Hi,
Migration will be disallowed when the vm uses host devices or has
snapshots (qemuMigrationIsAllowed)[1]. Would it make sense to introduce
a VIR_MIGRATE_FORCE similar to VIR_REVERT_FORCE here? We could then
introduce error codes similar to the snapshot case
(VIR_ERR_MIGRATE_RISKY).
This path is just to illustrate the idea not to be applied as is.
Cheers,
-- Guido
[1] Hopefully we can make migration with snapshots safe in the future by
transfering the metadata. A current hack around is to put this onto
shared storage and reread it on the destination side after migration.
>From 4628166c7cbb247da8726248c7e54b265da99a7d Mon Sep 17 00:00:00 2001
From: Guido Guenther <agx@xxxxxxxxxxx>
Date: Thu, 13 Oct 2011 12:05:08 +0200
Subject: [PATCH] Introduce VIR_MIGRATE_FORCE flag to allow for risky
migrations
Change errors indicating risky migration to VIR_ERR_MIGRATE_RISKY.
---
include/libvirt/libvirt.h.in | 3 ++-
include/libvirt/virterror.h | 2 ++
src/qemu/qemu_driver.c | 10 +++++-----
src/qemu/qemu_migration.c | 38 ++++++++++++++++++++++++--------------
src/qemu/qemu_migration.h | 13 +++++++++----
src/util/virterror.c | 6 ++++++
6 files changed, 48 insertions(+), 24 deletions(-)
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index 361881a..1f147f1 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -767,7 +767,8 @@ typedef enum {
VIR_MIGRATE_CHANGE_PROTECTION = (1 << 8), /* protect for changing domain configuration through the
* whole migration process; this will be used automatically
* when supported */
-
+ VIR_MIGRATE_FORCE = (1 << 9), /* Force migration even when we have host devices in use
+ or have snapshotes */
} virDomainMigrateFlags;
/* Domain migration. */
diff --git a/include/libvirt/virterror.h b/include/libvirt/virterror.h
index a8549b7..cc09ea0 100644
--- a/include/libvirt/virterror.h
+++ b/include/libvirt/virterror.h
@@ -240,6 +240,8 @@ typedef enum {
VIR_ERR_STORAGE_POOL_BUILT = 76, /* storage pool already built */
VIR_ERR_SNAPSHOT_REVERT_RISKY = 77, /* force was not requested for a
risky domain snapshot revert */
+ VIR_ERR_MIGRATE_RISKY = 78, /* force was not requested for a
+ risky domain migration */
} virErrorNumber;
/**
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 6b65716..5e5214d 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -7881,7 +7881,7 @@ qemudDomainMigratePrepareTunnel(virConnectPtr dconn,
ret = qemuMigrationPrepareTunnel(driver, dconn,
NULL, 0, NULL, NULL, /* No cookies in v2 */
- st, dname, dom_xml);
+ st, dname, dom_xml, flags);
cleanup:
qemuDriverUnlock(driver);
@@ -7941,7 +7941,7 @@ qemudDomainMigratePrepare2 (virConnectPtr dconn,
ret = qemuMigrationPrepareDirect(driver, dconn,
NULL, 0, NULL, NULL, /* No cookies */
uri_in, uri_out,
- dname, dom_xml);
+ dname, dom_xml, flags);
cleanup:
qemuDriverUnlock(driver);
@@ -8094,7 +8094,7 @@ qemuDomainMigrateBegin3(virDomainPtr domain,
goto endjob;
if (!(xml = qemuMigrationBegin(driver, vm, xmlin, dname,
- cookieout, cookieoutlen)))
+ cookieout, cookieoutlen, flags)))
goto endjob;
if ((flags & VIR_MIGRATE_CHANGE_PROTECTION)) {
