memblock, x86: Replace __get_free_all_memory_range() with for_each_free_mem_range()

__get_free_all_memory_range() walks memblock, calculates free memory
areas and fills in the specified range.  It can be easily replaced
with for_each_free_mem_range().

Convert free_low_memory_core_early() and
add_highpages_with_active_regions() to for_each_free_mem_range().
This leaves __get_free_all_memory_range() without any user.  Kill it
and related functions.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-10-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/include/asm/memblock.h

@@ -5,9 +5,6 @@
 
 void memblock_x86_reserve_range(u64 start, u64 end, char *name);
 void memblock_x86_free_range(u64 start, u64 end);
-struct range;
-int __get_free_all_memory_range(struct range **range, int nodeid,
-			 unsigned long start_pfn, unsigned long end_pfn);
 
 u64 memblock_x86_hole_size(u64 start, u64 end);
 u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit);

arch/x86/mm/init_32.c

@@ -427,23 +427,17 @@ static void __init add_one_highpage_init(struct page *page)
 void __init add_highpages_with_active_regions(int nid,
 			 unsigned long start_pfn, unsigned long end_pfn)
 {
-	struct range *range;
-	int nr_range;
-	int i;
-
-	nr_range = __get_free_all_memory_range(&range, nid, start_pfn, end_pfn);
-
-	for (i = 0; i < nr_range; i++) {
-		struct page *page;
-		int node_pfn;
-
-		for (node_pfn = range[i].start; node_pfn < range[i].end;
-		     node_pfn++) {
-			if (!pfn_valid(node_pfn))
-				continue;
-			page = pfn_to_page(node_pfn);
-			add_one_highpage_init(page);
-		}
+	phys_addr_t start, end;
+	u64 i;
+
+	for_each_free_mem_range(i, nid, &start, &end, NULL) {
+		unsigned long pfn = clamp_t(unsigned long, PFN_UP(start),
+					    start_pfn, end_pfn);
+		unsigned long e_pfn = clamp_t(unsigned long, PFN_DOWN(end),
+					      start_pfn, end_pfn);
+		for ( ; pfn < e_pfn; pfn++)
+			if (pfn_valid(pfn))
+				add_one_highpage_init(pfn_to_page(pfn));
 	}
 }
 #else

arch/x86/mm/memblock.c

@@ -30,65 +30,6 @@ static __init struct range *find_range_array(int count)
 	return range;
 }
 
-static void __init memblock_x86_subtract_reserved(struct range *range, int az)
-{
-	u64 final_start, final_end;
-	struct memblock_region *r;
-
-	/* Take out region array itself at first*/
-	memblock_free_reserved_regions();
-
-	memblock_dbg("Subtract (%ld early reservations)\n", memblock.reserved.cnt);
-
-	for_each_memblock(reserved, r) {
-		memblock_dbg("  [%010llx-%010llx]\n", (u64)r->base, (u64)r->base + r->size - 1);
-		final_start = PFN_DOWN(r->base);
-		final_end = PFN_UP(r->base + r->size);
-		if (final_start >= final_end)
-			continue;
-		subtract_range(range, az, final_start, final_end);
-	}
-
-	/* Put region array back ? */
-	memblock_reserve_reserved_regions();
-}
-
-static int __init count_early_node_map(int nodeid)
-{
-	int i, cnt = 0;
-
-	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,
-			 unsigned long start_pfn, unsigned long end_pfn)
-{
-	int count;
-	struct range *range;
-	int nr_range;
-
-	count = (memblock.reserved.cnt + count_early_node_map(nodeid)) * 2;
-
-	range = find_range_array(count);
-	nr_range = 0;
-
-	/*
-	 * Use early_node_map[] and memblock.reserved.region to get range array
-	 * at first
-	 */
-	nr_range = add_from_early_node_map(range, count, nr_range, nodeid);
-	subtract_range(range, count, 0, start_pfn);
-	subtract_range(range, count, end_pfn, -1ULL);
-
-	memblock_x86_subtract_reserved(range, count);
-	nr_range = clean_sort_range(range, count);
-
-	*rangep = range;
-	return nr_range;
-}
-
 static u64 __init __memblock_x86_memory_in_range(u64 addr, u64 limit, bool get_free)
 {
 	int i, count;

mm/nobootmem.c

@@ -108,21 +108,25 @@ static void __init __free_pages_memory(unsigned long start, unsigned long end)
 
 unsigned long __init free_low_memory_core_early(int nodeid)
 {
-	int i;
-	u64 start, end;
 	unsigned long count = 0;
-	struct range *range = NULL;
-	int nr_range;
-
-	nr_range = __get_free_all_memory_range(&range, nodeid, 0, max_low_pfn);
-
-	for (i = 0; i < nr_range; i++) {
-		start = range[i].start;
-		end = range[i].end;
-		count += end - start;
-		__free_pages_memory(start, end);
+	phys_addr_t start, end;
+	u64 i;
+
+	/* free reserved array temporarily so that it's treated as free area */
+	memblock_free_reserved_regions();
+
+	for_each_free_mem_range(i, MAX_NUMNODES, &start, &end, NULL) {
+		unsigned long start_pfn = PFN_UP(start);
+		unsigned long end_pfn = min_t(unsigned long,
+					      PFN_DOWN(end), max_low_pfn);
+		if (start_pfn < end_pfn) {
+			__free_pages_memory(start_pfn, end_pfn);
+			count += end_pfn - start_pfn;
+		}
 	}
 
+	/* put region array back? */
+	memblock_reserve_reserved_regions();
 	return count;
 }