In cases where we are copying the storage we need to ensure that also
bitmaps are copied properly. This patch adds migration cookie XML
infrastructure which will allow the migration sides reach consensus on
which bitmaps to migrate.

Signed-off-by: Peter Krempa <pkre...@redhat.com>
---
 src/qemu/qemu_migration_cookie.c | 134 +++++++++++++++++++++++++++++++
 src/qemu/qemu_migration_cookie.h |  34 ++++++++
 2 files changed, 168 insertions(+)

diff --git a/src/qemu/qemu_migration_cookie.c b/src/qemu/qemu_migration_cookie.c
index 6f2b1b2f57..94ba9c83d0 100644
--- a/src/qemu/qemu_migration_cookie.c
+++ b/src/qemu/qemu_migration_cookie.c
@@ -51,6 +51,7 @@ VIR_ENUM_IMPL(qemuMigrationCookieFlag,
               "cpu",
               "allowReboot",
               "capabilities",
+              "block-dirty-bitmaps",
 );


@@ -116,6 +117,39 @@ qemuMigrationCookieCapsFree(qemuMigrationCookieCapsPtr 
caps)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(qemuMigrationCookieCaps,
                               qemuMigrationCookieCapsFree);

+static void
+qemuMigrationBlockDirtyBitmapsDiskBitmapFree(qemuMigrationBlockDirtyBitmapsDiskBitmapPtr
 bmp)
+{
+    if (!bmp)
+        return;
+
+    g_free(bmp->bitmapname);
+    g_free(bmp->alias);
+    g_free(bmp->sourcebitmap);
+    g_free(bmp);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(qemuMigrationBlockDirtyBitmapsDiskBitmap,
+                              qemuMigrationBlockDirtyBitmapsDiskBitmapFree);
+
+
+static void
+qemuMigrationBlockDirtyBitmapsDiskFree(qemuMigrationBlockDirtyBitmapsDiskPtr 
dsk)
+{
+    if (!dsk)
+        return;
+
+    g_free(dsk->target);
+    if (dsk->bitmaps)
+        g_slist_free_full(dsk->bitmaps,
+                          (GDestroyNotify) 
qemuMigrationBlockDirtyBitmapsDiskBitmapFree);
+    g_free(dsk);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(qemuMigrationBlockDirtyBitmapsDisk,
+                              qemuMigrationBlockDirtyBitmapsDiskFree);
+
+
 void
 qemuMigrationCookieFree(qemuMigrationCookiePtr mig)
 {
@@ -135,6 +169,9 @@ qemuMigrationCookieFree(qemuMigrationCookiePtr mig)
     g_clear_pointer(&mig->jobInfo, qemuDomainJobInfoFree);
     virCPUDefFree(mig->cpu);
     qemuMigrationCookieCapsFree(mig->caps);
+    if (mig->blockDirtyBitmaps)
+        g_slist_free_full(mig->blockDirtyBitmaps,
+                          (GDestroyNotify) 
qemuMigrationBlockDirtyBitmapsDiskFree);
     g_free(mig);
 }

@@ -758,6 +795,48 @@ qemuMigrationCookieNBDXMLFormat(qemuMigrationCookieNBDPtr 
nbd,
 }