@@ -8171,7 +8171,7 @@ qemuDomainMigratePrepare3(virConnectPtr dconn,
cookiein, cookieinlen,
cookieout, cookieoutlen,
uri_in, uri_out,
- dname, dom_xml);
+ dname, dom_xml, flags);
cleanup:
qemuDriverUnlock(driver);
@@ -8216,7 +8216,7 @@ qemuDomainMigratePrepareTunnel3(virConnectPtr dconn,
ret = qemuMigrationPrepareTunnel(driver, dconn,
cookiein, cookieinlen,
cookieout, cookieoutlen,
- st, dname, dom_xml);
+ st, dname, dom_xml, flags);
qemuDriverUnlock(driver);
cleanup:
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index decb0f2..3263c2f 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -788,18 +788,24 @@ error:
* the fact that older servers did not do checks on the source. */
static bool
qemuMigrationIsAllowed(struct qemud_driver *driver, virDomainObjPtr vm,
- virDomainDefPtr def)
+ virDomainDefPtr def, int flags)
{
int nsnapshots;
+ /* FIXME: there are different kinds of risk (a missing host device
+ might break the vm entirely while missing snapshots will not */
+ if (flags & VIR_MIGRATE_FORCE) {
+ return true;
+ }
+
if (vm) {
if (qemuProcessAutoDestroyActive(driver, vm)) {
- qemuReportError(VIR_ERR_OPERATION_INVALID,
+ qemuReportError(VIR_ERR_MIGRATE_RISKY,
"%s", _("domain is marked for auto destroy"));
return false;
}
if ((nsnapshots = virDomainSnapshotObjListNum(&vm->snapshots, 0))) {
- qemuReportError(VIR_ERR_OPERATION_INVALID,
+ qemuReportError(VIR_ERR_MIGRATE_RISKY,
_("cannot migrate domain with %d snapshots"),
nsnapshots);
return false;
@@ -808,7 +814,7 @@ qemuMigrationIsAllowed(struct qemud_driver *driver, virDomainObjPtr vm,
def = vm->def;
}
if (def->nhostdevs > 0) {
- qemuReportError(VIR_ERR_OPERATION_INVALID,
+ qemuReportError(VIR_ERR_MIGRATE_RISKY,
"%s", _("Domain with assigned host devices cannot be migrated"));
return false;
}
@@ -1002,7 +1008,8 @@ char *qemuMigrationBegin(struct qemud_driver *driver,
const char *xmlin,
const char *dname,
char **cookieout,
- int *cookieoutlen)
+ int *cookieoutlen,
+ unsigned long flags)
{
char *rv = NULL;
qemuMigrationCookiePtr mig = NULL;
@@ -1021,7 +1028,7 @@ char *qemuMigrationBegin(struct qemud_driver *driver,
if (priv->job.asyncJob == QEMU_ASYNC_JOB_MIGRATION_OUT)
qemuMigrationJobSetPhase(driver, vm, QEMU_MIGRATION_PHASE_BEGIN3);
- if (!qemuMigrationIsAllowed(driver, vm, NULL))
+ if (!qemuMigrationIsAllowed(driver, vm, NULL, flags))
goto cleanup;
if (!(mig = qemuMigrationEatCookie(driver, vm, NULL, 0, 0)))
@@ -1078,7 +1085,8 @@ qemuMigrationPrepareAny(struct qemud_driver *driver,
const char *dname,
const char *dom_xml,
const char *migrateFrom,
- virStreamPtr st)
+ virStreamPtr st,
+ int flags)
{
virDomainDefPtr def = NULL;
virDomainObjPtr vm = NULL;
@@ -1099,7 +1107,7 @@ qemuMigrationPrepareAny(struct qemud_driver *driver,
VIR_DOMAIN_XML_INACTIVE)))
goto cleanup;
- if (!qemuMigrationIsAllowed(driver, NULL, def))
+ if (!qemuMigrationIsAllowed(driver, NULL, def, flags))
goto cleanup;
/* Target domain name, maybe renamed. */
@@ -1239,7 +1247,8 @@ qemuMigrationPrepareTunnel(struct qemud_driver *driver,
int *cookieoutlen,
virStreamPtr st,
const char *dname,
- const char *dom_xml)
+ const char *dom_xml,
