vhost: refine vhost and vringh kconfig

Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
not necessarily for VM since it's a generic userspace and kernel
communication protocol. Such dependency may prevent archs without
virtualization support from using vhost.

To solve this, a dedicated vhost menu is created under drivers so
CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.

While at it, also squash Kconfig.vringh into vhost Kconfig file. This
avoids the trick of conditional inclusion from VOP or CAIF. Then it
will be easier to introduce new vringh users and common dependency for
both vringh and vhost.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

5 files changed, 23 insertions, 21 deletions

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 8befa53f43be..7a6d8b2b68b4 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
 
 source "drivers/virtio/Kconfig"
 
+source "drivers/vhost/Kconfig"
+
 source "drivers/hv/Kconfig"
 
 source "drivers/xen/Kconfig"
diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
index b6841ba6d922..8f201d019f5a 100644
--- a/drivers/misc/mic/Kconfig
+++ b/drivers/misc/mic/Kconfig
@@ -133,8 +133,4 @@ config VOP
 	  OS and tools for MIC to use with this driver are available from
 	  <http://software.intel.com/en-us/mic-developer>.
 
-if VOP
-source "drivers/vhost/Kconfig.vringh"
-endif
-
 endmenu
diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
index e74e2bb61236..9db0570c5beb 100644
--- a/drivers/net/caif/Kconfig
+++ b/drivers/net/caif/Kconfig
@@ -58,8 +58,4 @@ config CAIF_VIRTIO
 	---help---
 	  The CAIF driver for CAIF over Virtio.
 
-if CAIF_VIRTIO
-source "drivers/vhost/Kconfig.vringh"
-endif
-
 endif # CAIF_DRIVERS
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 3d03ccbd1adc..e775beddc36a 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -1,4 +1,23 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config VHOST_RING
+	tristate
+	help
+	  This option is selected by any driver which needs to access
+	  the host side of a virtio ring.
+
+config VHOST
+	tristate
+	select VHOST_IOTLB
+	help
+	  This option is selected by any driver which needs to access
+	  the core of vhost.
+
+menuconfig VHOST_MENU
+	bool "VHOST drivers"
+	default y
+
+if VHOST_MENU
+
 config VHOST_NET
 	tristate "Host kernel accelerator for virtio net"
 	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
@@ -23,8 +42,8 @@ config VHOST_SCSI
 config VHOST_VSOCK
 	tristate "vhost virtio-vsock driver"
 	depends on VSOCKETS && EVENTFD
-	select VIRTIO_VSOCKETS_COMMON
 	select VHOST
+	select VIRTIO_VSOCKETS_COMMON
 	default n
 	---help---
 	This kernel module can be loaded in the host kernel to provide AF_VSOCK
@@ -34,12 +53,6 @@ config VHOST_VSOCK
 	To compile this driver as a module, choose M here: the module will be called
 	vhost_vsock.
 
-config VHOST
-	tristate
-	---help---
-	  This option is selected by any driver which needs to access
-	  the core of vhost.
-
 config VHOST_CROSS_ENDIAN_LEGACY
 	bool "Cross-endian support for vhost"
 	default n
@@ -54,3 +67,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
 	  adds some overhead, it is disabled by default.
 
 	  If unsure, say "N".
+endif
diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
deleted file mode 100644
index c1fe36a9b8d4..000000000000
--- a/drivers/vhost/Kconfig.vringh
+++ /dev/null
@@ -1,6 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-only
-config VHOST_RING
-	tristate
-	---help---
-	  This option is selected by any driver which needs to access
-	  the host side of a virtio ring.