| /* |
| * xen paravirt network card backend |
| * |
| * (c) Gerd Hoffmann <kraxel@redhat.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; under version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, see <http://www.gnu.org/licenses/>. |
| * |
| * Contributions after 2012-01-13 are licensed under the terms of the |
| * GNU GPL, version 2 or (at your option) any later version. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/cutils.h" |
| #include "qemu/log.h" |
| #include "qemu/qemu-print.h" |
| #include "qapi/qmp/qdict.h" |
| #include "qapi/error.h" |
| |
| #include <sys/socket.h> |
| #include <sys/ioctl.h> |
| #include <sys/wait.h> |
| |
| #include "net/net.h" |
| #include "net/checksum.h" |
| #include "net/util.h" |
| |
| #include "hw/xen/xen-backend.h" |
| #include "hw/xen/xen-bus-helper.h" |
| #include "hw/qdev-properties.h" |
| #include "hw/qdev-properties-system.h" |
| |
| #include "hw/xen/interface/io/netif.h" |
| #include "hw/xen/interface/io/xs_wire.h" |
| |
| #include "trace.h" |
| |
| /* ------------------------------------------------------------- */ |
| |
| struct XenNetDev { |
| struct XenDevice xendev; /* must be first */ |
| XenEventChannel *event_channel; |
| int dev; |
| int tx_work; |
| unsigned int tx_ring_ref; |
| unsigned int rx_ring_ref; |
| struct netif_tx_sring *txs; |
| struct netif_rx_sring *rxs; |
| netif_tx_back_ring_t tx_ring; |
| netif_rx_back_ring_t rx_ring; |
| NICConf conf; |
| NICState *nic; |
| }; |
| |
| typedef struct XenNetDev XenNetDev; |
| |
| #define TYPE_XEN_NET_DEVICE "xen-net-device" |
| OBJECT_DECLARE_SIMPLE_TYPE(XenNetDev, XEN_NET_DEVICE) |
| |
| /* ------------------------------------------------------------- */ |
| |
| static void net_tx_response(struct XenNetDev *netdev, netif_tx_request_t *txp, int8_t st) |
| { |
| RING_IDX i = netdev->tx_ring.rsp_prod_pvt; |
| netif_tx_response_t *resp; |
| int notify; |
| |
| resp = RING_GET_RESPONSE(&netdev->tx_ring, i); |
| resp->id = txp->id; |
| resp->status = st; |
| |
| #if 0 |
| if (txp->flags & NETTXF_extra_info) { |
| RING_GET_RESPONSE(&netdev->tx_ring, ++i)->status = NETIF_RSP_NULL; |
| } |
| #endif |
| |
| netdev->tx_ring.rsp_prod_pvt = ++i; |
| RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->tx_ring, notify); |
| if (notify) { |
| xen_device_notify_event_channel(XEN_DEVICE(netdev), |
| netdev->event_channel, NULL); |
| } |
| |
| if (i == netdev->tx_ring.req_cons) { |
| int more_to_do; |
| RING_FINAL_CHECK_FOR_REQUESTS(&netdev->tx_ring, more_to_do); |
| if (more_to_do) { |
| netdev->tx_work++; |
| } |
| } |
| } |
| |
| static void net_tx_error(struct XenNetDev *netdev, netif_tx_request_t *txp, RING_IDX end) |
| { |
| #if 0 |
| /* |
| * Hmm, why netback fails everything in the ring? |
| * Should we do that even when not supporting SG and TSO? |
| */ |
| RING_IDX cons = netdev->tx_ring.req_cons; |
| |
| do { |
| make_tx_response(netif, txp, NETIF_RSP_ERROR); |
| if (cons >= end) { |
| break; |
| } |
| txp = RING_GET_REQUEST(&netdev->tx_ring, cons++); |
| } while (1); |
| netdev->tx_ring.req_cons = cons; |
| netif_schedule_work(netif); |
| netif_put(netif); |
| #else |
| net_tx_response(netdev, txp, NETIF_RSP_ERROR); |
| #endif |
| } |
| |
| static bool net_tx_packets(struct XenNetDev *netdev) |
| { |
| bool done_something = false; |
| netif_tx_request_t txreq; |
| RING_IDX rc, rp; |
| void *page; |
| void *tmpbuf = NULL; |
| |
| assert(bql_locked()); |
| |
| for (;;) { |
| rc = netdev->tx_ring.req_cons; |
| rp = netdev->tx_ring.sring->req_prod; |
| xen_rmb(); /* Ensure we see queued requests up to 'rp'. */ |
| |
| while ((rc != rp)) { |
| if (RING_REQUEST_CONS_OVERFLOW(&netdev->tx_ring, rc)) { |
