_size %lx\n", b_res,
+				 bus->secondary, bus->subordinate, size1-size0);
+	}
 }
 
 /**
@@ -644,7 +776,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 			 unsigned long type, resource_size_t min_size,
 			resource_size_t add_size,
-			struct resource_list_x *realloc_head)
+			struct list_head *realloc_head)
 {
 	struct pci_dev *dev;
 	resource_size_t min_align, align, size, size0, size1;
@@ -726,7 +858,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 	if (children_add_size > add_size)
 		add_size = children_add_size;
 	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
-		calculate_memsize(size, min_size+add_size, 0,
+		calculate_memsize(size, min_size, add_size,
 				resource_size(b_res), min_align);
 	if (!size0 && !size1) {
 		if (b_res->start || b_res->end)
@@ -739,8 +871,12 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 	b_res->start = min_align;
 	b_res->end = size0 + min_align - 1;
 	b_res->flags |= IORESOURCE_STARTALIGN | mem64_mask;
-	if (size1 > size0 && realloc_head)
+	if (size1 > size0 && realloc_head) {
 		add_to_list(realloc_head, bus->self, b_res, size1-size0, min_align);
+		dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window "
+				 "%pR to [bus %02x-%02x] add_size %llx\n", b_res,
+				 bus->secondary, bus->subordinate, (unsigned long long)size1-size0);
+	}
 	return 1;
 }
 
@@ -754,25 +890,48 @@ unsigned long pci_cardbus_resource_alignment(struct resource *res)
 }
 
 static void pci_bus_size_cardbus(struct pci_bus *bus,
-			struct resource_list_x *realloc_head)
+			struct list_head *realloc_head)
 {
 	struct pci_dev *bridge = bus->self;
 	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
+	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
 	u16 ctrl;
 
+	if (b_res[0].parent)
+		goto handle_b_res_1;
 	/*
 	 * Reserve some resources for CardBus.  We reserve
 	 * a fixed amount of bus space for CardBus bridges.
 	 */
-	b_res[0].start = 0;
-	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
-	if (realloc_head)
-		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size, 0 /* dont care */);
+	b_res[0].start = pci_cardbus_io_size;
+	b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
+	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[0].end -= pci_cardbus_io_size;
+		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
+				pci_cardbus_io_size);
+	}
 
-	b_res[1].start = 0;
-	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
-	if (realloc_head)
-		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size, 0 /* dont care */);
+handle_b_res_1:
+	if (b_res[1].parent)
+		goto handle_b_res_2;
+	b_res[1].start = pci_cardbus_io_size;
+	b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1;
+	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[1].end -= pci_cardbus_io_size;
+		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size,
+				 pci_cardbus_io_size);
+	}
+
+handle_b_res_2:
+	/* MEM1 must not be pref mmio */
+	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
+		ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
+		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
+		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+	}
 
 	/*
 	 * Check whether prefetchable memory is supported
@@ -785,38 +944,46 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
 	}
 
+	if (b_res[2].parent)
+		goto handle_b_res_3;
 	/*
 	 * If we have prefetchable memory support, allocate
 	 * two regions.  Otherwise, allocate one region of
 	 * twice the size.
 	 */
 	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
-		b_res[2].start = 0;
-		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+2, pci_cardbus_mem_size, 0 /* dont care */);
-
-		b_res[3].start = 0;
-		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+3, pci_cardbus_mem_size, 0 /* dont care */);
-	} else {
-		b_res[3].start = 0;
-		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+3, pci_cardbus_mem_size * 2, 0 /* dont care */);
+		b_res[2].start = pci_cardbus_mem_size;
+		b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1;
+		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH |
+				  IORESOURCE_STARTALIGN;
+		if (realloc_head) {
+			b_res[2].end -= pci_cardbus_mem_size;
+			add_to_list(realloc_head, bridge, b_res+2,
+				 pci_cardbus_mem_size, pci_cardbus_mem_size);
+		}
+
+		/* reduce that to half */
+		b_res_3_size = pci_cardbus_mem_size;
+	}
+
+handle_b_res_3:
+	if (b_res[3].parent)
+		goto handle_done;
+	b_res[3].start = pci_cardbus_mem_size;
+	b_res[3].end = b_res[3].start + b_res_3_size - 1;
+	b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[3].end -= b_res_3_size;
+		add_to_list(realloc_head, bridge, b_res+3, b_res_3_size,
+				 pci_cardbus_mem_size);
 	}
 
