Introduce QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY

Check whether the disable-legacy property is present on the following
devices:
  virtio-balloon-pci
  virtio-blk-pci
  virtio-scsi-pci
  virtio-serial-pci
  virtio-9p-pci
  virtio-net-pci
  virtio-rng-pci
  virtio-gpu-pci
  virtio-input-host-pci
  virtio-keyboard-pci
  virtio-mouse-pci
  virtio-tablet-pci

Assuming that if QEMU knows other virtio devices where this property
is applicable, it will have at least one of these devices.

Added in QEMU by:
commit e266d421490e0ae83044bbebb209b2d3650c0ba6
    virtio-pci: add flags to enable/disable legacy/modern

src/qemu/qemu_capabilities.c

@@ -340,6 +340,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               "display", /* 230 */
               "intel-iommu",
               "smm",
+              "virtio-pci-disable-legacy",
     );
 
 
@@ -1741,6 +1742,34 @@ static struct virQEMUCapsObjectTypeProps virQEMUCapsObjectProps[] = {
       ARRAY_CARDINALITY(virQEMUCapsObjectPropsUSBNECXHCI) },
 };
 
+struct virQEMUCapsPropTypeObjects {
+    const char *prop;
+    int flag;
+    const char **objects;
+};
+
+static const char *virQEMUCapsVirtioPCIDisableLegacyObjects[] = {
+     "virtio-balloon-pci",
+     "virtio-blk-pci",
+     "virtio-scsi-pci",
+     "virtio-serial-pci",
+     "virtio-9p-pci",
+     "virtio-net-pci",
+     "virtio-rng-pci",
+     "virtio-gpu-pci",
+     "virtio-input-host-pci",
+     "virtio-keyboard-pci",
+     "virtio-mouse-pci",
+     "virtio-tablet-pci",
+     NULL
+};
+
+static struct virQEMUCapsPropTypeObjects virQEMUCapsPropObjects[] = {
+    { "disable-legacy",
+      QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY,
+      virQEMUCapsVirtioPCIDisableLegacyObjects }
+};
+
 
 static void
 virQEMUCapsProcessStringFlags(virQEMUCapsPtr qemuCaps,
@@ -1761,6 +1790,31 @@ virQEMUCapsProcessStringFlags(virQEMUCapsPtr qemuCaps,
 }
 
 
+static void
+virQEMUCapsProcessProps(virQEMUCapsPtr qemuCaps,
+                        size_t nprops,
+                        struct virQEMUCapsPropTypeObjects *props,
+                        const char *object,
+                        size_t nvalues,
+                        char *const*values)
+{
+    size_t i, j;
+
+    for (i = 0; i < nprops; i++) {
+        if (virQEMUCapsGet(qemuCaps, props[i].flag))
+            continue;
+
+        for (j = 0; j < nvalues; j++) {
+            if (STREQ(values[j], props[i].prop)) {
+                if (virStringArrayHasString(props[i].objects, object))
+                    virQEMUCapsSet(qemuCaps, props[i].flag);
+                break;
+            }
+        }
+    }
+}
+
+
 static void
 virQEMUCapsFreeStringList(size_t len,
                           char **values)
@@ -2470,6 +2524,10 @@ virQEMUCapsProbeQMPObjects(virQEMUCapsPtr qemuCaps,
                                       virQEMUCapsObjectProps[i].nprops,
                                       virQEMUCapsObjectProps[i].props,
                                       nvalues, values);
+        virQEMUCapsProcessProps(qemuCaps,
+                                ARRAY_CARDINALITY(virQEMUCapsPropObjects),
+                                virQEMUCapsPropObjects, type,
+                                nvalues, values);
         virQEMUCapsFreeStringList(nvalues, values);
     }
 

src/qemu/qemu_capabilities.h

@@ -373,6 +373,7 @@ typedef enum {
     QEMU_CAPS_DISPLAY, /* -display */
     QEMU_CAPS_DEVICE_INTEL_IOMMU, /* -device intel-iommu */
     QEMU_CAPS_MACHINE_SMM_OPT, /* -machine xxx,smm=on/off/auto */
+    QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY, /* virtio-*pci.disable-legacy */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

tests/qemucapabilitiesdata/caps_2.4.0.x86_64.xml

@@ -184,6 +184,7 @@
   <flag name='display'/>
   <flag name='intel-iommu'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2004000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.5.0.x86_64.xml

@@ -189,6 +189,7 @@
   <flag name='display'/>
   <flag name='intel-iommu'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2005000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0-gicv2.aarch64.xml

@@ -158,6 +158,7 @@
   <flag name='tls-creds-x509'/>
   <flag name='display'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0-gicv3.aarch64.xml

@@ -158,6 +158,7 @@
   <flag name='tls-creds-x509'/>
   <flag name='display'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0.ppc64le.xml

@@ -152,6 +152,7 @@
   <flag name='tls-creds-x509'/>
   <flag name='display'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0.x86_64.xml

@@ -195,6 +195,7 @@
   <flag name='display'/>
   <flag name='intel-iommu'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2006000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.7.0.x86_64.xml

@@ -192,6 +192,7 @@
   <flag name='display'/>
   <flag name='intel-iommu'/>
   <flag name='smm'/>
+  <flag name='virtio-pci-disable-legacy'/>
   <version>2006091</version>
   <kvmVersion>0</kvmVersion>
   <package> (v2.7.0-rc1-52-g42e0d60)</package>