vz: implement p2p migration

Peer to peer migration is implemented just as in managed case. Basically
it is copy paste from managed case but with all the branches that are not
applied to vz removed.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

src/vz/vz_driver.c

@@ -2218,7 +2218,8 @@ vzEatCookie(const char *cookiein, int cookieinlen)
     goto cleanup;
 }
 
-#define VZ_MIGRATION_FLAGS      VIR_MIGRATE_PAUSED
+#define VZ_MIGRATION_FLAGS         (VIR_MIGRATE_PAUSED |        \
+                                    VIR_MIGRATE_PEER2PEER)
 
 #define VZ_MIGRATION_PARAMETERS                                 \
     VIR_MIGRATE_PARAM_DEST_XML,         VIR_TYPED_PARAM_STRING, \
@@ -2376,6 +2377,7 @@ vzConnectSupportsFeature(virConnectPtr conn ATTRIBUTE_UNUSED, int feature)
 {
     switch (feature) {
     case VIR_DRV_FEATURE_MIGRATION_PARAMS:
+    case VIR_DRV_FEATURE_MIGRATION_P2P:
         return 1;
     default:
         return 0;
@@ -2419,14 +2421,11 @@ vzParseVzURI(const char *uri_str)
 }
 
 static int
-vzDomainMigratePerform3Params(virDomainPtr domain,
-                              const char *dconnuri ATTRIBUTE_UNUSED,
+vzDomainMigratePerformStep(virDomainPtr domain,
                            virTypedParameterPtr params,
                            int nparams,
                            const char *cookiein,
                            int cookieinlen,
-                              char **cookieout ATTRIBUTE_UNUSED,
-                              int *cookieoutlen ATTRIBUTE_UNUSED,
                            unsigned int flags)
 {
     int ret = -1;
@@ -2480,6 +2479,123 @@ vzDomainMigratePerform3Params(virDomainPtr domain,
     return ret;
 }
 
+static int
+vzDomainMigratePerformP2P(virDomainPtr domain,
+                          const char *dconnuri,
+                          virTypedParameterPtr orig_params,
+                          int nparams,
+                          unsigned int flags)
+{
+    virDomainPtr ddomain = NULL;
+    char *uri = NULL;
+    char *cookiein = NULL;
+    char *cookieout = NULL;
+    char *dom_xml = NULL;
+    int cookieinlen = 0;
+    int cookieoutlen = 0;
+    virErrorPtr orig_err = NULL;
+    int cancelled = 1;
+    virConnectPtr dconn = NULL;
+    virTypedParameterPtr params = NULL;
+    int ret = -1;
+
+    if (virTypedParamsCopy(&params, orig_params, nparams) < 0)
+        return -1;
+
+    if (!(dconn = virConnectOpen(dconnuri)))
+        goto done;
+
+    if (!(dom_xml = vzDomainMigrateBegin3Params(domain, params, nparams,
+                                                &cookieout, &cookieoutlen,
+                                                flags)))
+        goto done;
+
+    cookiein = cookieout;
+    cookieinlen = cookieoutlen;
+    cookieout = NULL;
+    cookieoutlen = 0;
+    if (dconn->driver->domainMigratePrepare3Params
+            (dconn, params, nparams, cookiein, cookieinlen,
+             &cookieout, &cookieoutlen, &uri, flags) < 0)
+        goto done;
+
+    /* preparation step was successful, thus on any error we must perform
+     * finish step to finalize migration on target
+     */
+    if (uri && virTypedParamsReplaceString(&params, &nparams,
+                                           VIR_MIGRATE_PARAM_URI, uri) < 0) {
+        orig_err = virSaveLastError();
+        goto finish;
+    }
+
+    VIR_FREE(cookiein);
+    cookiein = cookieout;
+    cookieinlen = cookieoutlen;
+    cookieout = NULL;
+    cookieoutlen = 0;
+    if (vzDomainMigratePerformStep(domain, params, nparams, cookiein,
+                                   cookieinlen, flags) < 0) {
+        orig_err = virSaveLastError();
+        goto finish;
+    }
+
+    cancelled = 0;
+
+ finish:
+    if (virTypedParamsGetString(params, nparams,
+                                VIR_MIGRATE_PARAM_DEST_NAME, NULL) <= 0 &&
+        virTypedParamsReplaceString(&params, &nparams,
+                                    VIR_MIGRATE_PARAM_DEST_NAME,
+                                    domain->name) < 0)
+        goto done;
+
+    ddomain = dconn->driver->domainMigrateFinish3Params(dconn, params, nparams,
+                                                        NULL, 0, NULL, NULL,
+                                                        flags, cancelled);
+    if (ddomain)
+        ret = 0;
+    virObjectUnref(ddomain);
+
+    /* confirm step is NOOP thus no need to call it */
+
+ done:
+    if (orig_err) {
+        virSetError(orig_err);
+        virFreeError(orig_err);
+    }
+    VIR_FREE(dom_xml);
+    VIR_FREE(uri);
+    VIR_FREE(cookiein);
+    VIR_FREE(cookieout);
+    virTypedParamsFree(params, nparams);
+    virObjectUnref(dconn);
+    return ret;
+}
+
+static int
+vzDomainMigratePerform3Params(virDomainPtr domain,
+                              const char *dconnuri,
+                              virTypedParameterPtr params,
+                              int nparams,
+                              const char *cookiein,
+                              int cookieinlen,
+                              char **cookieout ATTRIBUTE_UNUSED,
+                              int *cookieoutlen ATTRIBUTE_UNUSED,
+                              unsigned int flags)
+{
+    virCheckFlags(VZ_MIGRATION_FLAGS, -1);
+
+    if (virTypedParamsValidate(params, nparams, VZ_MIGRATION_PARAMETERS) < 0)
+        return -1;
+
+    if (flags & VIR_MIGRATE_PEER2PEER)
+        return vzDomainMigratePerformP2P(domain, dconnuri, params, nparams, flags);
+    else
+        return vzDomainMigratePerformStep(domain, params, nparams,
+                                          cookiein, cookieinlen, flags);
+
+}
+
 static virDomainPtr
 vzDomainMigrateFinish3Params(virConnectPtr dconn,
                              virTypedParameterPtr params,