qemu: Support disk model=virtio-{non-}transitional

Add new <disk> model values for virtio transitional devices. When
combined with bus='virtio':

* "virtio-transitional" maps to qemu "virtio-blk-pci-transitional"
* "virtio-non-transitional" maps to qemu "virtio-blk-pci-non-transitional"
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

src/qemu/qemu_command.c

@@ -423,13 +423,14 @@ qemuBuildDeviceAddressStr(virBufferPtr buf,
 static int
 qemuBuildVirtioDevStr(virBufferPtr buf,
                       const char *baseName,
-                      virQEMUCapsPtr qemuCaps ATTRIBUTE_UNUSED,
+                      virQEMUCapsPtr qemuCaps,
                       virDomainDeviceType devtype,
                       void *devdata)
 {
     const char *implName = NULL;
     virDomainDeviceDef device = { .type = devtype };
     virDomainDeviceInfoPtr info;
+    bool has_tmodel, has_ntmodel;
 
     virDomainDeviceSetData(&device, devdata);
     info = virDomainDeviceGetInfo(&device);
@@ -471,6 +472,78 @@ qemuBuildVirtioDevStr(virBufferPtr buf,
 
     virBufferAsprintf(buf, "%s-%s", baseName, implName);
 
+    switch (devtype) {
+        case VIR_DOMAIN_DEVICE_DISK:
+            has_tmodel = device.data.disk->model == VIR_DOMAIN_DISK_MODEL_VIRTIO_TRANSITIONAL;
+            has_ntmodel = device.data.disk->model == VIR_DOMAIN_DISK_MODEL_VIRTIO_NON_TRANSITIONAL;
+            break;
+
+        case VIR_DOMAIN_DEVICE_NET:
+        case VIR_DOMAIN_DEVICE_LEASE:
+        case VIR_DOMAIN_DEVICE_FS:
+        case VIR_DOMAIN_DEVICE_INPUT:
+        case VIR_DOMAIN_DEVICE_SOUND:
+        case VIR_DOMAIN_DEVICE_VIDEO:
+        case VIR_DOMAIN_DEVICE_HOSTDEV:
+        case VIR_DOMAIN_DEVICE_WATCHDOG:
+        case VIR_DOMAIN_DEVICE_CONTROLLER:
+        case VIR_DOMAIN_DEVICE_GRAPHICS:
+        case VIR_DOMAIN_DEVICE_HUB:
+        case VIR_DOMAIN_DEVICE_REDIRDEV:
+        case VIR_DOMAIN_DEVICE_NONE:
+        case VIR_DOMAIN_DEVICE_SMARTCARD:
+        case VIR_DOMAIN_DEVICE_CHR:
+        case VIR_DOMAIN_DEVICE_MEMBALLOON:
+        case VIR_DOMAIN_DEVICE_NVRAM:
+        case VIR_DOMAIN_DEVICE_SHMEM:
+        case VIR_DOMAIN_DEVICE_TPM:
+        case VIR_DOMAIN_DEVICE_PANIC:
+        case VIR_DOMAIN_DEVICE_RNG:
+        case VIR_DOMAIN_DEVICE_MEMORY:
+        case VIR_DOMAIN_DEVICE_IOMMU:
+        case VIR_DOMAIN_DEVICE_VSOCK:
+        case VIR_DOMAIN_DEVICE_LAST:
+        default:
+            return 0;
+    }
+
+    if (info->type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI &&
+        (has_tmodel || has_ntmodel)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("virtio (non-)transitional models are not "
+                         "supported for address type=%s"),
+                       virDomainDeviceAddressTypeToString(info->type));
+        return -1;
+    }
+
+    if (has_tmodel) {
+        if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_PCI_TRANSITIONAL)) {
+            virBufferAddLit(buf, "-transitional");
+        } else if (virQEMUCapsGet(qemuCaps,
+                                  QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY)) {
+            virBufferAddLit(buf, ",disable-legacy=off,disable-modern=off");
+        }
+        /* No error if -transitional is not supported: our address
+         * allocation will force the device into plain PCI bus, which
+         * is functionally identical to standard 'virtio-XXX' behavior
+         */
+    } else if (has_ntmodel) {
+        if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_PCI_TRANSITIONAL)) {
+            virBufferAddLit(buf, "-non-transitional");
+        } else if (virQEMUCapsGet(qemuCaps,
+                                  QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY)) {
+            /* Even if the QEMU binary doesn't support the non-transitional
+             * device, we can still make it work by manually disabling legacy
+             * VirtIO and enabling modern VirtIO */
+            virBufferAddLit(buf, ",disable-legacy=on,disable-modern=off");
+        } else {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("virtio non-transitional model not supported "
+                             "for this qemu"));
+            return -1;
+        }
+    }
+
     return 0;
 }
 

