qemuDomainBlockCommit: Handle bitmaps on start of commit

On start of the commit job, we need to disable any active bitmap in the
base. Use qemuBlockBitmapsHandleCommitStart to calculate which and call
the appropriate QMP APIs. We use blockdev-reopen to make the 'base'
writable to disable the bitmaps.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 2799094fe6a8a307573081b8bb0489a52b6ea730..3d5633f1e9ca9856d1e4c67029dac975881135df 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -18399,6 +18399,8 @@ qemuDomainBlockCommit(virDomainPtr dom,
     const char *nodebase = NULL;
     bool persistjob = false;
     bool blockdev = false;
+    g_autoptr(virJSONValue) bitmapDisableActions = NULL;
+    VIR_AUTOSTRINGLIST bitmapDisableList = NULL;
 
     virCheckFlags(VIR_DOMAIN_BLOCK_COMMIT_SHALLOW |
                   VIR_DOMAIN_BLOCK_COMMIT_ACTIVE |
@@ -18555,8 +18557,29 @@ qemuDomainBlockCommit(virDomainPtr dom,
             goto endjob;
     }
 
+    if (blockdev &&
+        virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV_REOPEN)) {
+        g_autoptr(virHashTable) blockNamedNodeData = NULL;
+        if (!(blockNamedNodeData = qemuBlockGetNamedNodeData(vm, QEMU_ASYNC_JOB_NONE)))
+            goto endjob;
+
+        if (qemuBlockBitmapsHandleCommitStart(topSource, baseSource,
+                                              blockNamedNodeData,
+                                              &bitmapDisableActions,
+                                              &bitmapDisableList) < 0)
+            goto endjob;
+
+        /* if we don't have terminator on 'base' we can't reopen it */
+        if (bitmapDisableActions && !baseSource->backingStore) {
+            virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
+                           _("can't handle bitmaps on unterminated backing image '%s'"),
+                           base);
+            goto endjob;
+        }
+    }
+
     if (!(job = qemuBlockJobDiskNewCommit(vm, disk, top_parent, topSource,
-                                          baseSource, NULL,
+                                          baseSource, &bitmapDisableList,
                                           flags & VIR_DOMAIN_BLOCK_COMMIT_DELETE,
                                           flags)))
         goto endjob;
@@ -18578,6 +18601,24 @@ qemuDomainBlockCommit(virDomainPtr dom,
         if (!backingPath && top_parent &&
             !(backingPath = qemuBlockGetBackingStoreString(baseSource)))
             goto endjob;
+
+        if (bitmapDisableActions) {
+            int rc;
+
+            if (qemuBlockReopenReadWrite(vm, baseSource, QEMU_ASYNC_JOB_NONE) < 0)
+                goto endjob;
+
+            qemuDomainObjEnterMonitor(driver, vm);
+            rc = qemuMonitorTransaction(priv->mon, &bitmapDisableActions);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto endjob;
+
+            if (qemuBlockReopenReadOnly(vm, baseSource, QEMU_ASYNC_JOB_NONE) < 0)
+                goto endjob;
+
+            if (rc < 0)
+                goto endjob;
+        }
     } else {
         device = job->name;
     }