vfio: Move vfio_kvm_device_add/del_fd() to helpers.c

vfio_kvm_device_add/del_fd() are low level routines. Move them with
the other helpers.

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: John Levon <john.levon@nutanix.com>
Link: https://lore.kernel.org/qemu-devel/20250318095415.670319-18-clg@redhat.com
Link: https://lore.kernel.org/qemu-devel/20250326075122.1299361-19-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

hw/vfio/common.c

@@ -1333,64 +1333,6 @@ void vfio_reset_handler(void *opaque)
     }
 }
 
-int vfio_kvm_device_add_fd(int fd, Error **errp)
-{
-#ifdef CONFIG_KVM
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_VFIO_FILE,
-        .attr = KVM_DEV_VFIO_FILE_ADD,
-        .addr = (uint64_t)(unsigned long)&fd,
-    };
-
-    if (!kvm_enabled()) {
-        return 0;
-    }
-
-    if (vfio_kvm_device_fd < 0) {
-        struct kvm_create_device cd = {
-            .type = KVM_DEV_TYPE_VFIO,
-        };
-
-        if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
-            error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
-            return -errno;
-        }
-
-        vfio_kvm_device_fd = cd.fd;
-    }
-
-    if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
-        error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
-                         fd);
-        return -errno;
-    }
-#endif
-    return 0;
-}
-
-int vfio_kvm_device_del_fd(int fd, Error **errp)
-{
-#ifdef CONFIG_KVM
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_VFIO_FILE,
-        .attr = KVM_DEV_VFIO_FILE_DEL,
-        .addr = (uint64_t)(unsigned long)&fd,
-    };
-
-    if (vfio_kvm_device_fd < 0) {
-        error_setg(errp, "KVM VFIO device isn't created yet");
-        return -EINVAL;
-    }
-
-    if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
-        error_setg_errno(errp, errno,
-                         "Failed to remove fd %d from KVM VFIO device", fd);
-        return -errno;
-    }
-#endif
-    return 0;
-}
-
 struct vfio_device_info *vfio_get_device_info(int fd)
 {
     struct vfio_device_info *info;

hw/vfio/helpers.c

@@ -22,6 +22,7 @@
 #include "qemu/osdep.h"
 #include <sys/ioctl.h>
 
+#include "system/kvm.h"
 #include "hw/vfio/vfio-common.h"
 #include "hw/vfio/pci.h"
 #include "hw/hw.h"
@@ -253,6 +254,64 @@ bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
     return true;
 }
 
+int vfio_kvm_device_add_fd(int fd, Error **errp)
+{
+#ifdef CONFIG_KVM
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_VFIO_FILE,
+        .attr = KVM_DEV_VFIO_FILE_ADD,
+        .addr = (uint64_t)(unsigned long)&fd,
+    };
+
+    if (!kvm_enabled()) {
+        return 0;
+    }
+
+    if (vfio_kvm_device_fd < 0) {
+        struct kvm_create_device cd = {
+            .type = KVM_DEV_TYPE_VFIO,
+        };
+
+        if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
+            error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
+            return -errno;
+        }
+
+        vfio_kvm_device_fd = cd.fd;
+    }
+
+    if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
+        error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
+                         fd);
+        return -errno;
+    }
+#endif
+    return 0;
+}
+
+int vfio_kvm_device_del_fd(int fd, Error **errp)
+{
+#ifdef CONFIG_KVM
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_VFIO_FILE,
+        .attr = KVM_DEV_VFIO_FILE_DEL,
+        .addr = (uint64_t)(unsigned long)&fd,
+    };
+
+    if (vfio_kvm_device_fd < 0) {
+        error_setg(errp, "KVM VFIO device isn't created yet");
+        return -EINVAL;
+    }
+
+    if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
+        error_setg_errno(errp, errno,
+                         "Failed to remove fd %d from KVM VFIO device", fd);
+        return -errno;
+    }
+#endif
+    return 0;
+}
+
 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
                              uint32_t subtype, struct vfio_region_info **info)
 {

hw/vfio/iommufd.c

@@ -26,6 +26,7 @@
 #include "qemu/chardev_open.h"
 #include "pci.h"
 #include "vfio-iommufd.h"
+#include "vfio-helpers.h"
 
 #define TYPE_HOST_IOMMU_DEVICE_IOMMUFD_VFIO             \
             TYPE_HOST_IOMMU_DEVICE_IOMMUFD "-vfio"

hw/vfio/meson.build

@@ -2,6 +2,7 @@ vfio_ss = ss.source_set()
 vfio_ss.add(files(
   'common.c',
   'container.c',
+  'helpers.c',
 ))
 vfio_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr.c'))
 vfio_ss.add(when: 'CONFIG_VFIO_PCI', if_true: files(
@@ -18,7 +19,6 @@ specific_ss.add_all(when: 'CONFIG_VFIO', if_true: vfio_ss)
 system_ss.add(when: 'CONFIG_VFIO_XGMAC', if_true: files('calxeda-xgmac.c'))
 system_ss.add(when: 'CONFIG_VFIO_AMD_XGBE', if_true: files('amd-xgbe.c'))
 system_ss.add(when: 'CONFIG_VFIO', if_true: files(
-  'helpers.c',
   'container-base.c',
   'migration.c',
   'migration-multifd.c',

hw/vfio/vfio-helpers.h

@@ -26,4 +26,7 @@ bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
 
 int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size);
 
+int vfio_kvm_device_add_fd(int fd, Error **errp);
+int vfio_kvm_device_del_fd(int fd, Error **errp);
+
 #endif /* HW_VFIO_VFIO_HELPERS_H */

include/hw/vfio/vfio-common.h

@@ -130,9 +130,6 @@ bool vfio_attach_device(char *name, VFIODevice *vbasedev,
 void vfio_detach_device(VFIODevice *vbasedev);
 VFIODevice *vfio_get_vfio_device(Object *obj);
 
-int vfio_kvm_device_add_fd(int fd, Error **errp);
-int vfio_kvm_device_del_fd(int fd, Error **errp);
-
 bool vfio_cpr_register_container(VFIOContainerBase *bcontainer, Error **errp);
 void vfio_cpr_unregister_container(VFIOContainerBase *bcontainer);