-	/* set the size of the resource to zero, so that the resource does not
-	 * get assigned during required-resource allocation cycle but gets assigned
-	 * during the optional-resource allocation cycle.
- 	 */
-	b_res[0].start = b_res[1].start = b_res[2].start = b_res[3].start = 1;
-	b_res[0].end = b_res[1].end = b_res[2].end = b_res[3].end = 0;
+handle_done:
+	;
 }
 
 void __ref __pci_bus_size_bridges(struct pci_bus *bus,
-			struct resource_list_x *realloc_head)
+			struct list_head *realloc_head)
 {
 	struct pci_dev *dev;
 	unsigned long mask, prefmask;
@@ -858,7 +1025,8 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
 		 * Follow thru
 		 */
 	default:
-		pbus_size_io(bus, 0, additional_io_size, realloc_head);
+		pbus_size_io(bus, realloc_head ? 0 : additional_io_size,
+			     additional_io_size, realloc_head);
 		/* If the bridge supports prefetchable range, size it
 		   separately. If it doesn't, or its prefetchable window
 		   has already been allocated by arch code, try
@@ -866,11 +1034,15 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
 		   resources. */
 		mask = IORESOURCE_MEM;
 		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
-		if (pbus_size_mem(bus, prefmask, prefmask, 0, additional_mem_size, realloc_head))
+		if (pbus_size_mem(bus, prefmask, prefmask,
+				  realloc_head ? 0 : additional_mem_size,
+				  additional_mem_size, realloc_head))
 			mask = prefmask; /* Success, size non-prefetch only. */
 		else
 			additional_mem_size += additional_mem_size;
-		pbus_size_mem(bus, mask, IORESOURCE_MEM, 0, additional_mem_size, realloc_head);
+		pbus_size_mem(bus, mask, IORESOURCE_MEM,
+				realloc_head ? 0 : additional_mem_size,
+				additional_mem_size, realloc_head);
 		break;
 	}
 }
@@ -882,8 +1054,8 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus)
 EXPORT_SYMBOL(pci_bus_size_bridges);
 
 static void __ref __pci_bus_assign_resources(const struct pci_bus *bus,
-					 struct resource_list_x *realloc_head,
-					 struct resource_list_x *fail_head)
+					 struct list_head *realloc_head,
+					 struct list_head *fail_head)
 {
 	struct pci_bus *b;
 	struct pci_dev *dev;
@@ -922,17 +1094,19 @@ void __ref pci_bus_assign_resources(const struct pci_bus *bus)
 EXPORT_SYMBOL(pci_bus_assign_resources);
 
 static void __ref __pci_bridge_assign_resources(const struct pci_dev *bridge,
-					 struct resource_list_x *fail_head)
+					 struct list_head *add_head,
+					 struct list_head *fail_head)
 {
 	struct pci_bus *b;
 
-	pdev_assign_resources_sorted((struct pci_dev *)bridge, fail_head);
+	pdev_assign_resources_sorted((struct pci_dev *)bridge,
+					 add_head, fail_head);
 
 	b = bridge->subordinate;
 	if (!b)
 		return;
 
-	__pci_bus_assign_resources(b, NULL, fail_head);
+	__pci_bus_assign_resources(b, add_head, fail_head);
 
 	switch (bridge->class >> 8) {
 	case PCI_CLASS_BRIDGE_PCI:
@@ -1095,6 +1269,58 @@ static int __init pci_get_max_depth(void)
 	return depth;
 }
 
+/*
+ * -1: undefined, will auto detect later
+ *  0: disabled by user
+ *  1: disabled by auto detect
+ *  2: enabled by user
+ *  3: enabled by auto detect
+ */
+enum enable_type {
+	undefined = -1,
+	user_disabled,
+	auto_disabled,
+	user_enabled,
+	auto_enabled,
+};
+
+static enum enable_type pci_realloc_enable __initdata = undefined;
+void __init pci_realloc_get_opt(char *str)
+{
+	if (!strncmp(str, "off", 3))
+		pci_realloc_enable = user_disabled;
+	else if (!strncmp(str, "on", 2))
+		pci_realloc_enable = user_enabled;
+}
+static bool __init pci_realloc_enabled(void)
+{
+	return pci_realloc_enable >= user_enabled;
+}
+
+static void __init pci_realloc_detect(void)
+{
+#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
+	struct pci_dev *dev = NULL;
+
+	if (pci_realloc_enable != undefined)
+		return;
+
+	for_each_pci_dev(dev) {
+		int i;
+
+		for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) {
+			struct resource *r = &dev->resource[i];
+
+			/* Not assigned, or rejected by kernel ? */
+			if (r->flags && !r->start) {
+				pci_realloc_enable = auto_enabled;
+
+				return;
+			}
+		}
+	}
+#endif
+}
 
