vfio/pci: introduce CONFIG_VFIO_PCI_ZDEV_KVM

The current contents of vfio-pci-zdev are today only useful in a KVM
environment; let's tie everything currently under vfio-pci-zdev to
this Kconfig statement and require KVM in this case, reducing complexity
(e.g. symbol lookups).

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-11-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
index 4da1914..f9d0c90 100644 (file)
--- a/drivers/vfio/pci/Kconfig
+++ b/drivers/vfio/pci/Kconfig
@@ -44,6 +44,17 @@ config VFIO_PCI_IGD
          To enable Intel IGD assignment through vfio-pci, say Y.
 endif
 
+config VFIO_PCI_ZDEV_KVM
+       bool "VFIO PCI extensions for s390x KVM passthrough"
+       depends on S390 && KVM
+       default y
+       help
+         Support s390x-specific extensions to enable support for enhancements
+         to KVM passthrough capabilities, such as interpretive execution of
+         zPCI instructions.
+
+         To enable s390x KVM vfio-pci extensions, say Y.
+
 source "drivers/vfio/pci/mlx5/Kconfig"
 
 source "drivers/vfio/pci/hisilicon/Kconfig"

diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile
index 7052ebd..24c5242 100644 (file)
--- a/drivers/vfio/pci/Makefile
+++ b/drivers/vfio/pci/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
 vfio-pci-core-y := vfio_pci_core.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o
-vfio-pci-core-$(CONFIG_S390) += vfio_pci_zdev.o
+vfio-pci-core-$(CONFIG_VFIO_PCI_ZDEV_KVM) += vfio_pci_zdev.o
 obj-$(CONFIG_VFIO_PCI_CORE) += vfio-pci-core.o
 
 vfio-pci-y := vfio_pci.o

diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h
index 23c176d..63af289 100644 (file)
--- a/include/linux/vfio_pci_core.h
+++ b/include/linux/vfio_pci_core.h
@@ -206,7 +206,7 @@ static inline int vfio_pci_igd_init(struct vfio_pci_core_device *vdev)
 }
 #endif
 
-#ifdef CONFIG_S390
+#ifdef CONFIG_VFIO_PCI_ZDEV_KVM
 extern int vfio_pci_info_zdev_add_caps(struct vfio_pci_core_device *vdev,
                                       struct vfio_info_cap *caps);
 #else