[PATCH v2] xen: fix build without pci passthrough

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

has_igd_gfx_passthru is only available when QEMU is built with
CONFIG_XEN_PCI_PASSTHROUGH, and hence shouldn't be used in common
code without checking if it's available.

Fixes: 46472d82322d0 ('xen: convert "-machine igd-passthru" to an accelerator 
property')
Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Anthony Perard <anthony.perard@xxxxxxxxxx>
Cc: Paul Durrant <paul@xxxxxxx>
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
---
Changes since v1:
 - Do not include osdep in header file.
 - Always add the setters/getters of igd-passthru, report an error
   when attempting to set igd-passthru without built in
   pci-passthrough support.
---
 hw/xen/xen-common.c | 4 ++++
 hw/xen/xen_pt.h     | 6 ++++++
 2 files changed, 10 insertions(+)

diff --git a/hw/xen/xen-common.c b/hw/xen/xen-common.c
index 70564cc952..d758770da0 100644
--- a/hw/xen/xen-common.c
+++ b/hw/xen/xen-common.c
@@ -134,7 +134,11 @@ static bool xen_get_igd_gfx_passthru(Object *obj, Error 
**errp)
 
 static void xen_set_igd_gfx_passthru(Object *obj, bool value, Error **errp)
 {
+#ifdef CONFIG_XEN_PCI_PASSTHROUGH
     has_igd_gfx_passthru = value;
+#else
+    error_setg(errp, "Xen PCI passthrough support not built in");
+#endif
 }
 
 static void xen_setup_post(MachineState *ms, AccelState *accel)
diff --git a/hw/xen/xen_pt.h b/hw/xen/xen_pt.h
index 179775db7b..7430235a27 100644
--- a/hw/xen/xen_pt.h
+++ b/hw/xen/xen_pt.h
@@ -322,7 +322,13 @@ extern void *pci_assign_dev_load_option_rom(PCIDevice *dev,
                                             unsigned int domain,
                                             unsigned int bus, unsigned int 
slot,
                                             unsigned int function);
+
+#ifdef CONFIG_XEN_PCI_PASSTHROUGH
 extern bool has_igd_gfx_passthru;
+#else
+# define has_igd_gfx_passthru false
+#endif
+
 static inline bool is_igd_vga_passthrough(XenHostPCIDevice *dev)
 {
     return (has_igd_gfx_passthru
-- 
2.26.2