On Thu, Oct 20, 2016 at 02:34:12PM +0200, Igor Mammedov wrote: > On Thu, 20 Oct 2016 14:13:01 +0800 > Haozhong Zhang <haozhong.zh...@intel.com> wrote: > > > If a file is used as the backend of memory-backend-file and its size is > > not identical to the property 'size', the file will be truncated. For a > > file used as the backend of vNVDIMM, its data is expected to be > > persistent and the truncation may corrupt the existing data. > I wonder if it's possible just skip 'size' property in your case instead > 'notrunc' property. That way if size is not present one'd get actual size > using get_file_size() and set 'size' to it? > And if 'size' is provided and 'size' != file_size then error out.
That works if you always want to expose the entire file, but if you intentionally only want to expose a subset you would still want to set a size (and possibly offset too) and avoid the truncation Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|
