Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6

[pandora-kernel.git] / drivers / pci / bus.c

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 7f0af0e..172bf26 100644 (file)
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -64,6 +64,49 @@ void pci_bus_remove_resources(struct pci_bus *bus)
        }
 }
 
+/*
+ * Find the highest-address bus resource below the cursor "res".  If the
+ * cursor is NULL, return the highest resource.
+ */
+static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus,
+                                                  unsigned int type,
+                                                  struct resource *res)
+{
+       struct resource *r, *prev = NULL;
+       int i;
+
+       pci_bus_for_each_resource(bus, r, i) {
+               if (!r)
+                       continue;
+
+               if ((r->flags & IORESOURCE_TYPE_BITS) != type)
+                       continue;
+
+               /* If this resource is at or past the cursor, skip it */
+               if (res) {
+                       if (r == res)
+                               continue;
+                       if (r->end > res->end)
+                               continue;
+                       if (r->end == res->end && r->start > res->start)
+                               continue;
+               }
+
+               if (!prev)
+                       prev = r;
+
+               /*
+                * A small resource is higher than a large one that ends at
+                * the same address.
+                */
+               if (r->end > prev->end ||
+                   (r->end == prev->end && r->start > prev->start))
+                       prev = r;
+       }
+
+       return prev;
+}
+
 /**
  * pci_bus_alloc_resource - allocate a resource from a parent bus
  * @bus: PCI bus
@@ -89,9 +132,10 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
                                          resource_size_t),
                void *alignf_data)
 {
-       int i, ret = -ENOMEM;
+       int ret = -ENOMEM;
        struct resource *r;
        resource_size_t max = -1;
+       unsigned int type = res->flags & IORESOURCE_TYPE_BITS;
 
        type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 
@@ -99,10 +143,9 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
        if (!(res->flags & IORESOURCE_MEM_64))
                max = PCIBIOS_MAX_MEM_32;
 
-       pci_bus_for_each_resource(bus, r, i) {
-               if (!r)
-                       continue;
-
+       /* Look for space at highest addresses first */
+       r = pci_bus_find_resource_prev(bus, type, NULL);
+       for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) {
                /* type_mask must match */
                if ((res->flags ^ r->flags) & type_mask)
                        continue;