Re: [PATCH v2 03/15] net/vhost-vdpa: Fix device compatibility check

vhost-vdpa works only with specific devices. At startup, it second guesses what the command line option handling will do and error out if it thinks a non-virtio device will attach to them. This second guessing is not only ugly, it can lead to wrong error messages ('-device floppy,netdev=foo' should complain about an unknown property, not about the wrong kind of network device being attached) and completely ignores hotplugging. Drop the old checks and implement .check_peer_type() instead to fix this. As a nice side effect, it also removes one more dependency on the legacy QemuOpts infrastructure and even reduces the code size. Signed-off-by: Kevin Wolf <kwolf(a)redhat.com&gt;

--- net/vhost-vdpa.c | 37 ++++++++++++++----------------------- 1 file changed, 14 insertions(+), 23 deletions(-) diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index 912686457c..6dc68d8677 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -147,12 +147,26 @@ static bool vhost_vdpa_has_ufo(NetClientState *nc) } +static bool vhost_vdpa_check_peer_type(NetClientState *nc, ObjectClass *oc, + Error **errp) +{ + const char *driver = object_class_get_name(oc); + + if (!g_str_has_prefix(driver, "virtio-net-")) { + error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*"); + return false; + } + + return true; +} + static NetClientInfo net_vhost_vdpa_info = { .type = NET_CLIENT_DRIVER_VHOST_VDPA, .size = sizeof(VhostVDPAState), .cleanup = vhost_vdpa_cleanup, .has_vnet_hdr = vhost_vdpa_has_vnet_hdr, .has_ufo = vhost_vdpa_has_ufo, + .check_peer_type = vhost_vdpa_check_peer_type, }; static int net_vhost_vdpa_init(NetClientState *peer, const char *device, @@ -179,24 +193,6 @@ static int net_vhost_vdpa_init(NetClientState *peer, const char *device, return ret; } -static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp) -{ - const char *name = opaque; - const char *driver, *netdev; - - driver = qemu_opt_get(opts, "driver"); - netdev = qemu_opt_get(opts, "netdev"); - if (!driver || !netdev) { - return 0; - } - if (strcmp(netdev, name) == 0 && - !g_str_has_prefix(driver, "virtio-net-")) { - error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*"); - return -1; - } - return 0; -} - int net_init_vhost_vdpa(const Netdev *netdev, const char *name, NetClientState *peer, Error **errp) { @@ -204,10 +200,5 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name, assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA); opts = &netdev->u.vhost_vdpa; - /* verify net frontend */ - if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net, - (char *)name, errp)) { - return -1; - } return net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name, opts->vhostdev); }