caps: Add new capability for the bps/iops throttling length

Add the capability to detect if the qemu binary can support the feature
to use bps-max-length and friends.

src/qemu/qemu_capabilities.c

@@ -346,6 +346,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               "virtio-net.rx_queue_size", /* 235 */
               "machine-iommu",
               "virtio-vga",
+              "drive-iotune-max-length",
     );
 
 
@@ -2843,6 +2844,7 @@ static struct virQEMUCapsCommandLineProps virQEMUCapsCommandLine[] = {
     { "name", "debug-threads", QEMU_CAPS_NAME_DEBUG_THREADS },
     { "name", "guest", QEMU_CAPS_NAME_GUEST },
     { "spice", "unix", QEMU_CAPS_SPICE_UNIX },
+    { "drive", "throttling.bps-total-max-length", QEMU_CAPS_DRIVE_IOTUNE_MAX_LENGTH },
 };
 
 static int

src/qemu/qemu_capabilities.h

@@ -380,6 +380,7 @@ typedef enum {
     QEMU_CAPS_VIRTIO_NET_RX_QUEUE_SIZE, /* virtio-net-*.rx_queue_size */
     QEMU_CAPS_MACHINE_IOMMU, /* -machine iommu=on */
     QEMU_CAPS_DEVICE_VIRTIO_VGA, /* -device virtio-vga */
+    QEMU_CAPS_DRIVE_IOTUNE_MAX_LENGTH, /* -drive bps_max_length = and friends */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

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

@@ -158,6 +158,7 @@
   <flag name='display'/>
   <flag name='smm'/>
   <flag name='virtio-pci-disable-legacy'/>
+  <flag name='drive-iotune-max-length'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

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

@@ -158,6 +158,7 @@
   <flag name='display'/>
   <flag name='smm'/>
   <flag name='virtio-pci-disable-legacy'/>
+  <flag name='drive-iotune-max-length'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0.ppc64le.xml

@@ -153,6 +153,7 @@
   <flag name='smm'/>
   <flag name='virtio-pci-disable-legacy'/>
   <flag name='virtio-vga'/>
+  <flag name='drive-iotune-max-length'/>
   <version>2005094</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.6.0.x86_64.xml

@@ -192,6 +192,7 @@
   <flag name='virtio-pci-disable-legacy'/>
   <flag name='machine-iommu'/>
   <flag name='virtio-vga'/>
+  <flag name='drive-iotune-max-length'/>
   <version>2006000</version>
   <kvmVersion>0</kvmVersion>
   <package></package>

tests/qemucapabilitiesdata/caps_2.7.0.x86_64.xml

@@ -193,6 +193,7 @@
   <flag name='virtio-pci-disable-legacy'/>
   <flag name='query-hotpluggable-cpus'/>
   <flag name='virtio-vga'/>
+  <flag name='drive-iotune-max-length'/>
   <version>2007000</version>
   <kvmVersion>0</kvmVersion>
   <package> (v2.7.0)</package>