qemu-command: introduce new vgamem attribute for QXL video device

Add attribute to set vgamem_mb parameter of QXL device for QEMU. This
value sets the size of VGA framebuffer for QXL device. Default value in
QEMU is 8MB so reuse it also in libvirt to not break things.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1076098

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>

docs/formatdomain.html.in

@@ -4732,7 +4732,10 @@ qemu-kvm -net nic,model=? /dev/null
           only and specifies the size of the primary bar, while the optional
           attribute <code>vram</code> specifies the secondary bar size.
           If "ram" or "vram" are not supplied a default value is used. The ram
-          should also be rounded to power of two as vram.
+          should also be rounded to power of two as vram. There is also optional
+          attribute <code>vgamem</code> (<span class="since">since 1.2.11 (QEMU
+          only)</span>) to set the size of VGA framebuffer for fallback mode of
+          QXL device.
         </p>
       </dd>
 

docs/schemas/domaincommon.rng

@@ -2877,6 +2877,11 @@
                   <ref name="unsignedInt"/>
                 </attribute>
               </optional>
+              <optional>
+                <attribute name="vgamem">
+                  <ref name="unsignedInt"/>
+                </attribute>
+              </optional>
             </group>
           </choice>
           <optional>

src/conf/domain_conf.c

@@ -10272,6 +10272,7 @@ virDomainVideoDefParseXML(xmlNodePtr node,
     char *heads = NULL;
     char *vram = NULL;
     char *ram = NULL;
+    char *vgamem = NULL;
     char *primary = NULL;
 
     if (VIR_ALLOC(def) < 0)
@@ -10285,6 +10286,7 @@ virDomainVideoDefParseXML(xmlNodePtr node,
                 type = virXMLPropString(cur, "type");
                 ram = virXMLPropString(cur, "ram");
                 vram = virXMLPropString(cur, "vram");
+                vgamem = virXMLPropString(cur, "vgamem");
                 heads = virXMLPropString(cur, "heads");
 
                 if ((primary = virXMLPropString(cur, "primary")) != NULL) {
@@ -10338,6 +10340,19 @@ virDomainVideoDefParseXML(xmlNodePtr node,
         def->vram = virDomainVideoDefaultRAM(dom, def->type);
     }
 
+    if (vgamem) {
+        if (def->type != VIR_DOMAIN_VIDEO_TYPE_QXL) {
+            virReportError(VIR_ERR_XML_ERROR, "%s",
+                           _("vgamem attribute only supported for type of qxl"));
+            goto error;
+        }
+        if (virStrToLong_ui(vgamem, NULL, 10, &def->vgamem) < 0) {
+            virReportError(VIR_ERR_XML_ERROR,
+                           _("cannot parse video vgamem '%s'"), vgamem);
+            goto error;
+        }
+    }
+
     if (heads) {
         if (virStrToLong_ui(heads, NULL, 10, &def->heads) < 0) {
             virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -10354,6 +10369,7 @@ virDomainVideoDefParseXML(xmlNodePtr node,
     VIR_FREE(type);
     VIR_FREE(ram);
     VIR_FREE(vram);
+    VIR_FREE(vgamem);
     VIR_FREE(heads);
 
     return def;
@@ -10363,6 +10379,7 @@ virDomainVideoDefParseXML(xmlNodePtr node,
     VIR_FREE(type);
     VIR_FREE(ram);
     VIR_FREE(vram);
+    VIR_FREE(vgamem);
     VIR_FREE(heads);
     return NULL;
 }
@@ -14739,6 +14756,13 @@ virDomainVideoDefCheckABIStability(virDomainVideoDefPtr src,
         return false;
     }
 
+    if (src->vgamem != dst->vgamem) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("Target video card vgamem %u does not match source %u"),
+                       dst->vgamem, src->vgamem);
+        return false;
+    }
+
     if (src->heads != dst->heads) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("Target video card heads %u does not match source %u"),
@@ -18119,6 +18143,8 @@ virDomainVideoDefFormat(virBufferPtr buf,
         virBufferAsprintf(buf, " ram='%u'", def->ram);
     if (def->vram)
         virBufferAsprintf(buf, " vram='%u'", def->vram);
+    if (def->vgamem)
+        virBufferAsprintf(buf, " vgamem='%u'", def->vgamem);
     if (def->heads)
         virBufferAsprintf(buf, " heads='%u'", def->heads);
     if (def->primary)