 /*
  * first try will not touch pci bridge res
@@ -1105,59 +1331,57 @@ void __init
 pci_assign_unassigned_resources(void)
 {
 	struct pci_bus *bus;
-	struct resource_list_x realloc_list; /* list of resources that
+	LIST_HEAD(realloc_head); /* list of resources that
 					want additional resources */
+	struct list_head *add_list = NULL;
 	int tried_times = 0;
 	enum release_type rel_type = leaf_only;
-	struct resource_list_x head, *list;
+	LIST_HEAD(fail_head);
+	struct pci_dev_resource *fail_res;
 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
 				  IORESOURCE_PREFETCH;
-	unsigned long failed_type;
-	int max_depth = pci_get_max_depth();
-	int pci_try_num;
-
+	int pci_try_num = 1;
 
-	head.next = NULL;
-	realloc_list.next = NULL;
+	/* don't realloc if asked to do so */
+	pci_realloc_detect();
+	if (pci_realloc_enabled()) {
+		int max_depth = pci_get_max_depth();
 
-	pci_try_num = max_depth + 1;
-	printk(KERN_DEBUG "PCI: max bus depth: %d pci_try_num: %d\n",
-		 max_depth, pci_try_num);
+		pci_try_num = max_depth + 1;
+		printk(KERN_DEBUG "PCI: max bus depth: %d pci_try_num: %d\n",
+			 max_depth, pci_try_num);
+	}
 
 again:
+	/*
+	 * last try will use add_list, otherwise will try good to have as
+	 * must have, so can realloc parent bridge resource
+	 */
+	if (tried_times + 1 == pci_try_num)
+		add_list = &realloc_head;
 	/* Depth first, calculate sizes and alignments of all
 	   subordinate buses. */
 	list_for_each_entry(bus, &pci_root_buses, node)
-		__pci_bus_size_bridges(bus, &realloc_list);
+		__pci_bus_size_bridges(bus, add_list);
 
 	/* Depth last, allocate resources and update the hardware. */
 	list_for_each_entry(bus, &pci_root_buses, node)
-		__pci_bus_assign_resources(bus, &realloc_list, &head);
-	BUG_ON(realloc_list.next);
+		__pci_bus_assign_resources(bus, add_list, &fail_head);
+	if (add_list)
+		BUG_ON(!list_empty(add_list));
 	tried_times++;
 
 	/* any device complain? */
-	if (!head.next)
+	if (list_empty(&fail_head))
 		goto enable_and_dump;
 
-	/* don't realloc if asked to do so */
-	if (!pci_realloc_enabled()) {
-		free_list(resource_list_x, &head);
-		goto enable_and_dump;
-	}
+	if (tried_times >= pci_try_num) {
+		if (pci_realloc_enable == undefined)
+			printk(KERN_INFO "Some PCI device resources are unassigned, try booting with pci=realloc\n");
+		else if (pci_realloc_enable == auto_enabled)
+			printk(KERN_INFO "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
 
-	failed_type = 0;
-	for (list = head.next; list;) {
-		failed_type |= list->flags;
-		list = list->next;
-	}
-	/*
-	 * io port are tight, don't try extra
-	 * or if reach the limit, don't want to try more
-	 */
-	failed_type &= type_mask;
-	if ((failed_type == IORESOURCE_IO) || (tried_times >= pci_try_num)) {
-		free_list(resource_list_x, &head);
+		free_list(&fail_head);
 		goto enable_and_dump;
 	}
 
@@ -1172,25 +1396,23 @@ again:
 	 * Try to release leaf bridge's resources that doesn't fit resource of
 	 * child device under that bridge
 	 */
-	for (list = head.next; list;) {
-		bus = list->dev->bus;
-		pci_bus_release_bridge_resources(bus, list->flags & type_mask,
-						  rel_type);
-		list = list->next;
+	list_for_each_entry(fail_res, &fail_head, list) {
+		bus = fail_res->dev->bus;
+		pci_bus_release_bridge_resources(bus,
+						 fail_res->flags & type_mask,
+						 rel_type);
 	}
 	/* restore size and flags */
-	for (list = head.next; list;) {
-		struct resource *res = list->res;
+	list_for_each_entry(fail_res, &fail_head, list) {
+		struct resource *res = fail_res->res;
 
