/* $NetBSD: xennetback_xenbus.c,v 1.75.4.2 2021/02/24 08:05:08 martin Exp $ */ /* * Copyright (c) 2006 Manuel Bouyer. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: xennetback_xenbus.c,v 1.75.4.2 2021/02/24 08:05:08 martin Exp $"); #include "opt_xen.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Backend network device driver for Xen. */ #ifdef XENDEBUG_NET #define XENPRINTF(x) printf x #else #define XENPRINTF(x) #endif extern pt_entry_t xpmap_pg_nx; #define NET_TX_RING_SIZE __RING_SIZE((netif_tx_sring_t *)0, PAGE_SIZE) #define NET_RX_RING_SIZE __RING_SIZE((netif_rx_sring_t *)0, PAGE_SIZE) /* linux wants at last 16 bytes free in front of the packet */ #define LINUX_REQUESTED_OFFSET 16 /* hash list for TX requests */ /* descriptor of a packet being handled by the kernel */ struct xni_pkt { int pkt_id; /* packet's ID */ grant_handle_t pkt_handle; struct xnetback_instance *pkt_xneti; /* pointer back to our softc */ }; /* pools for xni_pkt */ struct pool xni_pkt_pool; /* ratecheck(9) for pool allocation failures */ struct timeval xni_pool_errintvl = { 30, 0 }; /* 30s, each */ /* state of a xnetback instance */ typedef enum { CONNECTED, DISCONNECTING, DISCONNECTED } xnetback_state_t; /* we keep the xnetback instances in a linked list */ struct xnetback_instance { SLIST_ENTRY(xnetback_instance) next; struct xenbus_device *xni_xbusd; /* our xenstore entry */ domid_t xni_domid; /* attached to this domain */ uint32_t xni_handle; /* domain-specific handle */ xnetback_state_t xni_status; void *xni_softintr; /* network interface stuff */ struct ethercom xni_ec; struct callout xni_restart; uint8_t xni_enaddr[ETHER_ADDR_LEN]; /* remote domain communication stuff */ unsigned int xni_evtchn; /* our event channel */ struct intrhand *xni_ih; netif_tx_back_ring_t xni_txring; netif_rx_back_ring_t xni_rxring; grant_handle_t xni_tx_ring_handle; /* to unmap the ring */ grant_handle_t xni_rx_ring_handle; vaddr_t xni_tx_ring_va; /* to unmap the ring */ vaddr_t xni_rx_ring_va; }; #define xni_if xni_ec.ec_if #define xni_bpf xni_if.if_bpf void xvifattach(int); static int xennetback_ifioctl(struct ifnet *, u_long, void *); static void xennetback_ifstart(struct ifnet *); static void xennetback_ifsoftstart_copy(void *); static void xennetback_ifwatchdog(struct ifnet *); static int xennetback_ifinit(struct ifnet *); static void xennetback_ifstop(struct ifnet *, int); static int xennetback_xenbus_create(struct xenbus_device *); static int xennetback_xenbus_destroy(void *); static void xennetback_frontend_changed(void *, XenbusState); static inline void xennetback_tx_response(struct xnetback_instance *, int, int); static void xennetback_tx_free(struct mbuf * , void *, size_t, void *); static SLIST_HEAD(, xnetback_instance) xnetback_instances; static kmutex_t xnetback_lock; static bool xnetif_lookup(domid_t, uint32_t); static int xennetback_evthandler(void *); static struct xenbus_backend_driver xvif_backend_driver = { .xbakd_create = xennetback_xenbus_create, .xbakd_type = "vif" }; /* * Number of packets to transmit in one hypercall (= number of pages to * transmit at once). */ #define NB_XMIT_PAGES_BATCH 64 /* arrays used in xennetback_ifstart(), too