Re: [PATCH] storage: only fallocate when allocation matches capacity

In c9ec7088 "storage: extend preallocation flags support for qemu-img" the option to fallocate was added and meant to be active when (quote): "the XML described storage <allocation> matches its <capacity>" Up until recently 81a3042a12 "storage_util: fix qemu-img sparse allocation" the compared allocation size was an order of magnitude too small, but still it does use fallocate too often unless capacity>allocation. This change fixes the comparison to match the intended description of the feature. Fixes: c9ec7088c7a3f4cd26bb471f1f243931fff6f4f9 Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1759454 Fixes: https://bugs.launchpad.net/ubuntu/focal/+source/libvirt/+bug/1847105 Signed-off-by: Christian Ehrhardt <christian.ehrhardt(a)canonical.com&gt; --- src/storage/storage_util.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/storage/storage_util.c b/src/storage/storage_util.c index cf82ea0a87..85bed76863 100644 --- a/src/storage/storage_util.c +++ b/src/storage/storage_util.c @@ -710,10 +710,10 @@ storageBackendCreateQemuImgOpts(virStorageEncryptionInfoDefPtr encinfo, virQEMUBuildQemuImgKeySecretOpts(&buf, encinfo, info->secretAlias); if (info->preallocate) { - if (info->size_arg > info->allocation) - virBufferAddLit(&buf, "preallocation=metadata,"); - else + if (info->size_arg == info->allocation) virBufferAddLit(&buf, "preallocation=falloc,"); + else + virBufferAddLit(&buf, "preallocation=metadata,"); }