[PATCH 1/2] drbd: fix rdma dependency

[Arnd Bergmann <arnd@kernel.org>]

From: Arnd Bergmann <arnd@arndb.de>

The new rdma transport module uses a trick to only build support
if infiniband/rdma is enabled. This seems to be done the wrong way
around, as it gets built if RDMA is in a loadable module, but not
if it's built-in.

However, this fails in configurations that have infiniband support
in a loadable module but drbd built-in:

ERROR: modpost: "rdma_bind_addr" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_listen" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_destroy_id" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_destroy_qp" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_disconnect" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "__rdma_create_kernel_id" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_resolve_route" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_reject" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_accept" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!
ERROR: modpost: "rdma_create_qp" [drivers/block/drbd/drbd_transport_rdma.ko] undefined!

Address this by moving the logic from Makefile into Kconfig and
describing the two conditions in which rdma transport can be used
in drbd.

Fixes: 038cb6e644e4 ("drbd: add RDMA transport implementation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/block/drbd/Kconfig  | 5 +++++
 drivers/block/drbd/Makefile | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/block/drbd/Kconfig b/drivers/block/drbd/Kconfig
index 377f0d040031..29ec6ed84251 100644
--- a/drivers/block/drbd/Kconfig
+++ b/drivers/block/drbd/Kconfig
@@ -39,6 +39,11 @@ config BLK_DEV_DRBD
 
 	  If unsure, say N.
 
+config DRBD_TRANSPORT_RDMA
+	tristate
+	depends on RDMA=y || (BLK_DEV_DRBD=RDMA)
+	default BLK_DEV_DRBD
+
 config DRBD_FAULT_INJECTION
 	bool "DRBD fault injection"
 	depends on BLK_DEV_DRBD
diff --git a/drivers/block/drbd/Makefile b/drivers/block/drbd/Makefile
index 99a1cfeed423..caf888235d53 100644
--- a/drivers/block/drbd/Makefile
+++ b/drivers/block/drbd/Makefile
@@ -13,4 +13,4 @@ obj-$(CONFIG_BLK_DEV_DRBD)     += drbd.o
 
 obj-$(CONFIG_BLK_DEV_DRBD)     += drbd_transport_tcp.o
 obj-$(CONFIG_BLK_DEV_DRBD)     += drbd_transport_lb-tcp.o
-obj-$(if $(CONFIG_BLK_DEV_DRBD),$(if $(CONFIG_INFINIBAND),m)) += drbd_transport_rdma.o
+obj-$(CONFIG_DRBD_TRANSPORT_RDMA) += drbd_transport_rdma.o
-- 
2.39.5