[libvirt RFC] qemu_saveimage: only use wrapper when using --bypass-cache

[Claudio Fontana]

align the "save" with the "restore" code,
by only using the wrapper when using --bypass-cache.

This avoids a copy, resulting in better performance.

Signed-off-by: Claudio Fontana <cfontana at suse.de>
---
 src/qemu/qemu_saveimage.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c
index 4fd4c5cfcd..5ea1b2fbcc 100644
--- a/src/qemu/qemu_saveimage.c
+++ b/src/qemu/qemu_saveimage.c
@@ -289,8 +289,10 @@ qemuSaveImageCreate(virQEMUDriver *driver,
     if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, fd) < 0)
         goto cleanup;
 
-    if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags)))
-        goto cleanup;
+    if ((flags & VIR_DOMAIN_SAVE_BYPASS_CACHE)) {
+        if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags)))
+            goto cleanup;
+    }
 
     if (virQEMUSaveDataWrite(data, fd, path) < 0)
         goto cleanup;
-- 
2.34.1