1 files changed, 19 insertions, 67 deletions

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index b0bc023d25c5..d41edd28298b 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -24,8 +24,7 @@
  *
  * Usage of struct page flags:
  *	PG_private: identifies the first component page
- *	PG_private2: identifies the last component page
- *	PG_owner_priv_1: indentifies the huge component page
+ *	PG_owner_priv_1: identifies the huge component page
  *
  */
 
@@ -34,6 +33,7 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <linux/magic.h>
 #include <linux/bitops.h>
 #include <linux/errno.h>
 #include <linux/highmem.h>
@@ -268,10 +268,6 @@ struct zs_pool {
 #endif
 };
 
-/*
- * A zspage's class index and fullness group
- * are encoded in its (first)page->mapping
- */
 #define FULLNESS_BITS	2
 #define CLASS_BITS	8
 #define ISOLATED_BITS	3
@@ -280,7 +276,7 @@ struct zs_pool {
 struct zspage {
 	struct {
 		unsigned int fullness:FULLNESS_BITS;
-		unsigned int class:CLASS_BITS;
+		unsigned int class:CLASS_BITS + 1;
 		unsigned int isolated:ISOLATED_BITS;
 		unsigned int magic:MAGIC_VAL_BITS;
 	};
@@ -364,7 +360,7 @@ static struct zspage *cache_alloc_zspage(struct zs_pool *pool, gfp_t flags)
 {
 	return kmem_cache_alloc(pool->zspage_cachep,
 			flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
-};
+}
 
 static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
 {
@@ -938,7 +934,6 @@ static void reset_page(struct page *page)
 {
 	__ClearPageMovable(page);
 	ClearPagePrivate(page);
-	ClearPagePrivate2(page);
 	set_page_private(page, 0);
 	page_mapcount_reset(page);
 	ClearPageHugeObject(page);
@@ -1085,7 +1080,7 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage,
 	 * 2. each sub-page point to zspage using page->private
 	 *
 	 * we set PG_private to identify the first page (i.e. no other sub-page
-	 * has this flag set) and PG_private_2 to identify the last page.
+	 * has this flag set).
 	 */
 	for (i = 0; i < nr_pages; i++) {
 		page = pages[i];
@@ -1100,8 +1095,6 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage,
 		} else {
 			prev_page->freelist = page;
 		}
-		if (i == nr_pages - 1)
-			SetPagePrivate2(page);
 		prev_page = page;
 	}
 }
@@ -1284,61 +1277,21 @@ out:
 
 #endif /* CONFIG_PGTABLE_MAPPING */
 
-static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action,
-				void *pcpu)
+static int zs_cpu_prepare(unsigned int cpu)
 {
-	int ret, cpu = (long)pcpu;
 	struct mapping_area *area;
 
-	switch (action) {
-	case CPU_UP_PREPARE:
-		area = &per_cpu(zs_map_area, cpu);
-		ret = __zs_cpu_up(area);
-		if (ret)
-			return notifier_from_errno(ret);
-		break;
-	case CPU_DEAD:
-	case CPU_UP_CANCELED:
-		area = &per_cpu(zs_map_area, cpu);
-		__zs_cpu_down(area);
-		break;
-	}
-
-	return NOTIFY_OK;
+	area = &per_cpu(zs_map_area, cpu);
+	return __zs_cpu_up(area);
 }
 
-static struct notifier_block zs_cpu_nb = {
-	.notifier_call = zs_cpu_notifier
-};
-
-static int zs_register_cpu_notifier(void)
+static int zs_cpu_dead(unsigned int cpu)
 {
-	int cpu, uninitialized_var(ret);
-
-	cpu_notifier_register_begin();
-
-	__register_cpu_notifier(&zs_cpu_nb);
-	for_each_online_cpu(cpu) {
-		ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
-		if (notifier_to_errno(ret))
-			break;
-	}
-
-	cpu_notifier_register_done();
-	return notifier_to_errno(ret);
-}
-
-static void zs_unregister_cpu_notifier(void)
-{
-	int cpu;
-
-	cpu_notifier_register_begin();
-
-	for_each_online_cpu(cpu)
-		zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
-	__unregister_cpu_notifier(&zs_cpu_nb);
+	struct mapping_area *area;
 
-	cpu_notifier_register_done();
+	area = &per_cpu(zs_map_area, cpu);
+	__zs_cpu_down(area);
+	return 0;
 }
 
 static void __init init_zs_size_classes(void)
@@ -2423,7 +2376,7 @@ struct zs_pool *zs_create_pool(const char *name)
 		goto err;
 
 	/*
-	 * Iterate reversly, because, size of size_class that we want to use
+	 * Iterate reversely, because, size of size_class that we want to use
 	 * for merging should be larger or equal to current size.
 	 */
 	for (i = zs_size_classes - 1; i >= 0; i--) {
@@ -2534,10 +2487,10 @@ static int __init zs_init(void)
 	if (ret)
 		goto out;
 
-	ret = zs_register_cpu_notifier();
-
+	ret = cpuhp_setup_state(CPUHP_MM_ZS_PREPARE, "mm/zsmalloc:prepare",
+				zs_cpu_prepare, zs_cpu_dead);
 	if (ret)
-		goto notifier_fail;
+		goto hp_setup_fail;
 
 	init_zs_size_classes();
 
@@ -2549,8 +2502,7 @@ static int __init zs_init(void)
 
 	return 0;
 
-notifier_fail:
-	zs_unregister_cpu_notifier();
+hp_setup_fail:
 	zsmalloc_unmount();
 out:
 	return ret;
@@ -2562,7 +2514,7 @@ static void __exit zs_exit(void)
 	zpool_unregister_driver(&zs_zpool_driver);
 #endif
 	zsmalloc_unmount();
-	zs_unregister_cpu_notifier();
+	cpuhp_remove_state(CPUHP_MM_ZS_PREPARE);
 
 	zs_stat_exit();
 }