large to allocate on stack */ /* XXXSMP */ static gnttab_copy_t xstart_gop_copy[NB_XMIT_PAGES_BATCH]; static struct mbuf *mbufs_sent[NB_XMIT_PAGES_BATCH]; static inline void xni_pkt_unmap(struct xni_pkt *pkt, vaddr_t pkt_va) { xen_shm_unmap(pkt_va, 1, &pkt->pkt_handle); pool_put(&xni_pkt_pool, pkt); } void xvifattach(int n) { XENPRINTF(("xennetback_init\n")); /* initialise pools */ pool_init(&xni_pkt_pool, sizeof(struct xni_pkt), 0, 0, 0, "xnbpkt", NULL, IPL_VM); SLIST_INIT(&xnetback_instances); mutex_init(&xnetback_lock, MUTEX_DEFAULT, IPL_NONE); xenbus_backend_register(&xvif_backend_driver); } static int xennetback_xenbus_create(struct xenbus_device *xbusd) { struct xnetback_instance *xneti; long domid, handle; struct ifnet *ifp; extern int ifqmaxlen; /* XXX */ char *val, *e, *p; int i, err; struct xenbus_transaction *xbt; if ((err = xenbus_read_ul(NULL, xbusd->xbusd_path, "frontend-id", &domid, 10)) != 0) { aprint_error("xvif: can't read %s/frontend-id: %d\n", xbusd->xbusd_path, err); return err; } if ((err = xenbus_read_ul(NULL, xbusd->xbusd_path, "handle", &handle, 10)) != 0) { aprint_error("xvif: can't read %s/handle: %d\n", xbusd->xbusd_path, err); return err; } if (xnetif_lookup(domid, handle)) { return EEXIST; } xneti = kmem_zalloc(sizeof(*xneti), KM_SLEEP); xneti->xni_domid = domid; xneti->xni_handle = handle; xneti->xni_status = DISCONNECTED; xbusd->xbusd_u.b.b_cookie = xneti; xbusd->xbusd_u.b.b_detach = xennetback_xenbus_destroy; xneti->xni_xbusd = xbusd; ifp = &xneti->xni_if; ifp->if_softc = xneti; snprintf(ifp->if_xname, IFNAMSIZ, "xvif%di%d", (int)domid, (int)handle); /* read mac address */ if ((err = xenbus_read(NULL, xbusd->xbusd_path, "mac", NULL, &val))) { aprint_error_ifnet(ifp, "can't read %s/mac: %d\n", xbusd->xbusd_path, err); goto fail; } for (i = 0, p = val; i < 6; i++) { xneti->xni_enaddr[i] = strtoul(p, &e, 16); if ((e[0] == '\0' && i != 5) && e[0] != ':') { aprint_error_ifnet(ifp, "%s is not a valid mac address\n", val); free(val, M_DEVBUF); err = EINVAL; goto fail; } p = &e[1]; } free(val, M_DEVBUF); /* we can't use the same MAC addr as our guest */ xneti->xni_enaddr[3]++; /* create pseudo-interface */ aprint_verbose_ifnet(ifp, "Ethernet address %s\n", ether_sprintf(xneti->xni_enaddr)); xneti->xni_ec.ec_capabilities |= ETHERCAP_VLAN_MTU; ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; ifp->if_snd.ifq_maxlen = uimax(ifqmaxlen, NET_TX_RING_SIZE * 2); ifp->if_capabilities = IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_UDPv4_Tx; ifp->if_ioctl = xennetback_ifioctl; ifp->if_start = xennetback_ifstart; ifp->if_watchdog = xennetback_ifwatchdog; ifp->if_init = xennetback_ifinit; ifp->if_stop = xennetback_ifstop; ifp->if_timer = 0; IFQ_SET_READY(&ifp->if_snd); if_attach(ifp); ether_ifattach(&xneti->xni_if, xneti->xni_enaddr); mutex_enter(&xnetback_lock); SLIST_INSERT_HEAD(&xnetback_instances, xneti, next); mutex_exit(&xnetback_lock); xbusd->xbusd_otherend_changed = xennetback_frontend_changed; do { xbt = xenbus_transaction_start(); if (xbt == NULL) { aprint_error_ifnet(ifp, "%s: can't start transaction\n", xbusd->xbusd_path); goto fail; } err = xenbus_printf(xbt, xbusd->xbusd_path, "vifname", "%s", ifp->if_xname); if (err) { aprint_error_ifnet(ifp, "failed to write %s/vifname: %d\n", xbusd->xbusd_path, err); goto abort_xbt; } err = xenbus_printf(xbt, xbusd->xbusd_path, "feature-rx-copy", "%d", 1); if (err) { aprint_error_ifnet(ifp, "failed to write %s/feature-rx-copy: %d\n", xbusd->xbusd_path, err); goto abort_xbt; } } while ((err = xenbus_transaction_end(xbt, 0)) == EAGAIN); if (err) { aprint_error_ifnet(ifp, "%s: can't end transaction: %d\n", xbusd->xbusd_path, err); } err = xenbus_switch_state(xbusd, NULL, XenbusStateInitWait); if (err) { aprint_error_ifnet(ifp, "failed to switch state on %s: %d\n", xbusd->xbusd_path, err); goto fail; } return 0; abort_xbt: xenbus_transaction_end(xbt, 1); fail: kmem_free(xneti, sizeof(*xneti)); return err; } int xennetback_xenbus_destroy(void *arg) { struct xnetback_instance *xneti = arg; struct gnttab_unmap_grant_ref op; int err; aprint_verbose_ifnet(&xneti->xni_if, "disconnecting\n"); if (xneti->xni_ih != NULL) { hypervisor_mask_event(xneti->xni_evtchn); xen_intr_disestablish(xneti->xni_ih); xneti->xni_ih = NULL; if (xneti->xni_softintr) { softint_disestablish(xneti->xni_softintr); xneti->xni_softintr = NULL; } } mutex_enter(&xnetback_lock); SLIST_REMOVE(&xnetback_instances, xneti, xnetback_instance, next); mutex_exit(&xnetback_lock); ether_ifdetach(&xneti->xni_if); if_detach(&xneti->xni_if); if (xneti->xni_txring.sring) { op.host_addr = xneti->xni_tx_ring_va; op.handle = xneti->xni_tx_ring_handle; op.dev_bus_addr = 0; err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1); if (err) aprint_error_ifnet(&xneti->xni_if, "unmap_grant_ref failed: %d\n", err); } if (xneti->xni_rxring.sring) { op.host_addr = xneti->xni_rx_ring_va; op.handle = xneti->xni_rx_ring_handle; op.dev_bus_addr = 0; err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1); if (err) aprint_error_ifnet(&xneti->xni_if, "unmap_grant_ref failed: %d\n", err); } if (xneti->xni_tx_ring_va != 0) { uvm_km_free(kernel_map, xneti->xni_tx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); xneti->xni_tx_ring_va = 0; } if (xneti->xni_rx_ring_va != 0) { uvm_km_free(kernel_map, xneti->xni_rx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); xneti->xni_rx_ring_va = 0; } kmem_free(xneti, sizeof(*xneti)); return 0; } static int xennetback_connect(struct xnetback_instance *xneti) { int err; netif_tx_sring_t *tx_ring; netif_rx_sring_t *rx_ring; struct gnttab_map_grant_ref op; struct gnttab_unmap_grant_ref uop; evtchn_op_t evop; u_long tx_ring_ref, rx_ring_ref; u_long revtchn, rx_copy; struct xenbus_device *xbusd = xneti->xni_xbusd; /* read communication information */ err = xenbus_read_ul(NULL, xbusd->xbusd_otherend, "tx-ring-ref", &tx_ring_ref, 10); if (err) { xenbus_dev_fatal(xbusd, err, "reading %s/tx-ring-ref", xbusd->xbusd_otherend); return -1; } err = xenbus_read_ul(NULL, xbusd->xbusd_otherend, "rx-ring-ref", &rx_ring_ref, 10); if (err) { xenbus_dev_fatal(xbusd, err, "reading %s/rx-ring-ref", xbusd->xbusd_otherend); return -1; } err = xenbus_read_ul(NULL, xbusd->xbusd_otherend, "event-channel", &revtchn, 10); if (err) { xenbus_dev_fatal(xbusd, err, "reading %s/event-channel", xbusd->xbusd_otherend); return -1; } err = xenbus_read_ul(NULL, xbusd->xbusd_otherend, "request-rx-copy", &rx_copy, 10); if (err == ENOENT || !rx_copy) { xenbus_dev_fatal(xbusd, err, "%s/request-rx-copy not supported by frontend", xbusd->xbusd_otherend); return -1; } else if (err) { xenbus_dev_fatal(xbusd, err, "reading %s/request-rx-copy", xbusd->xbusd_otherend); return -1; } xneti->xni_softintr = softint_establish(SOFTINT_NET, xennetback_ifsoftstart_copy, xneti); if (xneti->xni_softintr == NULL) { err = ENOMEM; xenbus_dev_fatal(xbusd, ENOMEM, "can't allocate softint", xbusd->xbusd_otherend); return -1; } /* allocate VA space and map rings */ xneti->xni_tx_ring_va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0, UVM_KMF_VAONLY); if (xneti->xni_tx_ring_va == 0) { xenbus_dev_fatal(xbusd, ENOMEM, "can't get VA for TX ring", xbusd->xbusd_otherend); goto err1; } tx_ring = (void *)xneti->xni_tx_ring_va; xneti->xni_rx_ring_va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0, UVM_KMF_VAONLY); if (xneti->xni_rx_ring_va == 0) { xenbus_dev_fatal(xbusd, ENOMEM, "can't get VA for RX ring", xbusd->xbusd_otherend); goto err1; } rx_ring = (void *)xneti->xni_rx_ring_va; op.host_addr = xneti->xni_tx_ring_va; op.flags = GNTMAP_host_map; op.ref = tx_ring_ref; op.dom = xneti->xni_domid; err = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1); if (err || op.status) { aprint_error_ifnet(&xneti->xni_if, "can't map TX grant ref: err %d status %d\n", err, op.status); goto err2; } xneti->xni_tx_ring_handle = op.handle; BACK_RING_INIT(&xneti->xni_txring, tx_ring, PAGE_SIZE); op.host_addr = xneti->xni_rx_ring_va; op.flags = GNTMAP_host_map; op.ref = rx_ring_ref; op.dom = xneti->xni_domid; err = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1); if (err || op.status) { aprint_error_ifnet(&xneti->xni_if, "can't map RX grant ref: err %d status %d\n", err, op.status); goto err2; } xneti->xni_rx_ring_handle = op.handle; BACK_RING_INIT(&xneti->xni_rxring, rx_ring, PAGE_SIZE); evop.cmd = EVTCHNOP_bind_interdomain; evop.u.bind_interdomain.remote_dom = xneti->xni_domid; evop.u.bind_interdomain.remote_port = revtchn; err = HYPERVISOR_event_channel_op(&evop); if (err) { aprint_error_ifnet(&xneti->xni_if, "can't get event channel: %d\n", err); goto err2; } xneti->xni_evtchn = evop.u.bind_interdomain.local_port; xen_wmb(); xneti->xni_status = CONNECTED; xen_wmb(); xneti->xni_ih = xen_intr_establish_xname(-1, &xen_pic, xneti->xni_evtchn, IST_LEVEL, IPL_NET, xennetback_evthandler, xneti, false, xneti->xni_if.if_xname); KASSERT(xneti->xni_ih != NULL); xennetback_ifinit(&xneti->xni_if); hypervisor_unmask_event(xneti->xni_evtchn); hypervisor_notify_via_evtchn(xneti->xni_evtchn); return 0; err2: /* unmap rings */ if (xneti->xni_tx_ring_handle != 0) { uop.host_addr = xneti->xni_tx_ring_va; uop.handle = xneti->xni_tx_ring_handle; uop.dev_bus_addr = 0; err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &uop, 1); if (err) aprint_error_ifnet(&xneti->xni_if, "unmap_grant_ref failed: %d\n", err); } if (xneti->xni_rx_ring_handle != 0) { uop.host_addr = xneti->xni_rx_ring_va; uop.handle = xneti->xni_rx_ring_handle; uop.dev_bus_addr = 