src/qemu/qemu_domain_address.c

@@ -720,7 +720,19 @@ qemuDomainDeviceCalculatePCIConnectFlags(virDomainDeviceDefPtr dev,
     case VIR_DOMAIN_DEVICE_DISK:
         switch ((virDomainDiskBus) dev->data.disk->bus) {
         case VIR_DOMAIN_DISK_BUS_VIRTIO:
-            return virtioFlags; /* only virtio disks use PCI */
+            /* only virtio disks use PCI */
+            switch ((virDomainDiskModel) dev->data.disk->model) {
+            case VIR_DOMAIN_DISK_MODEL_VIRTIO_TRANSITIONAL:
+                /* Transitional devices only work in conventional PCI slots */
+                return pciFlags;
+            case VIR_DOMAIN_DISK_MODEL_VIRTIO:
+            case VIR_DOMAIN_DISK_MODEL_VIRTIO_NON_TRANSITIONAL:
+            case VIR_DOMAIN_DISK_MODEL_DEFAULT:
+                return virtioFlags;
+            case VIR_DOMAIN_DISK_MODEL_LAST:
+                break;
+            }
+            return 0;
 
         case VIR_DOMAIN_DISK_BUS_IDE:
         case VIR_DOMAIN_DISK_BUS_FDC:

tests/qemuxml2argvdata/virtio-non-transitional.x86_64-3.1.0.args

@@ -27,8 +27,8 @@ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
 addr=0x1 \
 -device pcie-root-port,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x1.0x1 \
 -drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-virtio-disk0 \
--device virtio-blk-pci,scsi=off,bus=pci.1,addr=0x0,drive=drive-virtio-disk0,\
-id=virtio-disk0,bootindex=1 \
+-device virtio-blk-pci,disable-legacy=on,disable-modern=off,scsi=off,bus=pci.1,\
+addr=0x0,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
 resourcecontrol=deny \
 -msg timestamp=on

tests/qemuxml2argvdata/virtio-non-transitional.x86_64-latest.args

@@ -27,8 +27,8 @@ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
 addr=0x1 \
 -device pcie-root-port,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x1.0x1 \
 -drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-virtio-disk0 \
--device virtio-blk-pci,scsi=off,bus=pci.1,addr=0x0,drive=drive-virtio-disk0,\
-id=virtio-disk0,bootindex=1 \
+-device virtio-blk-pci-non-transitional,scsi=off,bus=pci.1,addr=0x0,\
+drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
 resourcecontrol=deny \
 -msg timestamp=on

tests/qemuxml2argvdata/virtio-transitional.x86_64-3.1.0.args

@@ -25,10 +25,11 @@ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
 -boot strict=on \
 -device pcie-root-port,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,\
 addr=0x1 \
--device pcie-root-port,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x1.0x1 \
+-device pcie-pci-bridge,id=pci.2,bus=pci.1,addr=0x0 \
+-device pcie-root-port,port=0x9,chassis=3,id=pci.3,bus=pcie.0,addr=0x1.0x1 \
 -drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-virtio-disk0 \
--device virtio-blk-pci,scsi=off,bus=pci.1,addr=0x0,drive=drive-virtio-disk0,\
-id=virtio-disk0,bootindex=1 \
+-device virtio-blk-pci,disable-legacy=off,disable-modern=off,scsi=off,\
+bus=pci.2,addr=0x1,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
 resourcecontrol=deny \
 -msg timestamp=on

tests/qemuxml2argvdata/virtio-transitional.x86_64-latest.args

@@ -25,10 +25,11 @@ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
 -boot strict=on \
 -device pcie-root-port,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,\
 addr=0x1 \
--device pcie-root-port,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x1.0x1 \
+-device pcie-pci-bridge,id=pci.2,bus=pci.1,addr=0x0 \
+-device pcie-root-port,port=0x9,chassis=3,id=pci.3,bus=pcie.0,addr=0x1.0x1 \
 -drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-virtio-disk0 \
--device virtio-blk-pci,scsi=off,bus=pci.1,addr=0x0,drive=drive-virtio-disk0,\
-id=virtio-disk0,bootindex=1 \
+-device virtio-blk-pci-transitional,scsi=off,bus=pci.2,addr=0x1,\
+drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
 resourcecontrol=deny \
 -msg timestamp=on

tests/qemuxml2xmloutdata/virtio-transitional.xml

@@ -18,7 +18,7 @@
       <driver name='qemu' type='raw'/>
       <source dev='/dev/HostVG/QEMUGuest1'/>
       <target dev='vda' bus='virtio'/>
-      <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
+      <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/>
     </disk>
     <controller type='usb' index='0' model='none'/>
     <controller type='sata' index='0'>
@@ -30,9 +30,13 @@
       <target chassis='1' port='0x8'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0' multifunction='on'/>
     </controller>
-    <controller type='pci' index='2' model='pcie-root-port'>
+    <controller type='pci' index='2' model='pcie-to-pci-bridge'>
+      <model name='pcie-pci-bridge'/>
+      <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
+    </controller>
+    <controller type='pci' index='3' model='pcie-root-port'>
       <model name='pcie-root-port'/>
-      <target chassis='2' port='0x9'/>
+      <target chassis='3' port='0x9'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
     </controller>
     <input type='mouse' bus='ps2'/>