+static void
+qemuMigrationCookieBlockDirtyBitmapsFormat(virBufferPtr buf,
+                                           GSList *bitmaps)
+{
+    g_auto(virBuffer) disksBuf = VIR_BUFFER_INIT_CHILD(buf);
+    GSList *nextdisk;
+
+    for (nextdisk = bitmaps; nextdisk; nextdisk = nextdisk->next) {
+        qemuMigrationBlockDirtyBitmapsDiskPtr disk = nextdisk->data;
+        g_auto(virBuffer) diskAttrBuf = VIR_BUFFER_INITIALIZER;
+        g_auto(virBuffer) diskChildBuf = VIR_BUFFER_INIT_CHILD(&disksBuf);
+        bool hasBitmaps = false;
+        GSList *nextbitmap;
+
+        if (disk->skip || !disk->bitmaps)
+            continue;
+
+        for (nextbitmap = disk->bitmaps; nextbitmap; nextbitmap = 
nextbitmap->next) {
+            qemuMigrationBlockDirtyBitmapsDiskBitmapPtr bitmap = 
nextbitmap->data;
+
+            if (bitmap->skip)
+                continue;
+
+            virBufferAsprintf(&diskChildBuf,
+                              "<bitmap name='%s' alias='%s'/>\n",
+                              bitmap->bitmapname, bitmap->alias);
+
+            hasBitmaps = true;
+        }
+
+        if (!hasBitmaps)
+            continue;
+
+        virBufferAsprintf(&diskAttrBuf, " target='%s'", disk->target);
+        virXMLFormatElement(&disksBuf, "disk", &diskAttrBuf, &diskChildBuf);
+    }
+
+
+    virXMLFormatElement(buf, "blockDirtyBitmaps", NULL, &disksBuf);
+}
+
+
 int
 qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,
                              virQEMUCapsPtr qemuCaps,
@@ -829,6 +908,9 @@ qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,
     if (mig->flags & QEMU_MIGRATION_COOKIE_CAPS)
         qemuMigrationCookieCapsXMLFormat(buf, mig->caps);

+    if (mig->flags & QEMU_MIGRATION_COOKIE_BLOCK_DIRTY_BITMAPS)
+        qemuMigrationCookieBlockDirtyBitmapsFormat(buf, 
mig->blockDirtyBitmaps);
+
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</qemu-migration>\n");
     return 0;
@@ -1132,6 +1214,53 @@ 
qemuMigrationCookieXMLParseMandatoryFeatures(xmlXPathContextPtr ctxt,
 }


+static int
+qemuMigrationCookieBlockDirtyBitmapsParse(xmlXPathContextPtr ctxt,
+                                          qemuMigrationCookiePtr mig)
+{
+    g_autoslist(qemuMigrationBlockDirtyBitmapsDisk) disks = NULL;
+    g_autofree xmlNodePtr *disknodes = NULL;
+    int ndisknodes;
+    size_t i;
+    VIR_XPATH_NODE_AUTORESTORE(ctxt)
+
+    if ((ndisknodes = virXPathNodeSet("./blockDirtyBitmaps/disk", ctxt, 
&disknodes)) < 0)
+        return -1;
+
+    for (i = 0; i < ndisknodes; i++) {
+        GSList *bitmaps = NULL;
+        qemuMigrationBlockDirtyBitmapsDiskPtr disk;
+        g_autofree xmlNodePtr *bitmapnodes = NULL;
+        int nbitmapnodes;
+        size_t j;
+
+        ctxt->node = disknodes[i];
+
+        if ((nbitmapnodes = virXPathNodeSet("./bitmap", ctxt, &bitmapnodes)) < 
0)
+            return -1;
+
+        for (j = 0; j < nbitmapnodes; j++) {
+            qemuMigrationBlockDirtyBitmapsDiskBitmapPtr bitmap;
+
+            bitmap = g_new0(qemuMigrationBlockDirtyBitmapsDiskBitmap, 1);
+            bitmap->bitmapname = virXMLPropString(bitmapnodes[j], "name");
+            bitmap->alias = virXMLPropString(bitmapnodes[j], "alias");
+            bitmaps = g_slist_prepend(bitmaps, bitmap);
+        }
+
+        disk = g_new0(qemuMigrationBlockDirtyBitmapsDisk, 1);
+        disk->target = virXMLPropString(disknodes[i], "target");
+        disk->bitmaps = g_slist_reverse(bitmaps);
+
+        disks = g_slist_prepend(disks, disk);
+    }
+
+    mig->blockDirtyBitmaps = g_slist_reverse(g_steal_pointer(&disks));
+
+    return 0;
+}
+
+
 static int
 qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig,
                             virQEMUDriverPtr driver,
@@ -1275,6 +1404,11 @@ qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig,
         !(mig->caps = qemuMigrationCookieCapsXMLParse(ctxt)))
         return -1;

