diff options
| -rw-r--r-- | include/linux/zpool.h | 2 | ||||
| -rw-r--r-- | mm/zpool.c | 33 |
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) |