2 files changed, 35 insertions, 0 deletions

diff --git a/include/linux/zpool.h b/include/linux/zpool.h
index c924a28d9805..42f8ec992452 100644
--- a/include/linux/zpool.h
+++ b/include/linux/zpool.h
@@ -36,6 +36,8 @@ enum zpool_mapmode {
         ZPOOL_MM_DEFAULT = ZPOOL_MM_RW
 };
 
+bool zpool_has_pool(char *type);
+
 struct zpool *zpool_create_pool(char *type, char *name,
                         gfp_t gfp, const struct zpool_ops *ops);
 
diff --git a/mm/zpool.c b/mm/zpool.c
index 68d2dd8ed2d8..8f670d3e8706 100644
--- a/mm/zpool.c
+++ b/mm/zpool.c
@@ -100,6 +100,39 @@ static void zpool_put_driver(struct zpool_driver *driver)
 }
 
 /**
+ * zpool_has_pool() - Check if the pool driver is available
+ * @type        The type of the zpool to check (e.g. zbud, zsmalloc)
+ *
+ * This checks if the @type pool driver is available.  This will try to load
+ * the requested module, if needed, but there is no guarantee the module will
+ * still be loaded and available immediately after calling.  If this returns
+ * true, the caller should assume the pool is available, but must be prepared
+ * to handle the @zpool_create_pool() returning failure.  However if this
+ * returns false, the caller should assume the requested pool type is not
+ * available; either the requested pool type module does not exist, or could
+ * not be loaded, and calling @zpool_create_pool() with the pool type will
+ * fail.
+ *
+ * Returns: true if @type pool is available, false if not
+ */
+bool zpool_has_pool(char *type)
+{
+        struct zpool_driver *driver = zpool_get_driver(type);
+
+        if (!driver) {
+                request_module("zpool-%s", type);
+                driver = zpool_get_driver(type);
+        }
+
+        if (!driver)
+                return false;
+
+        zpool_put_driver(driver);
+        return true;
+}
+EXPORT_SYMBOL(zpool_has_pool);
+
+/**
  * zpool_create_pool() - Create a new zpool
  * @type        The type of the zpool to create (e.g. zbud, zsmalloc)
  * @name        The name of the zpool (e.g. zram0, zswap)