mm/memblock.c: refactor functions to set/clear MEMBLOCK_HOTPLUG

There is a lot of duplication in the rubric around actually setting or
clearing a mem region flag.  Create a new helper function to do this and
reduce each of memblock_mark_hotplug() and memblock_clear_hotplug() to a
single line.

This will be useful if someone were to add a new mem region flag - which
I hope to be doing some day soon. But it looks like a plausible cleanup
even without that - so I'd like to get it out of the way now.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Emil Medve <Emilian.Medve@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memblock.c

@@ -715,16 +715,13 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 }
 
 /**
- * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
- * @base: the base phys addr of the region
- * @size: the size of the region
  *
- * This function isolates region [@base, @base + @size), and mark it with flag
- * MEMBLOCK_HOTPLUG.
+ * This function isolates region [@base, @base + @size), and sets/clears flag
  *
  * Return 0 on succees, -errno on failure.
  */
-int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
+static int __init_memblock memblock_setclr_flag(phys_addr_t base,
+				phys_addr_t size, int set, int flag)
 {
 	struct memblock_type *type = &memblock.memory;
 	int i, ret, start_rgn, end_rgn;
@@ -734,37 +731,37 @@ int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
 		return ret;
 
 	for (i = start_rgn; i < end_rgn; i++)
-		memblock_set_region_flags(&type->regions[i], MEMBLOCK_HOTPLUG);
+		if (set)
+			memblock_set_region_flags(&type->regions[i], flag);
+		else
+			memblock_clear_region_flags(&type->regions[i], flag);
 
 	memblock_merge_regions(type);
 	return 0;
 }
 
 /**
- * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
+ * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
  * @base: the base phys addr of the region
  * @size: the size of the region
  *
- * This function isolates region [@base, @base + @size), and clear flag
- * MEMBLOCK_HOTPLUG for the isolated regions.
+ * Return 0 on succees, -errno on failure.
+ */
+int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
+}
+
+/**
+ * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
  *
  * Return 0 on succees, -errno on failure.
  */
 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
 {
-	struct memblock_type *type = &memblock.memory;
-	int i, ret, start_rgn, end_rgn;
-
-	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
-	if (ret)
-		return ret;
-
-	for (i = start_rgn; i < end_rgn; i++)
-		memblock_clear_region_flags(&type->regions[i],
-					    MEMBLOCK_HOTPLUG);
-
-	memblock_merge_regions(type);
-	return 0;
+	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
 }
 
 /**