| break; |
| } |
| memcpy(&txreq, RING_GET_REQUEST(&netdev->tx_ring, rc), sizeof(txreq)); |
| netdev->tx_ring.req_cons = ++rc; |
| done_something = true; |
| |
| #if 1 |
| /* should not happen in theory, we don't announce the * |
| * feature-{sg,gso,whatelse} flags in xenstore (yet?) */ |
| if (txreq.flags & NETTXF_extra_info) { |
| qemu_log_mask(LOG_UNIMP, "vif%u: FIXME: extra info flag\n", |
| netdev->dev); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| if (txreq.flags & NETTXF_more_data) { |
| qemu_log_mask(LOG_UNIMP, "vif%u: FIXME: more data flag\n", |
| netdev->dev); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| #endif |
| |
| if (txreq.size < 14) { |
| qemu_log_mask(LOG_GUEST_ERROR, "vif%u: bad packet size: %d\n", |
| netdev->dev, txreq.size); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| |
| if ((txreq.offset + txreq.size) > XEN_PAGE_SIZE) { |
| qemu_log_mask(LOG_GUEST_ERROR, "vif%u: error: page crossing\n", |
| netdev->dev); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| |
| trace_xen_netdev_tx(netdev->dev, txreq.gref, txreq.offset, |
| txreq.size, txreq.flags, |
| (txreq.flags & NETTXF_csum_blank) ? " csum_blank" : "", |
| (txreq.flags & NETTXF_data_validated) ? " data_validated" : "", |
| (txreq.flags & NETTXF_more_data) ? " more_data" : "", |
| (txreq.flags & NETTXF_extra_info) ? " extra_info" : ""); |
| |
| page = xen_device_map_grant_refs(&netdev->xendev, &txreq.gref, 1, |
| PROT_READ, NULL); |
| if (page == NULL) { |
| qemu_log_mask(LOG_GUEST_ERROR, |
| "vif%u: tx gref dereference failed (%d)\n", |
| netdev->dev, txreq.gref); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| if (txreq.flags & NETTXF_csum_blank) { |
| /* have read-only mapping -> can't fill checksum in-place */ |
| if (!tmpbuf) { |
| tmpbuf = g_malloc(XEN_PAGE_SIZE); |
| } |
| memcpy(tmpbuf, page + txreq.offset, txreq.size); |
| net_checksum_calculate(tmpbuf, txreq.size, CSUM_ALL); |
| qemu_send_packet(qemu_get_queue(netdev->nic), tmpbuf, |
| txreq.size); |
| } else { |
| qemu_send_packet(qemu_get_queue(netdev->nic), |
| page + txreq.offset, txreq.size); |
| } |
| xen_device_unmap_grant_refs(&netdev->xendev, page, &txreq.gref, 1, |
| NULL); |
| net_tx_response(netdev, &txreq, NETIF_RSP_OKAY); |
| } |
| if (!netdev->tx_work) { |
| break; |
| } |
| netdev->tx_work = 0; |
| } |
| g_free(tmpbuf); |
| return done_something; |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| static void net_rx_response(struct XenNetDev *netdev, |
| netif_rx_request_t *req, int8_t st, |
| uint16_t offset, uint16_t size, |
| uint16_t flags) |
| { |
| RING_IDX i = netdev->rx_ring.rsp_prod_pvt; |
| netif_rx_response_t *resp; |
| int notify; |
| |
| resp = RING_GET_RESPONSE(&netdev->rx_ring, i); |
| resp->offset = offset; |
| resp->flags = flags; |
| resp->id = req->id; |
| resp->status = (int16_t)size; |
| if (st < 0) { |
| resp->status = (int16_t)st; |
| } |
| |
| trace_xen_netdev_rx(netdev->dev, i, resp->status, resp->flags); |
| |
| netdev->rx_ring.rsp_prod_pvt = ++i; |
| RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->rx_ring, notify); |
| if (notify) { |
| xen_device_notify_event_channel(XEN_DEVICE(netdev), |
| netdev->event_channel, NULL); |
| } |
| } |
| |
| #define NET_IP_ALIGN 2 |
| |
| static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t size) |
| { |
| struct XenNetDev *netdev = qemu_get_nic_opaque(nc); |
| netif_rx_request_t rxreq; |
| RING_IDX rc, rp; |
| void *page; |
| |
| assert(bql_locked()); |
| |
| if (xen_device_backend_get_state(&netdev->xendev) != XenbusStateConnected) { |
| return -1; |
| } |
| |
| rc = netdev->rx_ring.req_cons; |
| rp = netdev->rx_ring.sring->req_prod; |