+    if (flags & QEMU_MIGRATION_COOKIE_BLOCK_DIRTY_BITMAPS &&
+        virXPathBoolean("boolean(./blockDirtyBitmaps)", ctxt) &&
+        qemuMigrationCookieBlockDirtyBitmapsParse(ctxt, mig) < 0)
+        return -1;
+
     return 0;
 }

diff --git a/src/qemu/qemu_migration_cookie.h b/src/qemu/qemu_migration_cookie.h
index ecd1a01375..8636f955da 100644
--- a/src/qemu/qemu_migration_cookie.h
+++ b/src/qemu/qemu_migration_cookie.h
@@ -35,6 +35,7 @@ typedef enum {
     QEMU_MIGRATION_COOKIE_FLAG_CPU,
     QEMU_MIGRATION_COOKIE_FLAG_ALLOW_REBOOT,
     QEMU_MIGRATION_COOKIE_FLAG_CAPS,
+    QEMU_MIGRATION_COOKIE_FLAG_BLOCK_DIRTY_BITMAPS,

     QEMU_MIGRATION_COOKIE_FLAG_LAST
 } qemuMigrationCookieFlags;
@@ -53,6 +54,7 @@ typedef enum {
     QEMU_MIGRATION_COOKIE_CPU = (1 << QEMU_MIGRATION_COOKIE_FLAG_CPU),
     QEMU_MIGRATION_COOKIE_ALLOW_REBOOT = (1 << 
QEMU_MIGRATION_COOKIE_FLAG_ALLOW_REBOOT),
     QEMU_MIGRATION_COOKIE_CAPS = (1 << QEMU_MIGRATION_COOKIE_FLAG_CAPS),
+    QEMU_MIGRATION_COOKIE_BLOCK_DIRTY_BITMAPS = (1 << 
QEMU_MIGRATION_COOKIE_FLAG_BLOCK_DIRTY_BITMAPS),
 } qemuMigrationCookieFeatures;

 typedef struct _qemuMigrationCookieGraphics qemuMigrationCookieGraphics;
@@ -107,6 +109,35 @@ struct _qemuMigrationCookieCaps {
     virBitmapPtr automatic;
 };

+typedef struct _qemuMigrationBlockDirtyBitmapsDiskBitmap 
qemuMigrationBlockDirtyBitmapsDiskBitmap;
+typedef qemuMigrationBlockDirtyBitmapsDiskBitmap 
*qemuMigrationBlockDirtyBitmapsDiskBitmapPtr;
+struct _qemuMigrationBlockDirtyBitmapsDiskBitmap {
+    /* config */
+    char *bitmapname;
+    char *alias;
+
+    /* runtime */
+    virTristateBool persistent; /* force persisting of the bitmap */
+    char *sourcebitmap; /* optional, actual bitmap to migrate in case we needed
+                           to create a temporary one by merging */
+    bool skip; /* omit this bitmap */
+};
+
+
+typedef struct _qemuMigrationBlockDirtyBitmapsDisk 
qemuMigrationBlockDirtyBitmapsDisk;
+typedef qemuMigrationBlockDirtyBitmapsDisk 
*qemuMigrationBlockDirtyBitmapsDiskPtr;
+struct _qemuMigrationBlockDirtyBitmapsDisk {
+    char *target;
+
+    GSList *bitmaps;
+
+    /* runtime data */
+    virDomainDiskDefPtr disk; /* disk object corresponding to 'target' */
+    const char *nodename; /* nodename of the top level source of 'disk' */
+    bool skip; /* omit this disk */
+};
+
+
 typedef struct _qemuMigrationCookie qemuMigrationCookie;
 typedef qemuMigrationCookie *qemuMigrationCookiePtr;
 struct _qemuMigrationCookie {
@@ -150,6 +181,9 @@ struct _qemuMigrationCookie {

     /* If flags & QEMU_MIGRATION_COOKIE_CAPS */
     qemuMigrationCookieCapsPtr caps;
+
+    /* If flags & QEMU_MIGRATION_COOKIE_BLOCK_DIRTY_BITMAPS */
+    GSList *blockDirtyBitmaps;
 };


-- 
2.29.2

Reply via email to