[Virtio-fs] [PATCH] virtiofsd: Disable remote posix locks by default

[misono.tomohiro at fujitsu.com]

> Right now we enable remote posix locks by default. That means when guest does a posix lock it sends request to server
> (virtiofsd). But currently we only support non-blocking posix lock and return -EOPNOTSUPP for blocking version.
> 
> This means that existing applications which are doing blocking posix locks get -EOPNOTSUPP and fail. To avoid this,
> people have been running virtiosd with option "-o no_posix_lock". For new users it is still a surprise and trial and error
> takes them to this option.
> 
> Given posix lock implementation is not complete in virtiofsd, disable it by default. This means that posix locks will work
> with-in applications in a guest but not across guests. Anyway we don't support sharing filesystem among different guests
> yet in virtiofs so this should not lead to any kind of surprise or regression and will make life little easier for virtiofs users.
> 
> Reported-by: Aa Aa <jimbothom at yandex.com>
> Suggested-by: Miklos Szeredi <mszeredi at redhat.com>
> Signed-off-by: Vivek Goyal <vgoyal at redhat.com>
> ---
>  tools/virtiofsd/passthrough_ll.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

We should update docs/tools/virtiofsd.rst as well. Given that:
 Reviewed-by: Misono Tomohiro <misono.tomohiro at jp.fujitsu.com>