| xen_rmb(); /* Ensure we see queued requests up to 'rp'. */ |
| |
| if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) { |
| return 0; |
| } |
| if (size > XEN_PAGE_SIZE - NET_IP_ALIGN) { |
| qemu_log_mask(LOG_GUEST_ERROR, "vif%u: packet too big (%lu > %ld)", |
| netdev->dev, (unsigned long)size, |
| XEN_PAGE_SIZE - NET_IP_ALIGN); |
| return -1; |
| } |
| |
| memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq)); |
| netdev->rx_ring.req_cons = ++rc; |
| |
| page = xen_device_map_grant_refs(&netdev->xendev, &rxreq.gref, 1, |
| PROT_WRITE, NULL); |
| if (page == NULL) { |
| qemu_log_mask(LOG_GUEST_ERROR, |
| "vif%u: rx gref dereference failed (%d)\n", |
| netdev->dev, rxreq.gref); |
| net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0); |
| return -1; |
| } |
| memcpy(page + NET_IP_ALIGN, buf, size); |
| xen_device_unmap_grant_refs(&netdev->xendev, page, &rxreq.gref, 1, NULL); |
| net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0); |
| |
| return size; |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| static NetClientInfo net_xen_info = { |
| .type = NET_CLIENT_DRIVER_NIC, |
| .size = sizeof(NICState), |
| .receive = net_rx_packet, |
| }; |
| |
| static void xen_netdev_realize(XenDevice *xendev, Error **errp) |
| { |
| ERRP_GUARD(); |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| NetClientState *nc; |
| |
| qemu_macaddr_default_if_unset(&netdev->conf.macaddr); |
| |
| xen_device_frontend_printf(xendev, "mac", "%02x:%02x:%02x:%02x:%02x:%02x", |
| netdev->conf.macaddr.a[0], |
| netdev->conf.macaddr.a[1], |
| netdev->conf.macaddr.a[2], |
| netdev->conf.macaddr.a[3], |
| netdev->conf.macaddr.a[4], |
| netdev->conf.macaddr.a[5]); |
| |
| netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf, |
| object_get_typename(OBJECT(xendev)), |
| DEVICE(xendev)->id, |
| &xendev->qdev.mem_reentrancy_guard, netdev); |
| |
| nc = qemu_get_queue(netdev->nic); |
| qemu_format_nic_info_str(nc, netdev->conf.macaddr.a); |
| |
| /* fill info */ |
| xen_device_backend_printf(xendev, "feature-rx-copy", "%u", 1); |
| xen_device_backend_printf(xendev, "feature-rx-flip", "%u", 0); |
| |
| trace_xen_netdev_realize(netdev->dev, nc->info_str, nc->peer ? |
| nc->peer->name : "(none)"); |
| } |
| |
| static bool net_event(void *_xendev) |
| { |
| XenNetDev *netdev = XEN_NET_DEVICE(_xendev); |
| bool done_something; |
| |
| done_something = net_tx_packets(netdev); |
| qemu_flush_queued_packets(qemu_get_queue(netdev->nic)); |
| return done_something; |
| } |
| |
| static bool xen_netdev_connect(XenDevice *xendev, Error **errp) |
| { |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| unsigned int port, rx_copy; |
| |
| assert(bql_locked()); |
| |
| if (xen_device_frontend_scanf(xendev, "tx-ring-ref", "%u", |
| &netdev->tx_ring_ref) != 1) { |
| error_setg(errp, "failed to read tx-ring-ref"); |
| return false; |
| } |
| |
| if (xen_device_frontend_scanf(xendev, "rx-ring-ref", "%u", |
| &netdev->rx_ring_ref) != 1) { |
| error_setg(errp, "failed to read rx-ring-ref"); |
| return false; |
| } |
| |
| if (xen_device_frontend_scanf(xendev, "event-channel", "%u", |
| &port) != 1) { |
| error_setg(errp, "failed to read event-channel"); |
| return false; |
| } |
| |
| if (xen_device_frontend_scanf(xendev, "request-rx-copy", "%u", |
| &rx_copy) != 1) { |
| rx_copy = 0; |
| } |
| if (rx_copy == 0) { |
| error_setg(errp, "frontend doesn't support rx-copy"); |
| return false; |
| } |
| |
| netdev->txs = xen_device_map_grant_refs(xendev, |
| &netdev->tx_ring_ref, 1, |
| PROT_READ | PROT_WRITE, |
| errp); |
| if (!netdev->txs) { |
| error_prepend(errp, "failed to map tx grant ref: "); |
| return false; |
| } |
| |