-		res->start = list->start;
-		res->end = list->end;
-		res->flags = list->flags;
-		if (list->dev->subordinate)
+		res->start = fail_res->start;
+		res->end = fail_res->end;
+		res->flags = fail_res->flags;
+		if (fail_res->dev->subordinate)
 			res->flags = 0;
-
-		list = list->next;
 	}
-	free_list(resource_list_x, &head);
+	free_list(&fail_head);
 
 	goto again;
 
@@ -1207,26 +1429,27 @@ enable_and_dump:
 void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
 {
 	struct pci_bus *parent = bridge->subordinate;
+	LIST_HEAD(add_list); /* list of resources that
+					want additional resources */
 	int tried_times = 0;
-	struct resource_list_x head, *list;
+	LIST_HEAD(fail_head);
+	struct pci_dev_resource *fail_res;
 	int retval;
 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
 				  IORESOURCE_PREFETCH;
 
-	head.next = NULL;
-
 again:
-	pci_bus_size_bridges(parent);
-	__pci_bridge_assign_resources(bridge, &head);
-
+	__pci_bus_size_bridges(parent, &add_list);
+	__pci_bridge_assign_resources(bridge, &add_list, &fail_head);
+	BUG_ON(!list_empty(&add_list));
 	tried_times++;
 
-	if (!head.next)
+	if (list_empty(&fail_head))
 		goto enable_all;
 
 	if (tried_times >= 2) {
 		/* still fail, don't need to try more */
-		free_list(resource_list_x, &head);
+		free_list(&fail_head);
 		goto enable_all;
 	}
 
@@ -1237,27 +1460,24 @@ again:
 	 * Try to release leaf bridge's resources that doesn't fit resource of
 	 * child device under that bridge
 	 */
-	for (list = head.next; list;) {
-		struct pci_bus *bus = list->dev->bus;
-		unsigned long flags = list->flags;
+	list_for_each_entry(fail_res, &fail_head, list) {
+		struct pci_bus *bus = fail_res->dev->bus;
+		unsigned long flags = fail_res->flags;
 
 		pci_bus_release_bridge_resources(bus, flags & type_mask,
 						 whole_subtree);
-		list = list->next;
 	}
 	/* restore size and flags */
-	for (list = head.next; list;) {
-		struct resource *res = list->res;
+	list_for_each_entry(fail_res, &fail_head, list) {
+		struct resource *res = fail_res->res;
 
-		res->start = list->start;
-		res->end = list->end;
-		res->flags = list->flags;
-		if (list->dev->subordinate)
+		res->start = fail_res->start;
+		res->end = fail_res->end;
+		res->flags = fail_res->flags;
+		if (fail_res->dev->subordinate)
 			res->flags = 0;
-
-		list = list->next;
 	}
-	free_list(resource_list_x, &head);
+	free_list(&fail_head);
 
 	goto again;
 
@@ -1267,3 +1487,41 @@ enable_all:
 	pci_enable_bridges(parent);
 }
 EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
+
+#ifdef CONFIG_HOTPLUG
+/**
+ * pci_rescan_bus - scan a PCI bus for devices.
+ * @bus: PCI bus to scan
+ *
+ * Scan a PCI bus and child buses for new devices, adds them,
+ * and enables them.
+ *
+ * Returns the max number of subordinate bus discovered.
+ */
+unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
+{
+	unsigned int max;
+	struct pci_dev *dev;
+	LIST_HEAD(add_list); /* list of resources that
+					want additional resources */
+
+	max = pci_scan_child_bus(bus);
+
+	down_read(&pci_bus_sem);
+	list_for_each_entry(dev, &bus->devices, bus_list)
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+		    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+			if (dev->subordinate)
+				__pci_bus_size_bridges(dev->subordinate,
+							 &add_list);
+	up_read(&pci_bus_sem);
+	__pci_bus_assign_resources(bus, &add_list, NULL);
+	BUG_ON(!list_empty(&add_list));
+
+	pci_enable_bridges(bus);
+	pci_bus_add_devices(bus);
+
+	return max;
+}
+EXPORT_SYMBOL_GPL(pci_rescan_bus);
+#endif