[libvirt] [PATCHv3 6/6] qemu: format caching-mode on iommu command line

[Ján Tomko]

Format the caching-mode option for the intel-iommu device,
based on its <driver caching> attribute value.

https://bugzilla.redhat.com/show_bug.cgi?id=1427005
---
 src/qemu/qemu_capabilities.c                       |  3 +++
 src/qemu/qemu_capabilities.h                       |  3 +++
 src/qemu/qemu_command.c                            | 11 ++++++++++
 tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml   |  1 +
 .../qemuxml2argv-intel-iommu-caching.args          | 25 ++++++++++++++++++++++
 tests/qemuxml2argvtest.c                           | 11 ++++++++++
 6 files changed, 54 insertions(+)
 create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-intel-iommu-caching.args

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 0c7d7b1..0e9afd2 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -366,6 +366,8 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               "query-named-block-nodes",
               "kernel-irqchip",
               "intel-iommu-intremap",
+
+              "intel-iommu-caching", /* 255 */
     );
 
 
@@ -1718,6 +1720,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsObjectPropsUSBNECXHCI[] = {
 
 static struct virQEMUCapsStringFlags virQEMUCapsObjectPropsIntelIOMMU[] = {
     { "intremap", QEMU_CAPS_INTEL_IOMMU_INTREMAP },
+    { "caching-mode", QEMU_CAPS_INTEL_IOMMU_CACHING },
 };
 
 /* see documentation for virQEMUCapsQMPSchemaGetByPath for the query format */
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index 4d19691..a3ff7e6 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -404,6 +404,9 @@ typedef enum {
     QEMU_CAPS_MACHINE_KERNEL_IRQCHIP, /* -machine kernel_irqchip */
     QEMU_CAPS_INTEL_IOMMU_INTREMAP, /* intel-iommu.intremap */
 
+    /* 255 */
+    QEMU_CAPS_INTEL_IOMMU_CACHING, /* intel-iommu.caching-mode */
+
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;
 
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 07c4aeb..566bd87 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6690,6 +6690,13 @@ qemuBuildIOMMUCommandLine(virCommandPtr cmd,
                              "with this QEMU binary"));
             return -1;
         }
+        if (iommu->caching != VIR_TRISTATE_SWITCH_ABSENT &&
+            !virQEMUCapsGet(qemuCaps, QEMU_CAPS_INTEL_IOMMU_CACHING))  {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("iommu: caching mode is not supported "
+                             "with this QEMU binary"));
+            return -1;
+        }
         break;
     case VIR_DOMAIN_IOMMU_MODEL_LAST:
         break;
@@ -6719,6 +6726,10 @@ qemuBuildIOMMUCommandLine(virCommandPtr cmd,
             virBufferAsprintf(&opts, ",intremap=%s",
                               virTristateSwitchTypeToString(iommu->intremap));
         }
+        if (iommu->caching != VIR_TRISTATE_SWITCH_ABSENT) {
+            virBufferAsprintf(&opts, ",caching-mode=%s",
+                              virTristateSwitchTypeToString(iommu->caching));
+        }
     case VIR_DOMAIN_IOMMU_MODEL_LAST:
         break;
     }
diff --git a/tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml
index 799c52a..0193492 100644
--- a/tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml
+++ b/tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml
@@ -209,6 +209,7 @@
   <flag name='query-named-block-nodes'/>
   <flag name='kernel-irqchip'/>
   <flag name='intel-iommu-intremap'/>
+  <flag name='intel-iommu-caching'/>
   <version>2008090</version>
   <kvmVersion>0</kvmVersion>
   <package> (v2.9.0-rc0-142-g940a8ce)</package>
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-intel-iommu-caching.args b/tests/qemuxml2argvdata/qemuxml2argv-intel-iommu-caching.args
new file mode 100644
index 0000000..1bec6d0
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-intel-iommu-caching.args
@@ -0,0 +1,25 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-x86_64 \
+-name QEMUGuest1 \
+-S \
+-machine q35,accel=tcg \
+-m 214 \
+-smp 1,sockets=1,cores=1,threads=1 \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-nographic \
+-nodefaults \
+-monitor unix:/tmp/lib/domain--1-QEMUGuest1/monitor.sock,server,nowait \
+-no-acpi \
+-boot c \
+-device intel-iommu,intremap=on,caching-mode=on \
+-device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x1e \
+-device pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x0 \
+-device ioh3420,port=0x10,chassis=3,id=pci.3,bus=pcie.0,addr=0x2 \
+-device ich9-usb-ehci1,id=usb,bus=pci.2,addr=0x2.0x7 \
+-device rtl8139,vlan=0,id=net0,mac=52:54:00:ab:0c:5c,bus=pci.2,addr=0x1 \
+-net user,vlan=0,name=hostnet0
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 29cd8b5..aab20c4 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -2497,6 +2497,17 @@ mymain(void)
             QEMU_CAPS_MACHINE_KERNEL_IRQCHIP,
             QEMU_CAPS_INTEL_IOMMU_INTREMAP,
             QEMU_CAPS_DEVICE_INTEL_IOMMU);
+    DO_TEST("intel-iommu-caching",
+            QEMU_CAPS_MACHINE_OPT,
+            QEMU_CAPS_DEVICE_PCI_BRIDGE,
+            QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE,
+            QEMU_CAPS_DEVICE_IOH3420,
+            QEMU_CAPS_ICH9_AHCI,
+            QEMU_CAPS_PCI_MULTIFUNCTION,
+            QEMU_CAPS_ICH9_USB_EHCI1,
+            QEMU_CAPS_DEVICE_INTEL_IOMMU,
+            QEMU_CAPS_INTEL_IOMMU_INTREMAP,
+            QEMU_CAPS_INTEL_IOMMU_CACHING);
 
     DO_TEST("cpu-hotplug-startup", QEMU_CAPS_QUERY_HOTPLUGGABLE_CPUS);
 
-- 
2.10.2