[libvirt] [PATCH v3 05/14] qemu: Add support for VIR_MIGRATE_POSTCOPY flag

[Jiri Denemark]

From: Cristian Klein <cristiklein at gmail.com>

Signed-off-by: Cristian Klein <cristiklein at gmail.com>
Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---

Notes:
    Version 3:
    - no change
    
    Version 2:
    - no change

 src/qemu/qemu_migration.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++
 src/qemu/qemu_migration.h |  3 +-
 2 files changed, 78 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index fdd95c5..e9f44a5 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -2408,6 +2408,54 @@ qemuMigrationSetOption(virQEMUDriverPtr driver,
     return ret;
 }
 
+
+static int
+qemuMigrationSetPostCopy(virQEMUDriverPtr driver,
+                         virDomainObjPtr vm,
+                         bool state,
+                         qemuDomainAsyncJob job)
+{
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    int ret;
+
+    if (qemuDomainObjEnterMonitorAsync(driver, vm, job) < 0)
+        return -1;
+
+    ret = qemuMonitorGetMigrationCapability(
+                priv->mon,
+                QEMU_MONITOR_MIGRATION_CAPS_POSTCOPY);
+
+    if (ret < 0) {
+        goto cleanup;
+    } else if (ret == 0 && !state) {
+        /* Unsupported but we want it off anyway */
+        goto cleanup;
+    } else if (ret == 0) {
+        if (job == QEMU_ASYNC_JOB_MIGRATION_IN) {
+            virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                           _("Post-copy migration is not supported by "
+                             "target QEMU binary"));
+        } else {
+            virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                           _("Post-copy migration is not supported by "
+                             "source QEMU binary"));
+        }
+        ret = -1;
+        goto cleanup;
+    }
+
+    ret = qemuMonitorSetMigrationCapability(
+                priv->mon,
+                QEMU_MONITOR_MIGRATION_CAPS_POSTCOPY,
+                state);
+
+ cleanup:
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
+    return ret;
+}
+
+
 static int
 qemuMigrationWaitForSpice(virDomainObjPtr vm)
 {
@@ -3044,6 +3092,15 @@ qemuMigrationBeginPhase(virQEMUDriverPtr driver,
         !qemuMigrationIsSafe(vm->def, nmigrate_disks, migrate_disks))
         goto cleanup;
 
+    if (flags & VIR_MIGRATE_POSTCOPY &&
+        (!(flags & VIR_MIGRATE_LIVE) ||
+         flags & VIR_MIGRATE_PAUSED)) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("post-copy migration is not supported with non-live "
+                         "or paused migration"));
+        goto cleanup;
+    }
+
     if (flags & (VIR_MIGRATE_NON_SHARED_DISK | VIR_MIGRATE_NON_SHARED_INC)) {
         bool has_drive_mirror =  virQEMUCapsGet(priv->qemuCaps,
                                                 QEMU_CAPS_DRIVE_MIRROR);
@@ -3383,6 +3440,15 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
         cookieFlags = QEMU_MIGRATION_COOKIE_GRAPHICS;
     }
 
+    if (flags & VIR_MIGRATE_POSTCOPY &&
+        (!(flags & VIR_MIGRATE_LIVE) ||
+         flags & VIR_MIGRATE_PAUSED)) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("post-copy migration is not supported with non-live "
+                         "or paused migration"));
+        goto cleanup;
+    }
+
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         goto cleanup;
 
@@ -3536,6 +3602,11 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                                QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
         goto stopjob;
 
+    if (qemuMigrationSetPostCopy(driver, vm,
+                                 flags & VIR_MIGRATE_POSTCOPY,
+                                 QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
+        goto stopjob;
+
     if (mig->nbd &&
         flags & (VIR_MIGRATE_NON_SHARED_DISK | VIR_MIGRATE_NON_SHARED_INC) &&
         virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_NBD_SERVER)) {
@@ -4430,6 +4501,11 @@ qemuMigrationRun(virQEMUDriverPtr driver,
                                QEMU_ASYNC_JOB_MIGRATION_OUT) < 0)
         goto cleanup;
 
+    if (qemuMigrationSetPostCopy(driver, vm,
+                                 flags & VIR_MIGRATE_POSTCOPY,
+                                 QEMU_ASYNC_JOB_MIGRATION_OUT) < 0)
+        goto cleanup;
+
     if (qemuDomainObjEnterMonitorAsync(driver, vm,
                                        QEMU_ASYNC_JOB_MIGRATION_OUT) < 0)
         goto cleanup;
diff --git a/src/qemu/qemu_migration.h b/src/qemu/qemu_migration.h
index 2c67a02..953f96b 100644
--- a/src/qemu/qemu_migration.h
+++ b/src/qemu/qemu_migration.h
@@ -41,7 +41,8 @@
      VIR_MIGRATE_COMPRESSED |                   \
      VIR_MIGRATE_ABORT_ON_ERROR |               \
      VIR_MIGRATE_AUTO_CONVERGE |                \
-     VIR_MIGRATE_RDMA_PIN_ALL)
+     VIR_MIGRATE_RDMA_PIN_ALL |                 \
+     VIR_MIGRATE_POSTCOPY)
 
 /* All supported migration parameters and their types. */
 # define QEMU_MIGRATION_PARAMETERS                                \
-- 
2.7.2