vfio: Introduce a new header file for helper services

Gather all helper routine declarations into "vfio-helpers.h" to reduce
exposure of VFIO internals in "hw/vfio/vfio-common.h".

Reviewed-by: John Levon <john.levon@nutanix.com>
Link: https://lore.kernel.org/qemu-devel/20250318095415.670319-16-clg@redhat.com
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Link: https://lore.kernel.org/qemu-devel/20250326075122.1299361-17-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

8 files changed, 32 insertions, 7 deletions

diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c
index 748a51f..aaf9131 100644
--- a/hw/s390x/s390-pci-vfio.c
+++ b/hw/s390x/s390-pci-vfio.c
@@ -21,6 +21,7 @@
 #include "hw/s390x/s390-pci-vfio.h"
 #include "hw/vfio/pci.h"
 #include "hw/vfio/vfio-container.h"
+#include "hw/vfio/vfio-helpers.h"
 
 /*
  * Get the current DMA available count from vfio.  Returns true if vfio is
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index c099d4d..18e5aac 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -44,6 +44,7 @@
 #include "system/tcg.h"
 #include "system/tpm.h"
 #include "vfio-migration-internal.h"
+#include "vfio-helpers.h"
 
 VFIODeviceList vfio_device_list =
     QLIST_HEAD_INITIALIZER(vfio_device_list);
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 6ef53ee..b2d72f5 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -33,6 +33,7 @@
 #include "qapi/error.h"
 #include "pci.h"
 #include "hw/vfio/vfio-container.h"
+#include "vfio-helpers.h"
 
 #define TYPE_HOST_IOMMU_DEVICE_LEGACY_VFIO TYPE_HOST_IOMMU_DEVICE "-legacy-vfio"
 
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index 8940394..054ee6e 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -30,6 +30,7 @@
 #include "qemu/error-report.h"
 #include "qemu/units.h"
 #include "monitor/monitor.h"
+#include "vfio-helpers.h"
 
 /*
  * Common VFIO interrupt disable
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index b0aac2f..bade3b8 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -45,6 +45,7 @@
 #include "migration/qemu-file.h"
 #include "system/iommufd.h"
 #include "vfio-migration-internal.h"
+#include "vfio-helpers.h"
 
 #define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug"
 
diff --git a/hw/vfio/region.c b/hw/vfio/region.c
index 08cd69e..9049143 100644
--- a/hw/vfio/region.c
+++ b/hw/vfio/region.c
@@ -29,6 +29,7 @@
 #include "qemu/error-report.h"
 #include "qemu/units.h"
 #include "monitor/monitor.h"
+#include "vfio-helpers.h"
 
 /*
  * IO Port/MMIO - Beware of the endians, VFIO is always little endian
diff --git a/hw/vfio/vfio-helpers.h b/hw/vfio/vfio-helpers.h
new file mode 100644
index 0000000..d7e4dcb
--- /dev/null
+++ b/hw/vfio/vfio-helpers.h
@@ -0,0 +1,26 @@
+/*
+ * VFIO helpers
+ *
+ * Copyright Red Hat, Inc. 2025
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef HW_VFIO_VFIO_HELPERS_H
+#define HW_VFIO_VFIO_HELPERS_H
+
+#ifdef CONFIG_LINUX
+#include <linux/vfio.h>
+
+struct vfio_info_cap_header *
+vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id);
+struct vfio_info_cap_header *
+vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id);
+struct vfio_info_cap_header *
+vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id);
+
+#endif
+
+int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size);
+
+#endif /* HW_VFIO_VFIO_HELPERS_H */
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index bb11b82..8e46511 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -147,17 +147,10 @@ int vfio_get_region_info(VFIODevice *vbasedev, int index,
 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
                              uint32_t subtype, struct vfio_region_info **info);
 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type);
-struct vfio_info_cap_header *
-vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id);
 bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
                              unsigned int *avail);
-struct vfio_info_cap_header *
-vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id);
-struct vfio_info_cap_header *
-vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id);
 #endif
 
-int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size);
 bool vfio_devices_all_dirty_tracking_started(
     const VFIOContainerBase *bcontainer);
 bool