| netdev->rxs = xen_device_map_grant_refs(xendev, |
| &netdev->rx_ring_ref, 1, |
| PROT_READ | PROT_WRITE, |
| errp); |
| if (!netdev->rxs) { |
| error_prepend(errp, "failed to map rx grant ref: "); |
| return false; |
| } |
| |
| BACK_RING_INIT(&netdev->tx_ring, netdev->txs, XEN_PAGE_SIZE); |
| BACK_RING_INIT(&netdev->rx_ring, netdev->rxs, XEN_PAGE_SIZE); |
| |
| netdev->event_channel = xen_device_bind_event_channel(xendev, port, |
| net_event, |
| netdev, |
| errp); |
| if (!netdev->event_channel) { |
| return false; |
| } |
| |
| trace_xen_netdev_connect(netdev->dev, netdev->tx_ring_ref, |
| netdev->rx_ring_ref, port); |
| |
| net_tx_packets(netdev); |
| return true; |
| } |
| |
| static void xen_netdev_disconnect(XenDevice *xendev, Error **errp) |
| { |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| |
| trace_xen_netdev_disconnect(netdev->dev); |
| |
| assert(bql_locked()); |
| |
| netdev->tx_ring.sring = NULL; |
| netdev->rx_ring.sring = NULL; |
| |
| if (netdev->event_channel) { |
| xen_device_unbind_event_channel(xendev, netdev->event_channel, |
| errp); |
| netdev->event_channel = NULL; |
| } |
| if (netdev->txs) { |
| xen_device_unmap_grant_refs(xendev, netdev->txs, |
| &netdev->tx_ring_ref, 1, errp); |
| netdev->txs = NULL; |
| } |
| if (netdev->rxs) { |
| xen_device_unmap_grant_refs(xendev, netdev->rxs, |
| &netdev->rx_ring_ref, 1, errp); |
| netdev->rxs = NULL; |
| } |
| } |
| |
| /* -------------------------------------------------------------------- */ |
| |
| |
| static void xen_netdev_frontend_changed(XenDevice *xendev, |
| enum xenbus_state frontend_state, |
| Error **errp) |
| { |
| ERRP_GUARD(); |
| enum xenbus_state backend_state = xen_device_backend_get_state(xendev); |
| |
| trace_xen_netdev_frontend_changed(xendev->name, frontend_state); |
| |
| switch (frontend_state) { |
| case XenbusStateConnected: |
| if (backend_state == XenbusStateConnected) { |
| break; |
| } |
| |
| xen_netdev_disconnect(xendev, errp); |
| if (*errp) { |
| break; |
| } |
| |
| if (!xen_netdev_connect(xendev, errp)) { |
| xen_netdev_disconnect(xendev, NULL); |
| xen_device_backend_set_state(xendev, XenbusStateClosing); |
| break; |
| } |
| |
| xen_device_backend_set_state(xendev, XenbusStateConnected); |
| break; |
| |
| case XenbusStateClosing: |
| xen_device_backend_set_state(xendev, XenbusStateClosing); |
| break; |
| |
| case XenbusStateClosed: |
| case XenbusStateUnknown: |
| xen_netdev_disconnect(xendev, errp); |
| if (*errp) { |
| break; |
| } |
| |
| xen_device_backend_set_state(xendev, XenbusStateClosed); |
| break; |
| |
| case XenbusStateInitialised: |
| /* |
| * Linux netback does nothing on the frontend going (back) to |
| * XenbusStateInitialised, so do the same here. |
| */ |
| default: |
| break; |
| } |
| } |
| |
| static char *xen_netdev_get_name(XenDevice *xendev, Error **errp) |
| { |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| |
| if (netdev->dev == -1) { |
| XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev))); |
| char fe_path[XENSTORE_ABS_PATH_MAX + 1]; |
| int idx = (xen_mode == XEN_EMULATE) ? 0 : 1; |
| char *value; |
| |
| /* Theoretically we could go up to INT_MAX here but that's overkill */ |
| while (idx < 100) { |
| snprintf(fe_path, sizeof(fe_path), |
| "/local/domain/%u/device/vif/%u", |
| xendev->frontend_id, idx); |
| value = qemu_xen_xs_read(xenbus->xsh, XBT_NULL, fe_path, NULL); |
| if (!value) { |
| if (errno == ENOENT) { |
| netdev->dev = idx; |
| goto found; |
| } |
| error_setg(errp, "cannot read %s: %s", fe_path, |
| strerror(errno)); |
| return NULL; |
| } |
| free(value); |
| idx++; |
| } |
| error_setg(errp, "cannot find device index for netdev device"); |
