[libvirt] [PATCH v1 7/7] qemu: Enable memory-backend-file.discard-data whenever possible

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1480668

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_command.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f864350bd5..67350719aa 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3148,6 +3148,12 @@ qemuBuildMemoryBackendStr(virJSONValuePtr *backendProps,
                                   NULL) < 0)
             goto cleanup;
 
+        if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE_DISCARD) &&
+            virJSONValueObjectAdd(props,
+                                  "B:discard-data", true,
+                                  NULL) < 0)
+            goto cleanup;
+
         switch (memAccess) {
         case VIR_DOMAIN_MEMORY_ACCESS_SHARED:
             if (virJSONValueObjectAdd(props, "b:share", true, NULL) < 0)
-- 
2.16.1