qcow2: Tweak comment about bitmaps vs. resize

Our comment did not actually match the code.  Rewrite the comment to
be less sensitive to any future changes to qcow2-bitmap.c that might
implement scenarios that we currently reject.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200428192648.749066-4-eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

diff --git a/block/qcow2.c b/block/qcow2.c
index 3e8b3d0..ad93410 100644 (file)
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -3999,7 +3999,7 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
         goto fail;
     }
 
-    /* cannot proceed if image has bitmaps */
+    /* See qcow2-bitmap.c for which bitmap scenarios prevent a resize. */
     if (qcow2_truncate_bitmaps_check(bs, errp)) {
         ret = -ENOTSUP;
         goto fail;