[PATCH 2/3] zsmalloc: add compaction and huge class callbacks

[Vitaly Wool <vitalywool@gmail.com>]

Add compaction callbacks for zpool compaction API extension.
Add huge_class_size callback too to be fully aligned.

With these in place, we can proceed with ZRAM modification
to use the universal (zpool) API. 

Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
---
 mm/zsmalloc.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 2b2b9aae8a3c..43f43272b998 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -437,11 +437,29 @@ static void zs_zpool_unmap(void *pool, unsigned long handle)
 	zs_unmap_object(pool, handle);
 }
 
+static unsigned long zs_zpool_compact(void *pool)
+{
+	return zs_compact(pool);
+}
+
+static unsigned long zs_zpool_get_compacted(void *pool)
+{
+	struct zs_pool_stats stats;
+
+	zs_pool_stats(pool, &stats);
+	return stats.pages_compacted;
+}
+
 static u64 zs_zpool_total_size(void *pool)
 {
 	return zs_get_total_pages(pool) << PAGE_SHIFT;
 }
 
+static size_t zs_zpool_huge_class_size(void *pool)
+{
+	return zs_huge_class_size(pool);
+}
+
 static struct zpool_driver zs_zpool_driver = {
 	.type =			  "zsmalloc",
 	.owner =		  THIS_MODULE,
@@ -453,6 +471,9 @@ static struct zpool_driver zs_zpool_driver = {
 	.map =			  zs_zpool_map,
 	.unmap =		  zs_zpool_unmap,
 	.total_size =		  zs_zpool_total_size,
+	.compact =		  zs_zpool_compact,
+	.get_num_compacted =	  zs_zpool_get_compacted,
+	.huge_class_size =	  zs_zpool_huge_class_size,
 };
 
 MODULE_ALIAS("zpool-zsmalloc");
-- 
2.20.1