+ unsigned long flags)
{
int ret;
@@ -1253,7 +1262,7 @@ qemuMigrationPrepareTunnel(struct qemud_driver *driver,
*/
ret = qemuMigrationPrepareAny(driver, dconn, cookiein, cookieinlen,
cookieout, cookieoutlen, dname, dom_xml,
- "stdio", st);
+ "stdio", st, flags);
return ret;
}
@@ -1268,7 +1277,8 @@ qemuMigrationPrepareDirect(struct qemud_driver *driver,
const char *uri_in,
char **uri_out,
const char *dname,
- const char *dom_xml)
+ const char *dom_xml,
+ unsigned long flags)
{
static int port = 0;
int this_port;
@@ -1364,7 +1374,7 @@ qemuMigrationPrepareDirect(struct qemud_driver *driver,
ret = qemuMigrationPrepareAny(driver, dconn, cookiein, cookieinlen,
cookieout, cookieoutlen, dname, dom_xml,
- migrateFrom, NULL);
+ migrateFrom, NULL, flags);
cleanup:
VIR_FREE(hostname);
if (ret != 0)
@@ -2031,7 +2041,7 @@ static int doPeer2PeerMigrate3(struct qemud_driver *driver,
* a single job. */
dom_xml = qemuMigrationBegin(driver, vm, xmlin, dname,
- &cookieout, &cookieoutlen);
+ &cookieout, &cookieoutlen, flags);
if (!dom_xml)
goto cleanup;
@@ -2308,7 +2318,7 @@ qemuMigrationPerformJob(struct qemud_driver *driver,
goto endjob;
}
- if (!qemuMigrationIsAllowed(driver, vm, NULL))
+ if (!qemuMigrationIsAllowed(driver, vm, NULL, flags))
goto cleanup;
resume = virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING;
diff --git a/src/qemu/qemu_migration.h b/src/qemu/qemu_migration.h
index f806ca1..f6491b5 100644
--- a/src/qemu/qemu_migration.h
+++ b/src/qemu/qemu_migration.h
@@ -35,7 +35,9 @@
VIR_MIGRATE_PAUSED | \
VIR_MIGRATE_NON_SHARED_DISK | \
VIR_MIGRATE_NON_SHARED_INC | \
- VIR_MIGRATE_CHANGE_PROTECTION)
+ VIR_MIGRATE_CHANGE_PROTECTION | \
+ VIR_MIGRATE_FORCE)
+
enum qemuMigrationJobPhase {
QEMU_MIGRATION_PHASE_NONE = 0,
@@ -81,7 +83,8 @@ char *qemuMigrationBegin(struct qemud_driver *driver,
const char *xmlin,
const char *dname,
char **cookieout,
- int *cookieoutlen);
+ int *cookieoutlen,
+ unsigned long flags);
int qemuMigrationPrepareTunnel(struct qemud_driver *driver,
virConnectPtr dconn,
@@ -91,7 +94,8 @@ int qemuMigrationPrepareTunnel(struct qemud_driver *driver,
int *cookieoutlen,
virStreamPtr st,
const char *dname,
- const char *dom_xml);
+ const char *dom_xml,
+ unsigned long flags);
int qemuMigrationPrepareDirect(struct qemud_driver *driver,
virConnectPtr dconn,
@@ -102,7 +106,8 @@ int qemuMigrationPrepareDirect(struct qemud_driver *driver,
const char *uri_in,
char **uri_out,
const char *dname,
- const char *dom_xml);
+ const char *dom_xml,
+ unsigned long flags);
int qemuMigrationPerform(struct qemud_driver *driver,
virConnectPtr conn,
diff --git a/src/util/virterror.c b/src/util/virterror.c
index 5006fa2..3544208 100644
--- a/src/util/virterror.c
+++ b/src/util/virterror.c
@@ -1210,6 +1210,12 @@ virErrorMsg(virErrorNumber error, const char *info)
else
errmsg = _("revert requires force: %s");
break;
+ case VIR_ERR_MIGRATE_RISKY:
+ if (info == NULL)
+ errmsg = _("migration requires force");
+ else
+ errmsg = _("migration requires force: %s");
+ break;
}
return (errmsg);
}
--
1.7.6.3
--
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