qemu: capabilities: Introduce QEMU_CAPS_BLOCKDEV_BACKUP

Upcoming commit will enable full backup support (incremental part
requires blockdev-reopen, which won't happen in qemu for at least
another release).

Add a capability that the 'blockdev-backup' job is supported by qemu
capped, but limited to when qemu supports QEMU_CAPS_BLOCKDEV.

We can also use it in the expression to enable
QEMU_CAPS_INCREMENTAL_BACKUP since it's a pre-requisite too.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_capabilities.c

@@ -622,6 +622,7 @@ VIR_ENUM_IMPL(virQEMUCaps,
               /* 395 */
               "vnc-power-control",
               "audiodev",
+              "blockdev-backup",
     );
 
 
@@ -1557,6 +1558,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsQMPSchemaQueries[] = {
     { "netdev_add/arg-type/+vhost-vdpa", QEMU_CAPS_NETDEV_VHOST_VDPA },
     { "migrate-set-parameters/arg-type/block-bitmap-mapping/bitmaps/transform",
       QEMU_CAPS_MIGRATION_PARAM_BLOCK_BITMAP_MAPPING },
+    { "blockdev-backup", QEMU_CAPS_BLOCKDEV_BACKUP },
 };
 
 typedef struct _virQEMUCapsObjectTypeProps virQEMUCapsObjectTypeProps;
@@ -5168,7 +5170,10 @@ virQEMUCapsInitQMPVersionCaps(virQEMUCapsPtr qemuCaps)
 void
 virQEMUCapsInitProcessCapsInterlock(virQEMUCapsPtr qemuCaps)
 {
-    if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV) &&
+    if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV))
+        virQEMUCapsClear(qemuCaps, QEMU_CAPS_BLOCKDEV_BACKUP);
+
+    if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV_BACKUP) &&
         virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV_REOPEN) &&
         virQEMUCapsGet(qemuCaps, QEMU_CAPS_MIGRATION_PARAM_BLOCK_BITMAP_MAPPING))
         virQEMUCapsSet(qemuCaps, QEMU_CAPS_INCREMENTAL_BACKUP);

src/qemu/qemu_capabilities.h

@@ -602,6 +602,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
     /* 395 */
     QEMU_CAPS_VNC_POWER_CONTROL, /* -vnc power-control option */
     QEMU_CAPS_AUDIODEV, /* -audiodev instead of QEMU_AUDIO_DRV */
+    QEMU_CAPS_BLOCKDEV_BACKUP, /* qemu supports the blockdev-backup job */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

tests/qemucapabilitiesdata/caps_4.2.0.aarch64.xml

@@ -198,6 +198,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>4001050</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>61700242</microcodeVersion>

tests/qemucapabilitiesdata/caps_4.2.0.s390x.xml

@@ -160,6 +160,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>4002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>39100242</microcodeVersion>

tests/qemucapabilitiesdata/caps_4.2.0.x86_64.xml

@@ -246,6 +246,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>4002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100242</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.0.0.aarch64.xml

@@ -208,6 +208,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5000000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>61700241</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.0.0.ppc64.xml

@@ -217,6 +217,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5000000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>42900241</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.0.0.riscv64.xml

@@ -203,6 +203,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5000000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>0</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.0.0.x86_64.xml

@@ -253,6 +253,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5000000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100241</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.1.0.sparc.xml

@@ -118,6 +118,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5001000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>0</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.1.0.x86_64.xml

@@ -255,6 +255,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5001000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100242</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.2.0.aarch64.xml

@@ -212,6 +212,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>61700243</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.2.0.ppc64.xml

@@ -219,6 +219,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>42900243</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.2.0.riscv64.xml

@@ -205,6 +205,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>0</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.2.0.s390x.xml

@@ -167,6 +167,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>39100243</microcodeVersion>

tests/qemucapabilitiesdata/caps_5.2.0.x86_64.xml

@@ -256,6 +256,7 @@
   <flag name='memory-backend-file.x-use-canonical-path-for-ramblock-id'/>
   <flag name='vnc-opts'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002000</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100243</microcodeVersion>

tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml

@@ -259,6 +259,7 @@
   <flag name='migration-param.block-bitmap-mapping'/>
   <flag name='vnc-power-control'/>
   <flag name='audiodev'/>
+  <flag name='blockdev-backup'/>
   <version>5002050</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100242</microcodeVersion>