[PATCH V2 1/2] zpool: Add malloc_support_movable to zpool_driver

From: Hui Zhu
Date: Sun Jun 02 2019 - 05:50:25 EST


As a zpool_driver, zsmalloc can allocate movable memory because it
support migate pages.
But zbud and z3fold cannot allocate movable memory.

This commit adds malloc_support_movable to zpool_driver.
If a zpool_driver support allocate movable memory, set it to true.
And add zpool_malloc_support_movable check malloc_support_movable
to make sure if a zpool support allocate movable memory.

Signed-off-by: Hui Zhu <teawaterz@xxxxxxxxxxxxxxxxx>
---
include/linux/zpool.h | 3 +++
mm/zpool.c | 16 ++++++++++++++++
mm/zsmalloc.c | 19 ++++++++++---------
3 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/include/linux/zpool.h b/include/linux/zpool.h
index 7238865e75b0..51bf43076165 100644
--- a/include/linux/zpool.h
+++ b/include/linux/zpool.h
@@ -46,6 +46,8 @@ const char *zpool_get_type(struct zpool *pool);

void zpool_destroy_pool(struct zpool *pool);

+bool zpool_malloc_support_movable(struct zpool *pool);
+
int zpool_malloc(struct zpool *pool, size_t size, gfp_t gfp,
unsigned long *handle);

@@ -90,6 +92,7 @@ struct zpool_driver {
struct zpool *zpool);
void (*destroy)(void *pool);

+ bool malloc_support_movable;
int (*malloc)(void *pool, size_t size, gfp_t gfp,
unsigned long *handle);
void (*free)(void *pool, unsigned long handle);
diff --git a/mm/zpool.c b/mm/zpool.c
index a2dd9107857d..863669212070 100644
--- a/mm/zpool.c
+++ b/mm/zpool.c
@@ -238,6 +238,22 @@ const char *zpool_get_type(struct zpool *zpool)
return zpool->driver->type;
}

+/**
+ * zpool_malloc_support_movable() - Check if the zpool support
+ * allocate movable memory
+ * @zpool: The zpool to check
+ *
+ * This returns if the zpool support allocate movable memory.
+ *
+ * Implementations must guarantee this to be thread-safe.
+ *
+ * Returns: true if if the zpool support allocate movable memory, false if not
+ */
+bool zpool_malloc_support_movable(struct zpool *zpool)
+{
+ return zpool->driver->malloc_support_movable;
+}
+
/**
* zpool_malloc() - Allocate memory
* @zpool: The zpool to allocate from.
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 0787d33b80d8..8f3d9a4d46f4 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -437,15 +437,16 @@ static u64 zs_zpool_total_size(void *pool)
}

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,
- .map = zs_zpool_map,
- .unmap = zs_zpool_unmap,
- .total_size = zs_zpool_total_size,
+ .type = "zsmalloc",
+ .owner = THIS_MODULE,
+ .create = zs_zpool_create,
+ .destroy = zs_zpool_destroy,
+ .malloc_support_movable = true,
+ .malloc = zs_zpool_malloc,
+ .free = zs_zpool_free,
+ .map = zs_zpool_map,
+ .unmap = zs_zpool_unmap,
+ .total_size = zs_zpool_total_size,
};

MODULE_ALIAS("zpool-zsmalloc");
--
2.20.1 (Apple Git-117)