diff options
author | Max Reitz <mreitz@redhat.com> | 2019-09-18 11:51:43 +0200 |
---|---|---|
committer | Max Reitz <mreitz@redhat.com> | 2019-10-28 12:08:45 +0100 |
commit | e8d04f92378c2de7b464e04469a657fd37eb29ea (patch) | |
tree | 0a274a9f3c9716def5230a4f09463e9d23fdd432 /block/qcow2.c | |
parent | e61a28a9b6b43da6a7a48f6d325fceadf9769388 (diff) |
block: Pass truncate exact=true where reasonable
This is a change in behavior, so all instances need a good
justification. The comments added here should explain my reasoning.
qed already had a comment that suggests it always expected
bdrv_truncate()/blk_truncate() to behave as if exact=true were passed
(c743849bee7 came eight months before 55b949c8476), so it was simply
broken until now.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-8-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
[mreitz: Changed comment in qed.c to explain why a new QED file must be
empty, as requested and suggested by Maxim]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/qcow2.c')
-rw-r--r-- | block/qcow2.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 9f32dae41f..7c18721741 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -5323,7 +5323,11 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, return ret; } - ret = blk_truncate(blk, new_size, false, PREALLOC_MODE_OFF, errp); + /* + * Amending image options should ensure that the image has + * exactly the given new values, so pass exact=true here. + */ + ret = blk_truncate(blk, new_size, true, PREALLOC_MODE_OFF, errp); blk_unref(blk); if (ret < 0) { return ret; |