resources: factor out resource_clip() to simplify find_resource()

[linux-2.6-microblaze.git] / kernel / resource.c

diff --git a/kernel/resource.c b/kernel/resource.c
index 7b36976..26e9f25 100644 (file)
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -357,6 +357,23 @@ int __weak page_is_ram(unsigned long pfn)
        return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
 }
 
+static resource_size_t simple_align_resource(void *data,
+                                            const struct resource *avail,
+                                            resource_size_t size,
+                                            resource_size_t align)
+{
+       return avail->start;
+}
+
+static void resource_clip(struct resource *res, resource_size_t min,
+                         resource_size_t max)
+{
+       if (res->start < min)
+               res->start = min;
+       if (res->end > max)
+               res->end = max;
+}
+
 /*
  * Find empty slot in the resource tree given range and alignment.
  */
@@ -386,13 +403,11 @@ static int find_resource(struct resource *root, struct resource *new,
                        tmp.end = this->start - 1;
                else
                        tmp.end = root->end;
-               if (tmp.start < min)
-                       tmp.start = min;
-               if (tmp.end > max)
-                       tmp.end = max;
+
+               resource_clip(&tmp, min, max);
                tmp.start = ALIGN(tmp.start, align);
-               if (alignf)
-                       tmp.start = alignf(alignf_data, &tmp, size, align);
+
+               tmp.start = alignf(alignf_data, &tmp, size, align);
                if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) {
                        new->start = tmp.start;
                        new->end = tmp.start + size - 1;
@@ -428,6 +443,9 @@ int allocate_resource(struct resource *root, struct resource *new,
 {
        int err;
 
+       if (!alignf)
+               alignf = simple_align_resource;
+
        write_lock(&resource_lock);
        err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
        if (err >= 0 && __request_resource(root, new))