Re: [PATCH] qsd: Document FUSE exports

[Max Reitz]

On 17.02.21 17:26, Eric Blake wrote:
> On 2/17/21 5:58 AM, Max Reitz wrote:
> > Implementing FUSE exports required no changes to the storage daemon, so
> > we forgot to document them there.  Considering that both NBD and
> > vhost-user-blk exports are documented in its man page (and NBD exports
> > in its --help text), we should probably do the same for FUSE.
> >
> > Signed-off-by: Max Reitz <mreitz@redhat.com>
> > ---
> >   docs/tools/qemu-storage-daemon.rst   | 19 +++++++++++++++++++
> >   storage-daemon/qemu-storage-daemon.c |  4 ++++
> >   2 files changed, 23 insertions(+)
>
> > @@ -142,6 +153,14 @@ domain socket ``vhost-user-blk.sock``::
> >         --blockdev driver=qcow2,node-name=qcow2,file=file \
> >         --export 
> > type=vhost-user-blk,id=export,addr.type=unix,addr.path=vhost-user-blk.sock,node-name=qcow2
> >   
> > +Export a qcow2 image file ``disk.qcow2`` via FUSE on itself, so the disk image
> > +file will then appear as a raw image::
> > +
> > +  $ qemu-storage-daemon \
> > +      --blockdev driver=file,node-name=file,filename=disk.qcow2 \
> > +      --blockdev driver=qcow2,node-name=qcow2,file=file \
> > +      --export 
> > type=fuse,id=export,node-name=qcow2,mountpoint=disk.qcow2,writable=on
> > +
>
> Should the example also mention how to unmount the file when you're done?

Just as with other exports, the export goes away when it is deleted, 
which happens e.g. when the QSD exits.  I.e., fuse_export_delete() calls 
fuse_session_unmount().

> Otherwise looks good to me.  Any documentation is better than none, even
> if we can add more, so
>
> Reviewed-by: Eric Blake <eblake@redhat.com>

Thanks!

Max