diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index f11b839166ef6f010bb15971f235ead5475e4540..0f260a6e97c44addbf8120d131e4afb1fb3cabb9 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -70,6 +70,14 @@ #define RBD_IMAGE_ID_LEN_MAX 64 #define RBD_OBJ_PREFIX_LEN_MAX 64 +/* Feature bits */ + +#define RBD_FEATURE_LAYERING 1 + +/* Features supported by this (client software) implementation. */ + +#define RBD_FEATURES_ALL (0) + /* * An RBD device name will be "rbd#", where the "rbd" comes from * RBD_DRV_NAME above, and # is a unique integer identifier. @@ -2226,6 +2234,7 @@ static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, __le64 features; __le64 incompat; } features_buf = { 0 }; + u64 incompat; int ret; ret = rbd_req_sync_exec(rbd_dev, rbd_dev->header_name, @@ -2236,6 +2245,11 @@ static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, dout("%s: rbd_req_sync_exec returned %d\n", __func__, ret); if (ret < 0) return ret; + + incompat = le64_to_cpu(features_buf.incompat); + if (incompat & ~RBD_FEATURES_ALL) + return -ENOTSUPP; + *snap_features = le64_to_cpu(features_buf.features); dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n", @@ -2977,7 +2991,7 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) if (ret < 0) goto out_err; - /* Get the features for the image */ + /* Get the and check features for the image */ ret = rbd_dev_v2_features(rbd_dev); if (ret < 0)