From f6c874e3002b944f83d887b84051654e5c5b7821 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Tue, 24 Jul 2012 16:35:04 +0100 Subject: net: Add a hub net client The vlan feature can be implemented in terms of hubs. By introducing a hub net client it becomes possible to remove the special case vlan code from net.c and push the vlan feature out of generic networking code. Signed-off-by: Stefan Hajnoczi Signed-off-by: Zhi Yong Wu Reviewed-by: Laszlo Ersek --- net/hub.c | 223 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 223 insertions(+) create mode 100644 net/hub.c (limited to 'net/hub.c') diff --git a/net/hub.c b/net/hub.c new file mode 100644 index 0000000..be6e014 --- /dev/null +++ b/net/hub.c @@ -0,0 +1,223 @@ +/* + * Hub net client + * + * Copyright IBM, Corp. 2012 + * + * Authors: + * Stefan Hajnoczi + * Zhi Yong Wu + * + * This work is licensed under the terms of the GNU LGPL, version 2 or later. + * See the COPYING.LIB file in the top-level directory. + * + */ + +#include "monitor.h" +#include "net.h" +#include "hub.h" + +/* + * A hub broadcasts incoming packets to all its ports except the source port. + * Hubs can be used to provide independent network segments, also confusingly + * named the QEMU 'vlan' feature. + */ + +typedef struct NetHub NetHub; + +typedef struct NetHubPort { + VLANClientState nc; + QLIST_ENTRY(NetHubPort) next; + NetHub *hub; + int id; +} NetHubPort; + +struct NetHub { + int id; + QLIST_ENTRY(NetHub) next; + int num_ports; + QLIST_HEAD(, NetHubPort) ports; +}; + +static QLIST_HEAD(, NetHub) hubs = QLIST_HEAD_INITIALIZER(&hubs); + +static ssize_t net_hub_receive(NetHub *hub, NetHubPort *source_port, + const uint8_t *buf, size_t len) +{ + NetHubPort *port; + + QLIST_FOREACH(port, &hub->ports, next) { + if (port == source_port) { + continue; + } + + qemu_send_packet(&port->nc, buf, len); + } + return len; +} + +static ssize_t net_hub_receive_iov(NetHub *hub, NetHubPort *source_port, + const struct iovec *iov, int iovcnt) +{ + NetHubPort *port; + ssize_t ret = 0; + + QLIST_FOREACH(port, &hub->ports, next) { + if (port == source_port) { + continue; + } + + ret = qemu_sendv_packet(&port->nc, iov, iovcnt); + } + return ret; +} + +static NetHub *net_hub_new(int id) +{ + NetHub *hub; + + hub = g_malloc(sizeof(*hub)); + hub->id = id; + hub->num_ports = 0; + QLIST_INIT(&hub->ports); + + QLIST_INSERT_HEAD(&hubs, hub, next); + + return hub; +} + +static ssize_t net_hub_port_receive(VLANClientState *nc, + const uint8_t *buf, size_t len) +{ + NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); + + return net_hub_receive(port->hub, port, buf, len); +} + +static ssize_t net_hub_port_receive_iov(VLANClientState *nc, + const struct iovec *iov, int iovcnt) +{ + NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); + + return net_hub_receive_iov(port->hub, port, iov, iovcnt); +} + +static void net_hub_port_cleanup(VLANClientState *nc) +{ + NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); + + QLIST_REMOVE(port, next); +} + +static NetClientInfo net_hub_port_info = { + .type = NET_CLIENT_OPTIONS_KIND_HUBPORT, + .size = sizeof(NetHubPort), + .receive = net_hub_port_receive, + .receive_iov = net_hub_port_receive_iov, + .cleanup = net_hub_port_cleanup, +}; + +static NetHubPort *net_hub_port_new(NetHub *hub, const char *name) +{ + VLANClientState *nc; + NetHubPort *port; + int id = hub->num_ports++; + char default_name[128]; + + if (!name) { + snprintf(default_name, sizeof(default_name), + "hub%dport%d", hub->id, id); + name = default_name; + } + + nc = qemu_new_net_client(&net_hub_port_info, NULL, NULL, "hub", name); + port = DO_UPCAST(NetHubPort, nc, nc); + port->id = id; + port->hub = hub; + + QLIST_INSERT_HEAD(&hub->ports, port, next); + + return port; +} + +/** + * Create a port on a given hub + * @name: Net client name or NULL for default name. + * + * If there is no existing hub with the given id then a new hub is created. + */ +VLANClientState *net_hub_add_port(int hub_id, const char *name) +{ + NetHub *hub; + NetHubPort *port; + + QLIST_FOREACH(hub, &hubs, next) { + if (hub->id == hub_id) { + break; + } + } + + if (!hub) { + hub = net_hub_new(hub_id); + } + + port = net_hub_port_new(hub, name); + return &port->nc; +} + +/** + * Print hub configuration + */ +void net_hub_info(Monitor *mon) +{ + NetHub *hub; + NetHubPort *port; + + QLIST_FOREACH(hub, &hubs, next) { + monitor_printf(mon, "hub %d\n", hub->id); + QLIST_FOREACH(port, &hub->ports, next) { + monitor_printf(mon, " port %d peer %s\n", port->id, + port->nc.peer ? port->nc.peer->name : ""); + } + } +} + +/** + * Get the hub id that a client is connected to + * + * @id Pointer for hub id output, may be NULL + */ +int net_hub_id_for_client(VLANClientState *nc, int *id) +{ + NetHubPort *port; + + if (nc->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) { + port = DO_UPCAST(NetHubPort, nc, nc); + } else if (nc->peer != NULL && nc->peer->info->type == + NET_CLIENT_OPTIONS_KIND_HUBPORT) { + port = DO_UPCAST(NetHubPort, nc, nc->peer); + } else { + return -ENOENT; + } + + if (id) { + *id = port->hub->id; + } + return 0; +} + +int net_init_hubport(const NetClientOptions *opts, const char *name, + VLANState *vlan) +{ + const NetdevHubPortOptions *hubport; + + assert(opts->kind == NET_CLIENT_OPTIONS_KIND_HUBPORT); + hubport = opts->hubport; + + /* The hub is a "vlan" so this option makes no sense. */ + if (vlan) { + return -EINVAL; + } + + net_hub_add_port(hubport->hubid, name); + return 0; +} -- cgit v1.1