From 9c2fd182a02d64004e30900c52e3fcdb550de0bd Mon Sep 17 00:00:00 2001
Message-Id: <9c2fd182a02d64004e30900c52e3fcdb550de0bd@dist-git>
From: Jiri Denemark <jdenemar@redhat.com>
Date: Wed, 22 Jun 2022 16:35:50 +0200
Subject: [PATCH] Add VIR_MIGRATE_ZEROCOPY flag
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The flag can be used to enable zero-copy mechanism for migrating memory
pages.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit 8744beecb36600e773c8a8c4823db2bf4b3e262d)

https://bugzilla.redhat.com/show_bug.cgi?id=2089433

Conflicts:
	include/libvirt/libvirt-domain.h
            - post-copy recovery not backported

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 include/libvirt/libvirt-domain.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 5f0a9b7572..792973ce2d 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -860,6 +860,14 @@ typedef enum {
       */
     VIR_MIGRATE_NON_SHARED_SYNCHRONOUS_WRITES = (1 << 18),
 
+    /* Use zero-copy mechanism for migrating memory pages. For QEMU/KVM this
+     * means QEMU will be temporarily allowed to lock all guest pages in host's
+     * memory, although only those that are queued for transfer will be locked
+     * at the same time.
+     *
+     * Since: 8.5.0
+     */
+    VIR_MIGRATE_ZEROCOPY = (1 << 20),
 } virDomainMigrateFlags;
 
 
-- 
2.35.1