| return NULL; |
| } |
| found: |
| return g_strdup_printf("%u", netdev->dev); |
| } |
| |
| static void xen_netdev_unrealize(XenDevice *xendev) |
| { |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| |
| trace_xen_netdev_unrealize(netdev->dev); |
| |
| /* Disconnect from the frontend in case this has not already happened */ |
| xen_netdev_disconnect(xendev, NULL); |
| |
| if (netdev->nic) { |
| qemu_del_nic(netdev->nic); |
| } |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| static Property xen_netdev_properties[] = { |
| DEFINE_NIC_PROPERTIES(XenNetDev, conf), |
| DEFINE_PROP_INT32("idx", XenNetDev, dev, -1), |
| DEFINE_PROP_END_OF_LIST(), |
| }; |
| |
| static void xen_netdev_class_init(ObjectClass *class, void *data) |
| { |
| DeviceClass *dev_class = DEVICE_CLASS(class); |
| XenDeviceClass *xendev_class = XEN_DEVICE_CLASS(class); |
| |
| xendev_class->backend = "qnic"; |
| xendev_class->device = "vif"; |
| xendev_class->get_name = xen_netdev_get_name; |
| xendev_class->realize = xen_netdev_realize; |
| xendev_class->frontend_changed = xen_netdev_frontend_changed; |
| xendev_class->unrealize = xen_netdev_unrealize; |
| set_bit(DEVICE_CATEGORY_NETWORK, dev_class->categories); |
| dev_class->user_creatable = true; |
| |
| device_class_set_props(dev_class, xen_netdev_properties); |
| } |
| |
| static const TypeInfo xen_net_type_info = { |
| .name = TYPE_XEN_NET_DEVICE, |
| .parent = TYPE_XEN_DEVICE, |
| .instance_size = sizeof(XenNetDev), |
| .class_init = xen_netdev_class_init, |
| }; |
| |
| static void xen_net_register_types(void) |
| { |
| type_register_static(&xen_net_type_info); |
| } |
| |
| type_init(xen_net_register_types) |
| |
| /* Called to instantiate a XenNetDev when the backend is detected. */ |
| static void xen_net_device_create(XenBackendInstance *backend, |
| QDict *opts, Error **errp) |
| { |
| ERRP_GUARD(); |
| XenBus *xenbus = xen_backend_get_bus(backend); |
| const char *name = xen_backend_get_name(backend); |
| XenDevice *xendev = NULL; |
| unsigned long number; |
| const char *macstr; |
| XenNetDev *net; |
| MACAddr mac; |
| |
| if (qemu_strtoul(name, NULL, 10, &number) || number >= INT_MAX) { |
| error_setg(errp, "failed to parse name '%s'", name); |
| goto fail; |
| } |
| |
| trace_xen_netdev_create(number); |
| |
| macstr = qdict_get_try_str(opts, "mac"); |
| if (macstr == NULL) { |
| error_setg(errp, "no MAC address found"); |
| goto fail; |
| } |
| |
| if (net_parse_macaddr(mac.a, macstr) < 0) { |
| error_setg(errp, "failed to parse MAC address"); |
| goto fail; |
| } |
| |
| xendev = XEN_DEVICE(qdev_new(TYPE_XEN_NET_DEVICE)); |
| net = XEN_NET_DEVICE(xendev); |
| |
| net->dev = number; |
| memcpy(&net->conf.macaddr, &mac, sizeof(mac)); |
| |
| if (qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), errp)) { |
| xen_backend_set_device(backend, xendev); |
| return; |
| } |
| |
| error_prepend(errp, "realization of net device %lu failed: ", |
| number); |
| |
| fail: |
| if (xendev) { |
| object_unparent(OBJECT(xendev)); |
| } |
| } |
| |
| static void xen_net_device_destroy(XenBackendInstance *backend, |
| Error **errp) |
| { |
| ERRP_GUARD(); |
| XenDevice *xendev = xen_backend_get_device(backend); |
| XenNetDev *netdev = XEN_NET_DEVICE(xendev); |
| |
| trace_xen_netdev_destroy(netdev->dev); |
| |
| object_unparent(OBJECT(xendev)); |
| } |
| |
| static const XenBackendInfo xen_net_backend_info = { |
| .type = "qnic", |
| .create = xen_net_device_create, |
| .destroy = xen_net_device_destroy, |
| }; |
| |
| static void xen_net_register_backend(void) |
| { |
| xen_backend_register(&xen_net_backend_info); |
| } |
| |
| xen_backend_init(xen_net_register_backend); |