0; err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &uop, 1); if (err) aprint_error_ifnet(&xneti->xni_if, "unmap_grant_ref failed: %d\n", err); } err1: /* free rings VA space */ if (xneti->xni_rx_ring_va != 0) uvm_km_free(kernel_map, xneti->xni_rx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); if (xneti->xni_tx_ring_va != 0) uvm_km_free(kernel_map, xneti->xni_tx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); softint_disestablish(xneti->xni_softintr); return -1; } static void xennetback_frontend_changed(void *arg, XenbusState new_state) { struct xnetback_instance *xneti = arg; struct xenbus_device *xbusd = xneti->xni_xbusd; XENPRINTF(("%s: new state %d\n", xneti->xni_if.if_xname, new_state)); switch(new_state) { case XenbusStateInitialising: case XenbusStateInitialised: break; case XenbusStateConnected: if (xneti->xni_status == CONNECTED) break; if (xennetback_connect(xneti) == 0) xenbus_switch_state(xbusd, NULL, XenbusStateConnected); break; case XenbusStateClosing: xneti->xni_status = DISCONNECTING; xneti->xni_if.if_flags &= ~(IFF_RUNNING | IFF_OACTIVE); xneti->xni_if.if_timer = 0; xenbus_switch_state(xbusd, NULL, XenbusStateClosing); break; case XenbusStateClosed: /* otherend_changed() should handle it for us */ panic("xennetback_frontend_changed: closed\n"); case XenbusStateUnknown: case XenbusStateInitWait: default: aprint_error("%s: invalid frontend state %d\n", xneti->xni_if.if_xname, new_state); break; } return; } /* lookup a xneti based on domain id and interface handle */ static bool xnetif_lookup(domid_t dom , uint32_t handle) { struct xnetback_instance *xneti; bool found = false; mutex_enter(&xnetback_lock); SLIST_FOREACH(xneti, &xnetback_instances, next) { if (xneti->xni_domid == dom && xneti->xni_handle == handle) { found = true; break; } } mutex_exit(&xnetback_lock); return found; } static inline void xennetback_tx_response(struct xnetback_instance *xneti, int id, int status) { RING_IDX resp_prod; netif_tx_response_t *txresp; int do_event; resp_prod = xneti->xni_txring.rsp_prod_pvt; txresp = RING_GET_RESPONSE(&xneti->xni_txring, resp_prod); txresp->id = id; txresp->status = status; xneti->xni_txring.rsp_prod_pvt++; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&xneti->xni_txring, do_event); if (do_event) { XENPRINTF(("%s send event\n", xneti->xni_if.if_xname)); hypervisor_notify_via_evtchn(xneti->xni_evtchn); } } static inline const char * xennetback_tx_check_packet(const netif_tx_request_t *txreq, int vlan) { if (__predict_false(txreq->size < ETHER_HDR_LEN)) return "too small"; if (__predict_false(txreq->offset + txreq->size > PAGE_SIZE)) return "crossing a page boundary"; int maxlen = ETHER_MAX_LEN - ETHER_CRC_LEN; if (vlan) maxlen += ETHER_VLAN_ENCAP_LEN; if (__predict_false(txreq->size > maxlen)) return "too big"; return NULL; } static int xennetback_evthandler(void *arg) { struct xnetback_instance *xneti = arg; struct ifnet *ifp = &xneti->xni_if; netif_tx_request_t txreq; struct xni_pkt *pkt; vaddr_t pkt_va; struct mbuf *m; int receive_pending, err; RING_IDX req_cons; XENPRINTF(("xennetback_evthandler ")); req_cons = xneti->xni_txring.req_cons; xen_rmb(); while (1) { xen_rmb(); /* be sure to read