| /* |
| * 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 <stdio.h> |
| #include <stdlib.h> |
| #include <stdarg.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <signal.h> |
| #include <inttypes.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <sys/socket.h> |
| #include <sys/ioctl.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <sys/mman.h> |
| #include <sys/wait.h> |
| |
| #include "hw.h" |
| #include "net.h" |
| #include "net/checksum.h" |
| #include "net/util.h" |
| #include "qemu-char.h" |
| #include "xen_backend.h" |
| |
| #include <xen/io/netif.h> |
| |
| /* ------------------------------------------------------------- */ |
| |
| struct XenNetDev { |
| struct XenDevice xendev; /* must be first */ |
| char *mac; |
| int tx_work; |
| int tx_ring_ref; |
| 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; |
| }; |
| |
| /* ------------------------------------------------------------- */ |
| |
| 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_be_send_notify(&netdev->xendev); |
| } |
| |
| 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 void net_tx_packets(struct XenNetDev *netdev) |
| { |
| netif_tx_request_t txreq; |
| RING_IDX rc, rp; |
| void *page; |
| void *tmpbuf = NULL; |
| |
| 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; |
| |
| #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) { |
| xen_be_printf(&netdev->xendev, 0, "FIXME: extra info flag\n"); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| if (txreq.flags & NETTXF_more_data) { |
| xen_be_printf(&netdev->xendev, 0, "FIXME: more data flag\n"); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| #endif |
| |
| if (txreq.size < 14) { |
| xen_be_printf(&netdev->xendev, 0, "bad packet size: %d\n", txreq.size); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| |
| if ((txreq.offset + txreq.size) > XC_PAGE_SIZE) { |
| xen_be_printf(&netdev->xendev, 0, "error: page crossing\n"); |
| net_tx_error(netdev, &txreq, rc); |
| continue; |
| } |
| |
| xen_be_printf(&netdev->xendev, 3, "tx packet ref %d, off %d, len %d, flags 0x%x%s%s%s%s\n", |
| 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 = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
| netdev->xendev.dom, |
| txreq.gref, PROT_READ); |
| if (page == NULL) { |
| xen_be_printf(&netdev->xendev, 0, "error: tx gref dereference failed (%d)\n", |
| 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(XC_PAGE_SIZE); |
| } |
| memcpy(tmpbuf, page + txreq.offset, txreq.size); |
| net_checksum_calculate(tmpbuf, txreq.size); |
| qemu_send_packet(&netdev->nic->nc, tmpbuf, txreq.size); |
| } else { |
| qemu_send_packet(&netdev->nic->nc, page + txreq.offset, txreq.size); |
| } |
| xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1); |
| net_tx_response(netdev, &txreq, NETIF_RSP_OKAY); |
| } |
| if (!netdev->tx_work) { |
| break; |
| } |
| netdev->tx_work = 0; |
| } |
| g_free(tmpbuf); |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| 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; |
| } |
| |
| xen_be_printf(&netdev->xendev, 3, "rx response: idx %d, status %d, flags 0x%x\n", |
| 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_be_send_notify(&netdev->xendev); |
| } |
| } |
| |
| #define NET_IP_ALIGN 2 |
| |
| static int net_rx_ok(NetClientState *nc) |
| { |
| struct XenNetDev *netdev = DO_UPCAST(NICState, nc, nc)->opaque; |
| RING_IDX rc, rp; |
| |
| if (netdev->xendev.be_state != XenbusStateConnected) { |
| return 0; |
| } |
| |
| rc = netdev->rx_ring.req_cons; |
| rp = netdev->rx_ring.sring->req_prod; |
| xen_rmb(); |
| |
| if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) { |
| xen_be_printf(&netdev->xendev, 2, "%s: no rx buffers (%d/%d)\n", |
| __FUNCTION__, rc, rp); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t size) |
| { |
| struct XenNetDev *netdev = DO_UPCAST(NICState, nc, nc)->opaque; |
| netif_rx_request_t rxreq; |
| RING_IDX rc, rp; |
| void *page; |
| |
| if (netdev->xendev.be_state != 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)) { |
| xen_be_printf(&netdev->xendev, 2, "no buffer, drop packet\n"); |
| return -1; |
| } |
| if (size > XC_PAGE_SIZE - NET_IP_ALIGN) { |
| xen_be_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)", |
| (unsigned long)size, XC_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 = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