src/conf/domain_conf.h

@@ -1293,6 +1293,7 @@ struct _virDomainVideoDef {
     int type;
     unsigned int ram;  /* kibibytes (multiples of 1024) */
     unsigned int vram; /* kibibytes (multiples of 1024) */
+    unsigned int vgamem; /* kibibytes (multiples of 1024) */
     unsigned int heads;
     bool primary;
     virDomainVideoAccelDefPtr accel;

src/qemu/qemu_command.c

@@ -4911,6 +4911,12 @@ qemuBuildDeviceVideoStr(virDomainDefPtr def,
             /* QEMU accepts bytes for vram_size. */
             virBufferAsprintf(&buf, ",vram_size=%u", video->vram * 1024);
         }
+
+        if ((primary && virQEMUCapsGet(qemuCaps, QEMU_CAPS_QXL_VGA_VGAMEM)) ||
+            (!primary && virQEMUCapsGet(qemuCaps, QEMU_CAPS_QXL_VGAMEM))) {
+            /* QEMU accepts mebibytes for vgamem_mb. */
+            virBufferAsprintf(&buf, ",vgamem_mb=%u", video->vgamem / 1024);
+        }
     } else if (video->vram &&
         ((video->type == VIR_DOMAIN_VIDEO_TYPE_VGA &&
           virQEMUCapsGet(qemuCaps, QEMU_CAPS_VGA_VGAMEM)) ||
@@ -9244,6 +9250,7 @@ qemuBuildCommandLine(virConnectPtr conn,
                     virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE)) {
                     unsigned int ram = def->videos[0]->ram;
                     unsigned int vram = def->videos[0]->vram;
+                    unsigned int vgamem = def->videos[0]->vgamem;
 
                     if (vram > (UINT_MAX / 1024)) {
                         virReportError(VIR_ERR_OVERFLOW,
@@ -9268,6 +9275,12 @@ qemuBuildCommandLine(virConnectPtr conn,
                         virCommandAddArgFormat(cmd, "%s.vram_size=%u",
                                                dev, vram * 1024);
                     }
+                    if (vgamem &&
+                        virQEMUCapsGet(qemuCaps, QEMU_CAPS_QXL_VGA_VGAMEM)) {
+                        virCommandAddArg(cmd, "-global");
+                        virCommandAddArgFormat(cmd, "%s.vgamem_mb=%u",
+                                               dev, vgamem / 1024);
+                    }
                 }
 
                 if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE) &&
@@ -12284,8 +12297,13 @@ qemuParseCommandLine(virCapsPtr qemuCaps,
         else
             vid->type = video;
         vid->vram = virDomainVideoDefaultRAM(def, vid->type);
-        vid->ram = vid->type == VIR_DOMAIN_VIDEO_TYPE_QXL ?
+        if (vid->type == VIR_DOMAIN_VIDEO_TYPE_QXL) {
-                       virDomainVideoDefaultRAM(def, vid->type) : 0;
+            vid->ram = virDomainVideoDefaultRAM(def, vid->type);
+            vid->vgamem = 8 * 1024;
+        } else {
+            vid->ram = 0;
+            vid->vgamem = 0;
+        }
         vid->heads = 1;
 
         if (VIR_APPEND_ELEMENT(def->videos, def->nvideos, vid) < 0) {

src/qemu/qemu_domain.c

@@ -1176,6 +1176,25 @@ qemuDomainDeviceDefPostParse(virDomainDeviceDefPtr dev,
         goto cleanup;
     }
 
+    if (dev->type == VIR_DOMAIN_DEVICE_VIDEO &&
+        dev->data.video->type == VIR_DOMAIN_VIDEO_TYPE_QXL) {
+        if (dev->data.video->vgamem) {
+            if (dev->data.video->vgamem < 1024) {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                               _("value for 'vgamem' must be at least 1 MiB "
+                                 "(1024 KiB)"));
+                goto cleanup;
+            }
+            if (dev->data.video->vgamem != VIR_ROUND_UP_POWER_OF_TWO(dev->data.video->vgamem)) {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                               _("value for 'vgamem' must be power of two"));
+                goto cleanup;
+            }
+        } else {
+            dev->data.video->vgamem = 8 * 1024;
+        }
+    }
+
     ret = 0;
 
  cleanup:

tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-compression.xml

@@ -33,10 +33,10 @@
       <streaming mode='filter'/>
     </graphics>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='virtio'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-qxl-vga.xml

