1 files changed, 102 insertions, 29 deletions

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index fe78189624cf..839a48c3ca27 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -92,6 +92,7 @@
 #include <linux/spinlock.h>
 #include <linux/types.h>
 #include <linux/zsmalloc.h>
+#include <linux/zpool.h>
 
 /*
  * This must be power of 2 and greater than of equal to sizeof(link_free).
@@ -174,7 +175,7 @@ enum fullness_group {
  *	n <= N / f, where
  * n = number of allocated objects
  * N = total number of objects zspage can store
- * f = 1/fullness_threshold_frac
+ * f = fullness_threshold_frac
  *
  * Similarly, we assign zspage to:
  *	ZS_ALMOST_FULL	when n > N / f
@@ -198,9 +199,6 @@ struct size_class {
 
 	spinlock_t lock;
 
-	/* stats */
-	u64 pages_allocated;
-
 	struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS];
 };
 
@@ -219,6 +217,7 @@ struct zs_pool {
 	struct size_class size_class[ZS_SIZE_CLASSES];
 
 	gfp_t flags;	/* allocation flags used when growing pool */
+	atomic_long_t pages_allocated;
 };
 
 /*
@@ -240,6 +239,82 @@ struct mapping_area {
 	enum zs_mapmode vm_mm; /* mapping mode */
 };
 
+/* zpool driver */
+
+#ifdef CONFIG_ZPOOL
+
+static void *zs_zpool_create(gfp_t gfp, struct zpool_ops *zpool_ops)
+{
+	return zs_create_pool(gfp);
+}
+
+static void zs_zpool_destroy(void *pool)
+{
+	zs_destroy_pool(pool);
+}
+
+static int zs_zpool_malloc(void *pool, size_t size, gfp_t gfp,
+			unsigned long *handle)
+{
+	*handle = zs_malloc(pool, size);
+	return *handle ? 0 : -1;
+}
+static void zs_zpool_free(void *pool, unsigned long handle)
+{
+	zs_free(pool, handle);
+}
+
+static int zs_zpool_shrink(void *pool, unsigned int pages,
+			unsigned int *reclaimed)
+{
+	return -EINVAL;
+}
+
+static void *zs_zpool_map(void *pool, unsigned long handle,
+			enum zpool_mapmode mm)
+{
+	enum zs_mapmode zs_mm;
+
+	switch (mm) {
+	case ZPOOL_MM_RO:
+		zs_mm = ZS_MM_RO;
+		break;
+	case ZPOOL_MM_WO:
+		zs_mm = ZS_MM_WO;
+		break;
+	case ZPOOL_MM_RW: /* fallthru */
+	default:
+		zs_mm = ZS_MM_RW;
+		break;
+	}
+
+	return zs_map_object(pool, handle, zs_mm);
+}
+static void zs_zpool_unmap(void *pool, unsigned long handle)
+{
+	zs_unmap_object(pool, handle);
+}
+
+static u64 zs_zpool_total_size(void *pool)
+{
+	return zs_get_total_pages(pool) << PAGE_SHIFT;
+}
+
+static struct zpool_driver zs_zpool_driver = {
+	.type =		"zsmalloc",
+	.owner =	THIS_MODULE,
+	.create =	zs_zpool_create,
+	.destroy =	zs_zpool_destroy,
+	.malloc =	zs_zpool_malloc,
+	.free =		zs_zpool_free,
+	.shrink =	zs_zpool_shrink,
+	.map =		zs_zpool_map,
+	.unmap =	zs_zpool_unmap,
+	.total_size =	zs_zpool_total_size,
+};
+
+MODULE_ALIAS("zpool-zsmalloc");
+#endif /* CONFIG_ZPOOL */
 
 /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
 static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
@@ -553,7 +628,7 @@ static void init_zspage(struct page *first_page, struct size_class *class)
 	while (page) {
 		struct page *next_page;
 		struct link_free *link;
-		unsigned int i, objs_on_page;
+		unsigned int i = 1;
 
