* Lukas Straub (lukasstra...@web.de) wrote:
> On Mon, 11 May 2020 17:19:09 +0100
> "Dr. David Alan Gilbert" <dgilb...@redhat.com> wrote:
>
> > * Lukas Straub (lukasstra...@web.de) wrote:
> > > Add yank option, pass it to the socket-channel and register a yank
> > > function which sets s->state = NBD_CLIENT_QUIT. This is the same
> > > behaviour as if an error occured.
> > >
> > > Signed-off-by: Lukas Straub <lukasstra...@web.de>
> >
> > > +static void nbd_yank(void *opaque)
> > > +{
> > > + BlockDriverState *bs = opaque;
> > > + BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
> > > +
> > > + atomic_set(&s->state, NBD_CLIENT_QUIT);
> >
> > I think I was expecting a shutdown on the socket here - why doesn't it
> > have one?
>
> For nbd, we register two yank functions: This one and we enable the yank
> feature on the qio channel (see function nbd_establish_connection below).
Oh I see; yeh that still surprises me a little; I'd expected one yank
per item.
Dave
> Regards,
> Lukas Straub
>
> > Dave
> >
> > > +}
> > > +
> > > static void nbd_client_close(BlockDriverState *bs)
> > > {
> > > BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
> > > @@ -1407,14 +1421,17 @@ static void nbd_client_close(BlockDriverState *bs)
> > > nbd_teardown_connection(bs);
> > > }
> > >
> > > -static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr,
> > > +static QIOChannelSocket *nbd_establish_connection(BlockDriverState *bs,
> > > + SocketAddress *saddr,
> > > Error **errp)
> > > {
> > > + BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
> > > QIOChannelSocket *sioc;
> > > Error *local_err = NULL;
> > >
> > > sioc = qio_channel_socket_new();
> > > qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client");
> > > + qio_channel_set_yank(QIO_CHANNEL(sioc), s->yank);
> > >
> > > qio_channel_socket_connect_sync(sioc, saddr, &local_err);
> > > if (local_err) {
> > > @@ -1438,7 +1455,7 @@ static int nbd_client_connect(BlockDriverState *bs,
> > > Error **errp)
> > > * establish TCP connection, return error if it fails
> > > * TODO: Configurable retry-until-timeout behaviour.
> > > */
> > > - QIOChannelSocket *sioc = nbd_establish_connection(s->saddr, errp);
> > > + QIOChannelSocket *sioc = nbd_establish_connection(bs, s->saddr,
> > > errp);
> > >
> > > if (!sioc) {
> > > return -ECONNREFUSED;
> > > @@ -1829,6 +1846,12 @@ static QemuOptsList nbd_runtime_opts = {
> > > "future requests before a successful reconnect will "
> > > "immediately fail. Default 0",
> > > },
> > > + {
> > > + .name = "yank",
> > > + .type = QEMU_OPT_BOOL,
> > > + .help = "Forcibly close the connection and don't attempt to "
> > > + "reconnect when the 'yank' qmp command is executed.",
> > > + },
> > > { /* end of list */ }
> > > },
> > > };
> > > @@ -1888,6 +1911,8 @@ static int nbd_process_options(BlockDriverState
> > > *bs, QDict *options,
> > >
> > > s->reconnect_delay = qemu_opt_get_number(opts, "reconnect-delay", 0);
> > >
> > > + s->yank = qemu_opt_get_bool(opts, "yank", false);
> > > +
> > > ret = 0;
> > >
> > > error:
> > > @@ -1921,6 +1946,10 @@ static int nbd_open(BlockDriverState *bs, QDict
> > > *options, int flags,
> > > /* successfully connected */
> > > s->state = NBD_CLIENT_CONNECTED;
> > >
> > > + if (s->yank) {
> > > + yank_register_function(nbd_yank, bs);
> > > + }
> > > +
> > > s->connection_co = qemu_coroutine_create(nbd_connection_entry, s);
> > > bdrv_inc_in_flight(bs);
> > > aio_co_schedule(bdrv_get_aio_context(bs), s->connection_co);
> > > @@ -1972,6 +2001,11 @@ static void nbd_close(BlockDriverState *bs)
> > > BDRVNBDState *s = bs->opaque;
> > >
> > > nbd_client_close(bs);
> > > +
> > > + if (s->yank) {
> > > + yank_unregister_function(nbd_yank, bs);
> > > + }
> > > +
> > > nbd_clear_bdrvstate(s);
> > > }
> > >
> > > diff --git a/qapi/block-core.json b/qapi/block-core.json
> > > index 943df1926a..1c1578160e 100644
> > > --- a/qapi/block-core.json
> > > +++ b/qapi/block-core.json
> > > @@ -3862,6 +3862,8 @@
> > > # reconnect. After that time, any delayed requests and
> > > all
> > > # future requests before a successful reconnect will
> > > # immediately fail. Default 0 (Since 4.2)
> > > +# @yank: Forcibly close the connection and don't attempt to reconnect
> > > when
> > > +# the 'yank' qmp command is executed. (Since: 5.1)
> > > #
> > > # Since: 2.9
> > > ##
> > > @@ -3870,7 +3872,8 @@
> > > '*export': 'str',
> > > '*tls-creds': 'str',
> > > '*x-dirty-bitmap': 'str',
> > > - '*reconnect-delay': 'uint32' } }
> > > + '*reconnect-delay': 'uint32',
> > > + 'yank': 'bool' } }
> > >
> > > ##
> > > # @BlockdevOptionsRaw:
> > > --
> > > 2.20.1
> > >
> >
> >
> > --
> > Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
> >
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
