bootmem: Replace work_with_active_regions() with for_each_mem_pfn_range()

Callback based iteration is cumbersome and much less useful than
for_each_*() iterator.  This patch implements for_each_mem_pfn_range()
which replaces work_with_active_regions().  All the current users of
work_with_active_regions() are converted.

This simplifies walking over early_node_map and will allow converting
internal logics in page_alloc to use iterator instead of walking
early_node_map directly, which in turn will enable moving node
information to memblock.

powerpc change is only compile tested.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110714074610.GD3455@htj.dyndns.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

2 files changed, 19 insertions, 54 deletions

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 2164006fe170..6f06ea53bca2 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -127,45 +127,25 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn,
 }
 
 /*
- * get_active_region_work_fn - A helper function for get_node_active_region
- *	Returns datax set to the start_pfn and end_pfn if they contain
- *	the initial value of datax->start_pfn between them
- * @start_pfn: start page(inclusive) of region to check
- * @end_pfn: end page(exclusive) of region to check
- * @datax: comes in with ->start_pfn set to value to search for and
- *	goes out with active range if it contains it
- * Returns 1 if search value is in range else 0
- */
-static int __init get_active_region_work_fn(unsigned long start_pfn,
-					unsigned long end_pfn, void *datax)
-{
-	struct node_active_region *data;
-	data = (struct node_active_region *)datax;
-
-	if (start_pfn <= data->start_pfn && end_pfn > data->start_pfn) {
-		data->start_pfn = start_pfn;
-		data->end_pfn = end_pfn;
-		return 1;
-	}
-	return 0;
-
-}
-
-/*
- * get_node_active_region - Return active region containing start_pfn
+ * get_node_active_region - Return active region containing pfn
  * Active range returned is empty if none found.
- * @start_pfn: The page to return the region for.
- * @node_ar: Returned set to the active region containing start_pfn
+ * @pfn: The page to return the region for
+ * @node_ar: Returned set to the active region containing @pfn
  */
-static void __init get_node_active_region(unsigned long start_pfn,
-		       struct node_active_region *node_ar)
+static void __init get_node_active_region(unsigned long pfn,
+					  struct node_active_region *node_ar)
 {
-	int nid = early_pfn_to_nid(start_pfn);
+	unsigned long start_pfn, end_pfn;
+	int i, nid;
 
-	node_ar->nid = nid;
-	node_ar->start_pfn = start_pfn;
-	node_ar->end_pfn = start_pfn;
-	work_with_active_regions(nid, get_active_region_work_fn, node_ar);
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
+		if (pfn >= start_pfn && pfn < end_pfn) {
+			node_ar->nid = nid;
+			node_ar->start_pfn = start_pfn;
+			node_ar->end_pfn = end_pfn;
+			break;
+		}
+	}
 }
 
 static void map_cpu_to_node(int cpu, int node)
diff --git a/arch/x86/mm/memblock.c b/arch/x86/mm/memblock.c
index e126117d1b03..da0d5c84586e 100644
--- a/arch/x86/mm/memblock.c
+++ b/arch/x86/mm/memblock.c
@@ -115,28 +115,13 @@ static void __init memblock_x86_subtract_reserved(struct range *range, int az)
 	memblock_reserve_reserved_regions();
 }
 
-struct count_data {
-	int nr;
-};
-
-static int __init count_work_fn(unsigned long start_pfn,
-				unsigned long end_pfn, void *datax)
-{
-	struct count_data *data = datax;
-
-	data->nr++;
-
-	return 0;
-}
-
 static int __init count_early_node_map(int nodeid)
 {
-	struct count_data data;
-
-	data.nr = 0;
-	work_with_active_regions(nodeid, count_work_fn, &data);
+	int i, cnt = 0;
 
-	return data.nr;
+	for_each_mem_pfn_range(i, nodeid, NULL, NULL, NULL)
+		cnt++;
+	return cnt;
 }
 
 int __init __get_free_all_memory_range(struct range **rangep, int nodeid,