 		/*
 		 * page->index stores offset of first object starting
@@ -566,14 +641,10 @@ static void init_zspage(struct page *first_page, struct size_class *class)
 
 		link = (struct link_free *)kmap_atomic(page) +
 						off / sizeof(*link);
-		objs_on_page = (PAGE_SIZE - off) / class->size;
 
-		for (i = 1; i <= objs_on_page; i++) {
-			off += class->size;
-			if (off < PAGE_SIZE) {
-				link->next = obj_location_to_handle(page, i);
-				link += class->size / sizeof(*link);
-			}
+		while ((off += class->size) < PAGE_SIZE) {
+			link->next = obj_location_to_handle(page, i++);
+			link += class->size / sizeof(*link);
 		}
 
 		/*
@@ -585,7 +656,7 @@ static void init_zspage(struct page *first_page, struct size_class *class)
 		link->next = obj_location_to_handle(next_page, 0);
 		kunmap_atomic(link);
 		page = next_page;
-		off = (off + class->size) % PAGE_SIZE;
+		off %= PAGE_SIZE;
 	}
 }
 
@@ -690,7 +761,7 @@ static inline void __zs_cpu_down(struct mapping_area *area)
 static inline void *__zs_map_object(struct mapping_area *area,
 				struct page *pages[2], int off, int size)
 {
-	BUG_ON(map_vm_area(area->vm, PAGE_KERNEL, &pages));
+	BUG_ON(map_vm_area(area->vm, PAGE_KERNEL, pages));
 	area->vm_addr = area->vm->addr;
 	return area->vm_addr + off;
 }
@@ -814,6 +885,10 @@ static void zs_exit(void)
 {
 	int cpu;
 
+#ifdef CONFIG_ZPOOL
+	zpool_unregister_driver(&zs_zpool_driver);
+#endif
+
 	cpu_notifier_register_begin();
 
 	for_each_online_cpu(cpu)
@@ -840,6 +915,10 @@ static int zs_init(void)
 
 	cpu_notifier_register_done();
 
+#ifdef CONFIG_ZPOOL
+	zpool_register_driver(&zs_zpool_driver);
+#endif
+
 	return 0;
 fail:
 	zs_exit();
@@ -943,8 +1022,9 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
 			return 0;
 
 		set_zspage_mapping(first_page, class->index, ZS_EMPTY);
+		atomic_long_add(class->pages_per_zspage,
+					&pool->pages_allocated);
 		spin_lock(&class->lock);
-		class->pages_allocated += class->pages_per_zspage;
 	}
 
 	obj = (unsigned long)first_page->freelist;
@@ -997,14 +1077,13 @@ void zs_free(struct zs_pool *pool, unsigned long obj)
 
 	first_page->inuse--;
 	fullness = fix_fullness_group(pool, first_page);
-
-	if (fullness == ZS_EMPTY)
-		class->pages_allocated -= class->pages_per_zspage;
-
 	spin_unlock(&class->lock);
 
-	if (fullness == ZS_EMPTY)
+	if (fullness == ZS_EMPTY) {
+		atomic_long_sub(class->pages_per_zspage,
+				&pool->pages_allocated);
 		free_zspage(first_page);
+	}
 }
 EXPORT_SYMBOL_GPL(zs_free);
 
@@ -1098,17 +1177,11 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
 }
 EXPORT_SYMBOL_GPL(zs_unmap_object);
 
-u64 zs_get_total_size_bytes(struct zs_pool *pool)
+unsigned long zs_get_total_pages(struct zs_pool *pool)
 {
-	int i;
-	u64 npages = 0;
-
-	for (i = 0; i < ZS_SIZE_CLASSES; i++)
-		npages += pool->size_class[i].pages_allocated;
-
-	return npages << PAGE_SHIFT;
+	return atomic_long_read(&pool->pages_allocated);
 }
-EXPORT_SYMBOL_GPL(zs_get_total_size_bytes);
+EXPORT_SYMBOL_GPL(zs_get_total_pages);
 
 module_init(zs_init);
 module_exit(zs_exit);