[libvirt PATCHv2 05/10] conf: add virtiofs-related elements and attributes

[Peter Krempa]

On Thu, Jan 23, 2020 at 18:46:06 +0100, Ján Tomko wrote:
> Add more elements for tuning the virtiofsd daemon
> and the vhost-user-fs device:
> 
>   <driver type='virtiofs' queue='1024' xattr='on'>
>     <binary>/usr/libexec/virtiofsd</binary>
>     <cache mode='always' size='2097152' unit='KiB'/>
>     <lock posix='off' flock='off'/>
>   </driver>
> 
> Signed-off-by: Ján Tomko <jtomko at redhat.com>
> ---
>  docs/formatdomain.html.in                     |  18 ++-
>  docs/schemas/domaincommon.rng                 |  51 ++++++
>  src/conf/domain_conf.c                        | 146 +++++++++++++++++-
>  src/conf/domain_conf.h                        |  16 ++
>  src/libvirt_private.syms                      |   1 +
>  .../vhost-user-fs-fd-memory.xml               |   6 +-
>  .../vhost-user-fs-hugepages.xml               |   4 +-
>  7 files changed, 238 insertions(+), 4 deletions(-)
> 
> diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
> index 21f2a92ed6..cfdb1a7a9a 100644
> --- a/docs/formatdomain.html.in
> +++ b/docs/formatdomain.html.in
> @@ -3922,10 +3922,15 @@
>      <readonly/>
>    </filesystem>
>    <filesystem type='mount' accessmode='passthrough'>
> -      <driver type='virtiofs'/>
> +      <driver type='virtiofs queue='1024' xattr='on''>
> +         <binary>/usr/libexec/virtiofsd</binary>
> +         <cache mode='always' size='2097152' unit='KiB'/>
> +         <lock posix='off' flock='off'/>

So while looking at the rest of the series, I've noticed that the
locking options are actually for the daemon and not for the device,
while caching is passed to the device.

This means that we mix semantically different options here and
additionally with a possible rewrite of the daemon the daemon-based
options may become obsolete.

I'd suggest you add them into a container along with a tag of which
version or name of virtiofsd is used.