Re: [PATCH V5 02/25] cpr: reboot mode

[Eric Blake]

On Wed, Jul 07, 2021 at 10:20:11AM -0700, Steve Sistare wrote:
> Provide the cprsave and cprload functions for live update.  These save and
> restore VM state, with minimal guest pause time, so that qemu may be updated
> to a new version in between.
> 

> +++ b/migration/cpr.c
> @@ -0,0 +1,149 @@

> +
> +QEMUFile *qf_file_open(const char *path, int flags, int mode,
> +                              const char *name, Error **errp)

Indentation is off.

> +{
> +    QIOChannelFile *fioc;
> +    QIOChannel *ioc;
> +    QEMUFile *f;
> +
> +    if (flags & O_RDWR) {
> +        error_setg(errp, "qf_file_open %s: O_RDWR not supported", path);
> +        return 0;
> +    }
> +
> +    fioc = qio_channel_file_new_path(path, flags, mode, errp);

Good, you aren't using bare open(), but reusing existing wrappers,
which means you should be able to accept magic filenames like
"/dev/fdset/1" to open an fd passed in previously.  (I had to come
back to this patch to make sure after starting on patch 3)

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org