@@ -30,10 +30,10 @@
       <channel name='inputs' mode='insecure'/>
     </graphics>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <video>
-      <model type='qxl' ram='65536' vram='65536' heads='1'/>
+      <model type='qxl' ram='65536' vram='65536' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='virtio'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-graphics-spice.xml

@@ -37,10 +37,10 @@
       <filetransfer enable='no'/>
     </graphics>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='virtio'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-pcihole64-q35.xml

@@ -26,7 +26,7 @@
     <controller type='pci' index='2' model='pci-bridge'/>
     <controller type='sata' index='0'/>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='none'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-q35.xml

@@ -23,7 +23,7 @@
     <controller type='pci' index='1' model='dmi-to-pci-bridge'/>
     <controller type='pci' index='2' model='pci-bridge'/>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='none'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-serial-spiceport.xml

@@ -37,7 +37,7 @@
       <listen type='address' address='127.0.0.1'/>
     </graphics>
     <video>
-      <model type='qxl' ram='65536' vram='65536' heads='1'/>
+      <model type='qxl' ram='65536' vram='65536' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='virtio'/>
   </devices>

tests/qemuxml2argvdata/qemuxml2argv-video-qxl-device-vgamem.args

@@ -2,5 +2,5 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 1024 -smp 1 -nographic -nodefaults \
 -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -hda /var/lib/libvirt/images/QEMUGuest1 \
--device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,bus=pci.0\
+-device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vgamem_mb=8\
-,addr=0x2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
+,bus=pci.0,addr=0x2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

tests/qemuxml2argvdata/qemuxml2argv-video-qxl-sec-device-vgamem.args

@@ -2,7 +2,7 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 1024 -smp 1 -nographic -nodefaults \
 -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -hda /var/lib/libvirt/images/QEMUGuest1 \
--device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,bus=pci.0\
+-device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vgamem_mb=8\
-,addr=0x2 -device qxl,id=video1,ram_size=67108864,vram_size=67108864,bus=pci.0\
+,bus=pci.0,addr=0x2 -device qxl,id=video1,ram_size=67108864,vram_size=67108864\
-,addr=0x4 \
+,vgamem_mb=8,bus=pci.0,addr=0x4 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

tests/qemuxml2argvtest.c

@@ -1362,13 +1362,15 @@ mymain(void)
     DO_TEST("video-qxl-device", QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_QXL_VGA,
             QEMU_CAPS_DEVICE_VIDEO_PRIMARY);
     DO_TEST("video-qxl-device-vgamem", QEMU_CAPS_DEVICE,
-            QEMU_CAPS_DEVICE_QXL_VGA, QEMU_CAPS_DEVICE_VIDEO_PRIMARY);
+            QEMU_CAPS_DEVICE_QXL_VGA, QEMU_CAPS_DEVICE_VIDEO_PRIMARY,
+            QEMU_CAPS_QXL_VGA_VGAMEM);
     DO_TEST_FAILURE("video-qxl-sec-nodevice", QEMU_CAPS_VGA, QEMU_CAPS_VGA_QXL);
     DO_TEST("video-qxl-sec-device", QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_QXL_VGA,
             QEMU_CAPS_DEVICE_QXL, QEMU_CAPS_DEVICE_VIDEO_PRIMARY);
     DO_TEST("video-qxl-sec-device-vgamem", QEMU_CAPS_DEVICE,
             QEMU_CAPS_DEVICE_QXL_VGA, QEMU_CAPS_DEVICE_QXL,
-            QEMU_CAPS_DEVICE_VIDEO_PRIMARY);
+            QEMU_CAPS_DEVICE_VIDEO_PRIMARY, QEMU_CAPS_QXL_VGA_VGAMEM,
+            QEMU_CAPS_QXL_VGAMEM);
 
     DO_TEST("virtio-rng-default", QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_VIRTIO_RNG,
             QEMU_CAPS_OBJECT_RNG_RANDOM);

tests/qemuxml2xmloutdata/qemuxml2xmlout-q35.xml

@@ -24,7 +24,7 @@
     <controller type='pci' index='2' model='pci-bridge'/>
     <controller type='sata' index='0'/>
     <video>
-      <model type='qxl' ram='65536' vram='32768' heads='1'/>
+      <model type='qxl' ram='65536' vram='32768' vgamem='8192' heads='1'/>
     </video>
     <memballoon model='none'/>
   </devices>