| netdev->xendev.dom, |
| rxreq.gref, PROT_WRITE); |
| if (page == NULL) { |
| xen_be_printf(&netdev->xendev, 0, "error: rx gref dereference failed (%d)\n", |
| rxreq.gref); |
| net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0); |
| return -1; |
| } |
| memcpy(page + NET_IP_ALIGN, buf, size); |
| xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1); |
| net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0); |
| |
| return size; |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| static NetClientInfo net_xen_info = { |
| .type = NET_CLIENT_OPTIONS_KIND_NIC, |
| .size = sizeof(NICState), |
| .can_receive = net_rx_ok, |
| .receive = net_rx_packet, |
| }; |
| |
| static int net_init(struct XenDevice *xendev) |
| { |
| struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
| |
| /* read xenstore entries */ |
| if (netdev->mac == NULL) { |
| netdev->mac = xenstore_read_be_str(&netdev->xendev, "mac"); |
| } |
| |
| /* do we have all we need? */ |
| if (netdev->mac == NULL) { |
| return -1; |
| } |
| |
| if (net_parse_macaddr(netdev->conf.macaddr.a, netdev->mac) < 0) { |
| return -1; |
| } |
| |
| netdev->conf.peer = NULL; |
| |
| netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf, |
| "xen", NULL, netdev); |
| |
| snprintf(netdev->nic->nc.info_str, sizeof(netdev->nic->nc.info_str), |
| "nic: xenbus vif macaddr=%s", netdev->mac); |
| |
| /* fill info */ |
| xenstore_write_be_int(&netdev->xendev, "feature-rx-copy", 1); |
| xenstore_write_be_int(&netdev->xendev, "feature-rx-flip", 0); |
| |
| return 0; |
| } |
| |
| static int net_connect(struct XenDevice *xendev) |
| { |
| struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
| int rx_copy; |
| |
| if (xenstore_read_fe_int(&netdev->xendev, "tx-ring-ref", |
| &netdev->tx_ring_ref) == -1) { |
| return -1; |
| } |
| if (xenstore_read_fe_int(&netdev->xendev, "rx-ring-ref", |
| &netdev->rx_ring_ref) == -1) { |
| return 1; |
| } |
| if (xenstore_read_fe_int(&netdev->xendev, "event-channel", |
| &netdev->xendev.remote_port) == -1) { |
| return -1; |
| } |
| |
| if (xenstore_read_fe_int(&netdev->xendev, "request-rx-copy", &rx_copy) == -1) { |
| rx_copy = 0; |
| } |
| if (rx_copy == 0) { |
| xen_be_printf(&netdev->xendev, 0, "frontend doesn't support rx-copy.\n"); |
| return -1; |
| } |
| |
| netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
| netdev->xendev.dom, |
| netdev->tx_ring_ref, |
| PROT_READ | PROT_WRITE); |
| netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev, |
| netdev->xendev.dom, |
| netdev->rx_ring_ref, |
| PROT_READ | PROT_WRITE); |
| if (!netdev->txs || !netdev->rxs) { |
| return -1; |
| } |
| BACK_RING_INIT(&netdev->tx_ring, netdev->txs, XC_PAGE_SIZE); |
| BACK_RING_INIT(&netdev->rx_ring, netdev->rxs, XC_PAGE_SIZE); |
| |
| xen_be_bind_evtchn(&netdev->xendev); |
| |
| xen_be_printf(&netdev->xendev, 1, "ok: tx-ring-ref %d, rx-ring-ref %d, " |
| "remote port %d, local port %d\n", |
| netdev->tx_ring_ref, netdev->rx_ring_ref, |
| netdev->xendev.remote_port, netdev->xendev.local_port); |
| |
| net_tx_packets(netdev); |
| return 0; |
| } |
| |
| static void net_disconnect(struct XenDevice *xendev) |
| { |
| struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
| |
| xen_be_unbind_evtchn(&netdev->xendev); |
| |
| if (netdev->txs) { |
| xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1); |
| netdev->txs = NULL; |
| } |
| if (netdev->rxs) { |
| xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1); |
| netdev->rxs = NULL; |
| } |
| if (netdev->nic) { |
| qemu_del_net_client(&netdev->nic->nc); |
| netdev->nic = NULL; |
| } |
| } |
| |
| static void net_event(struct XenDevice *xendev) |
| { |
| struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
| net_tx_packets(netdev); |
| } |
| |
| static int net_free(struct XenDevice *xendev) |
| { |
| struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev); |
| |
| g_free(netdev->mac); |
| return 0; |
| } |
| |
| /* ------------------------------------------------------------- */ |
| |
| struct XenDevOps xen_netdev_ops = { |
| .size = sizeof(struct XenNetDev), |
| .flags = DEVOPS_FLAG_NEED_GNTDEV, |
| .init = net_init, |
| .initialise = net_connect, |
| .event = net_event, |
| .disconnect = net_disconnect, |
| .free = net_free, |
| }; |
