From d0dc4217142fda8ce8850a30b7d89a344bb55d5e Mon Sep 17 00:00:00 2001

Message-Id: <d0dc4217142fda8ce8850a30b7d89a344bb55d5e@dist-git>

From: Peter Krempa <pkrempa@redhat.com>

Date: Tue, 23 Jun 2020 12:23:35 +0200

Subject: [PATCH] qemu: backup: Split up code traversing checkpoint list

 looking for bitmaps

MIME-Version: 1.0

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The algorithm is getting quite complex. Split out the lookup of range of

backing chain storage sources and bitmaps contained in them which

correspond to one checkpoint.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>

Reviewed-by: Eric Blake <eblake@redhat.com>

(cherry picked from commit 562511afa6cef5948e6339596ba5954cb5ed0565)

https://bugzilla.redhat.com/show_bug.cgi?id=1804593

Message-Id: <b3a1485033a5bb425f261caeb299973b2f39bbff.1592906423.git.pkrempa@redhat.com>

Reviewed-by: Ján Tomko <jtomko@redhat.com>

---

 src/qemu/qemu_backup.c | 111 ++++++++++++++++++++++-------------------

 1 file changed, 61 insertions(+), 50 deletions(-)

diff --git a/src/qemu/qemu_backup.c b/src/qemu/qemu_backup.c

index 5d18720f53..400b711f79 100644

--- a/src/qemu/qemu_backup.c

+++ b/src/qemu/qemu_backup.c

@@ -173,72 +173,83 @@ qemuBackupDiskDataCleanup(virDomainObjPtr vm,

 }

+static int

+qemuBackupGetBitmapMergeRange(virStorageSourcePtr from,

+                              const char *bitmapname,

+                              virJSONValuePtr *actions,

+                              virStorageSourcePtr *to,

+                              const char *diskdst,

+                              virHashTablePtr blockNamedNodeData)

+{

+    g_autoptr(virJSONValue) act = virJSONValueNewArray();

+    virStorageSourcePtr tmpsrc = NULL;

+    virStorageSourcePtr n;

+    bool foundbitmap = false;

+

+    for (n = from; virStorageSourceIsBacking(n); n = n->backingStore) {

+        qemuBlockNamedNodeDataBitmapPtr bitmap = NULL;

+

+        if (!(bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData,

+                                                             n,

+                                                             bitmapname)))

+            break;

+

+        foundbitmap = true;

+

+        if (bitmap->inconsistent) {

+            virReportError(VIR_ERR_INVALID_ARG,

+                           _("bitmap '%s' for image '%s%u' is inconsistent"),

+                           bitmap->name, diskdst, n->id);

+            return -1;

+        }

+

+        if (qemuMonitorTransactionBitmapMergeSourceAddBitmap(act,

+                                                             n->nodeformat,

+                                                             bitmapname) < 0)

+            return -1;

+

+        tmpsrc = n;

+    }

+

+    if (!foundbitmap) {

+        virReportError(VIR_ERR_INVALID_ARG,

+                       _("failed to find bitmap '%s' in image '%s%u'"),

+                       bitmapname, diskdst, from->id);

+        return -1;

+    }

+

+    *actions = g_steal_pointer(&act;;

+    *to = tmpsrc;

+

+    return 0;

+}

+

+

 virJSONValuePtr

 qemuBackupDiskPrepareOneBitmapsChain(virDomainMomentDefPtr *incremental,

                                      virStorageSourcePtr backingChain,

                                      virHashTablePtr blockNamedNodeData,

                                      const char *diskdst)

 {

-    qemuBlockNamedNodeDataBitmapPtr bitmap;

     g_autoptr(virJSONValue) ret = NULL;

     size_t incridx = 0;

+    virStorageSourcePtr n = backingChain;

     ret = virJSONValueNewArray();

-    if (!(bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData,

-                                                         backingChain,

-                                                         incremental[0]->name))) {

-        virReportError(VIR_ERR_INVALID_ARG,

-                       _("failed to find bitmap '%s' in image '%s%u'"),

-                       incremental[0]->name, diskdst, backingChain->id);

-        return NULL;

-    }

+    for (incridx = 0; incremental[incridx]; incridx++) {

+        g_autoptr(virJSONValue) tmp = virJSONValueNewArray();

+        virStorageSourcePtr tmpsrc = NULL;

-    while (bitmap) {

-        if (bitmap->inconsistent) {

-            virReportError(VIR_ERR_INVALID_ARG,

-                           _("bitmap '%s' for image '%s%u' is inconsistent"),

-                           bitmap->name, diskdst, backingChain->id);

+        if (qemuBackupGetBitmapMergeRange(n, incremental[incridx]->name,

+                                          &tmp, &tmpsrc, diskdst,

+                                          blockNamedNodeData) < 0)

             return NULL;

-        }

-        if (qemuMonitorTransactionBitmapMergeSourceAddBitmap(ret,

-                                                             backingChain->nodeformat,

-                                                             bitmap->name) < 0)

+        if (virJSONValueArrayConcat(ret, tmp) < 0)

             return NULL;

-        if (backingChain->backingStore &&

-            (bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData,

-                                                            backingChain->backingStore,

-                                                            incremental[incridx]->name))) {

-            backingChain = backingChain->backingStore;

-            continue;

-        }

-

-        if (incremental[incridx + 1]) {

-            if ((bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData,

-                                                                backingChain,

-                                                                incremental[incridx + 1]->name))) {

-                incridx++;

-                continue;

-            }

-

-            if (backingChain->backingStore &&

-                (bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData,

-                                                                backingChain->backingStore,

-                                                                incremental[incridx + 1]->name))) {

-                incridx++;

-                backingChain = backingChain->backingStore;

-                continue;

-            }

-

-            virReportError(VIR_ERR_INVALID_ARG,

-                           _("failed to find bitmap '%s' in image '%s%u'"),

-                           incremental[incridx]->name, diskdst, backingChain->id);

-            return NULL;

-        } else {

-            break;

-        }

+        n = tmpsrc;

     }

     return g_steal_pointer(&ret;;

-- 

2.27.0