generic: add phys_addr_t for holding physical addresses

[linux-2.6-omap-h63xx.git] / kernel / resource.c

diff --git a/kernel/resource.c b/kernel/resource.c
index 03d796c1b2e980c1ea55c5f1dc3bbfed64b0233e..fc59dcc4795b772c9aae54f266d50d9a79703db2 100644 (file)
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -516,6 +516,70 @@ int adjust_resource(struct resource *res, resource_size_t start, resource_size_t
        return result;
 }
 
+static void __init __reserve_region_with_split(struct resource *root,
+               resource_size_t start, resource_size_t end,
+               const char *name)
+{
+       struct resource *parent = root;
+       struct resource *conflict;
+       struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
+
+       if (!res)
+               return;
+
+       res->name = name;
+       res->start = start;
+       res->end = end;
+       res->flags = IORESOURCE_BUSY;
+
+       for (;;) {
+               conflict = __request_resource(parent, res);
+               if (!conflict)
+                       break;
+               if (conflict != parent) {
+                       parent = conflict;
+                       if (!(conflict->flags & IORESOURCE_BUSY))
+                               continue;
+               }
+
+               /* Uhhuh, that didn't work out.. */
+               kfree(res);
+               res = NULL;
+               break;
+       }
+
+       if (!res) {
+               /* failed, split and try again */
+
+               /* conflict covered whole area */
+               if (conflict->start <= start && conflict->end >= end)
+                       return;
+
+               if (conflict->start > start)
+                       __reserve_region_with_split(root, start, conflict->start-1, name);
+               if (!(conflict->flags & IORESOURCE_BUSY)) {
+                       resource_size_t common_start, common_end;
+
+                       common_start = max(conflict->start, start);
+                       common_end = min(conflict->end, end);
+                       if (common_start < common_end)
+                               __reserve_region_with_split(root, common_start, common_end, name);
+               }
+               if (conflict->end < end)
+                       __reserve_region_with_split(root, conflict->end+1, end, name);
+       }
+
+}
+
+void reserve_region_with_split(struct resource *root,
+               resource_size_t start, resource_size_t end,
+               const char *name)
+{
+       write_lock(&resource_lock);
+       __reserve_region_with_split(root, start, end, name);
+       write_unlock(&resource_lock);
+}
+
 EXPORT_SYMBOL(adjust_resource);
 
 /**