PCI: Refactor pbus_size_mem()

The original idea comes from Ram Pai.  This patch puts the chunk of
code for calculating the minimal alignment of memory window into a
separate inline function.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index a66cf09..1e808ca 100644 (file)
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -812,6 +812,28 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
        }
 }
 
+static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
+                                                 int max_order)
+{
+       resource_size_t align = 0;
+       resource_size_t min_align = 0;
+       int order;
+
+       for (order = 0; order <= max_order; order++) {
+               resource_size_t align1 = 1;
+
+               align1 <<= (order + 20);
+
+               if (!align)
+                       min_align = align1;
+               else if (ALIGN(align + min_align, min_align) < align1)
+                       min_align = align1 >> 1;
+               align += aligns[order];
+       }
+
+       return min_align;
+}
+
 /**
  * pbus_size_mem() - size the memory window of a given bus
  *
@@ -891,20 +913,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                children_add_size += get_res_add_size(realloc_head, r);
                }
        }
-       align = 0;
-       min_align = 0;
-       for (order = 0; order <= max_order; order++) {
-               resource_size_t align1 = 1;
-
-               align1 <<= (order + 20);
-
-               if (!align)
-                       min_align = align1;
-               else if (ALIGN(align + min_align, min_align) < align1)
-                       min_align = align1 >> 1;
-               align += aligns[order];
-       }
 
+       min_align = calculate_mem_align(aligns, max_order);
        min_align = max(min_align, window_alignment(bus, b_res->flags & mask));
        size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
        if (children_add_size > add_size)