the request before updating */ xneti->xni_txring.req_cons = req_cons; xen_wmb(); RING_FINAL_CHECK_FOR_REQUESTS(&xneti->xni_txring, receive_pending); if (receive_pending == 0) break; RING_COPY_REQUEST(&xneti->xni_txring, req_cons, &txreq); xen_rmb(); XENPRINTF(("%s pkt size %d\n", xneti->xni_if.if_xname, txreq.size)); req_cons++; if (__predict_false((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING))) { /* interface not up, drop */ xennetback_tx_response(xneti, txreq.id, NETIF_RSP_DROPPED); continue; } /* * Do some sanity checks, and map the packet's page. */ const char *msg = xennetback_tx_check_packet(&txreq, xneti->xni_ec.ec_capenable & ETHERCAP_VLAN_MTU); if (msg) { printf("%s: packet with size %d is %s\n", ifp->if_xname, txreq.size, msg); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_ERROR); ifp->if_ierrors++; continue; } /* get a mbuf for this packet */ MGETHDR(m, M_DONTWAIT, MT_DATA); if (__predict_false(m == NULL)) { static struct timeval lasttime; if (ratecheck(&lasttime, &xni_pool_errintvl)) printf("%s: mbuf alloc failed\n", ifp->if_xname); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_DROPPED); ifp->if_ierrors++; continue; } XENPRINTF(("%s pkt offset %d size %d id %d req_cons %d\n", xneti->xni_if.if_xname, txreq.offset, txreq.size, txreq.id, MASK_NETIF_TX_IDX(req_cons))); pkt = pool_get(&xni_pkt_pool, PR_NOWAIT); if (__predict_false(pkt == NULL)) { static struct timeval lasttime; if (ratecheck(&lasttime, &xni_pool_errintvl)) printf("%s: xnbpkt alloc failed\n", ifp->if_xname); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_DROPPED); ifp->if_ierrors++; m_freem(m); continue; } err = xen_shm_map(1, xneti->xni_domid, &txreq.gref, &pkt_va, &pkt->pkt_handle, XSHM_RO); if (__predict_false(err == ENOMEM)) { xennetback_tx_response(xneti, txreq.id, NETIF_RSP_DROPPED); ifp->if_ierrors++; pool_put(&xni_pkt_pool, pkt); m_freem(m); continue; } if (__predict_false(err)) { printf("%s: mapping foreing page failed: %d\n", xneti->xni_if.if_xname, err); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_ERROR); ifp->if_ierrors++; pool_put(&xni_pkt_pool, pkt); m_freem(m); continue; } if ((ifp->if_flags & IFF_PROMISC) == 0) { struct ether_header *eh = (void*)(pkt_va + txreq.offset); if (ETHER_IS_MULTICAST(eh->ether_dhost) == 0 && memcmp(CLLADDR(ifp->if_sadl), eh->ether_dhost, ETHER_ADDR_LEN) != 0) { xni_pkt_unmap(pkt, pkt_va); m_freem(m); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_OKAY); continue; /* packet is not for us */ } } #ifdef notyet /* * A lot of work is needed in the tcp stack to handle read-only * ext storage so always copy for now. */ if (((req_cons + 1) & (NET_TX_RING_SIZE - 1)) == (xneti->xni_txring.rsp_prod_pvt & (NET_TX_RING_SIZE - 1))) #else if (1) #endif /* notyet */ { /* * This is the last TX buffer. Copy the data and * ack it. Delaying it until the mbuf is * freed will stall transmit. */ m->m_len = uimin(MHLEN, txreq.size); m->m_pkthdr.len = 0; m_copyback(m, 0, txreq.size, (void *)(pkt_va + txreq.offset)); xni_pkt_unmap(pkt, pkt_va); if (m->m_pkthdr.len < txreq.size) { ifp->if_ierrors++; m_freem(m); xennetback_tx_response(xneti, txreq.id, NETIF_RSP_DROPPED); continue; } xennetback_tx_response(xneti, txreq.id, NETIF_RSP_OKAY); } else { pkt->pkt_id = txreq.id; pkt->pkt_xneti = xneti; MEXTADD(m, pkt_va + txreq.offset, txreq.size, M_DEVBUF, xennetback_tx_free, pkt); m->m_pkthdr.len = m->m_len = txreq.size; m->m_flags |= M_EXT_ROMAP; } if ((txreq.flags & NETTXF_csum_blank) != 0) { xennet_checksum_fill(&m); if (m == NULL) { ifp->if_ierrors++; continue; } } m_set_rcvif(m, ifp); if_percpuq_enqueue(ifp->if_percpuq, m); } xen_rmb(); /* be sure to read the request before updating pointer */ xneti->xni_txring.req_cons = req_cons; xen_wmb(); /* check to see if we can transmit more packets */ softint_schedule(xneti->xni_softintr); return 1; } static void xennetback_tx_free(struct mbuf *m, void *va, size_t size, void *arg) { int s = splnet(); struct xni_pkt *pkt = arg; struct xnetback_instance *xneti = pkt->pkt_xneti; XENPRINTF(("xennetback_tx_free\n")); xennetback_tx_response(xneti, pkt->pkt_id, NETIF_RSP_OKAY); xni_pkt_unmap(pkt, (vaddr_t)va & ~PAGE_MASK); if (m) pool_cache_put(mb_cache, m); splx(s); } static int xennetback_ifioctl(struct ifnet *ifp, u_long cmd, void *data) { //struct xnetback_instance *xneti = ifp->if_softc; //struct ifreq *ifr = (struct ifreq *)data; int s, error; s = splnet(); error = ether_ioctl(ifp, cmd, data); if (error == ENETRESET) error = 0; splx(s); return error; } static void xennetback_ifstart(struct ifnet *ifp) { struct xnetback_instance *xneti = ifp->if_softc; /* * The Xen communication channel is much more efficient if we can * schedule batch of packets for the domain. To achieve this, we * schedule a soft interrupt, and just return. This way, the network * stack will enqueue all pending mbufs in the interface's send queue * before it is processed by the soft interrupt handler(). */ softint_schedule(xneti->xni_softintr); } /* * sighly different from m_dup(); for some reason m_dup() can return * a chain where the data area can cross a page boundary. * This doesn't happens with the function below. */ static struct mbuf * xennetback_copymbuf(struct mbuf *m) { struct mbuf *new_m; MGETHDR(new_m, M_DONTWAIT, MT_DATA); if (__predict_false(new_m == NULL)) { return NULL; } if (m->m_pkthdr.len > MHLEN) { MCLGET(new_m, M_DONTWAIT); if (__predict_false( (new_m->m_flags & M_EXT) == 0)) { m_freem(new_m); return NULL; } } m_copydata(m, 0, m->m_pkthdr.len, mtod(new_m, void *)); new_m->m_len = new_m->m_pkthdr.len = m->m_pkthdr.len; return new_m; } /* return physical page address and offset of data area of an mbuf */ static void xennetback_mbuf_addr(struct mbuf *m, paddr_t *xmit_pa, int *offset) { switch (m->m_flags & (M_EXT|M_EXT_CLUSTER)) { case M_EXT|M_EXT_CLUSTER: KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID); *xmit_pa = m->m_ext.ext_paddr; *offset = m->m_data - m->m_ext.ext_buf; break; case 0: KASSERT(m->m_paddr != M_PADDR_INVALID); *xmit_pa = m->m_paddr; *offset = M_BUFOFFSET(m) + (m->m_data - M_BUFADDR(m)); break; default: if (__predict_false( !pmap_extract(pmap_kernel(), (vaddr_t)m->m_data, xmit_pa))) { panic("xennet_start: no pa"); } *offset = 0; break; } *offset += (*xmit_pa & ~PTE_FRAME); *xmit_pa = (*xmit_pa & PTE_FRAME); } static void xennetback_ifsoftstart_copy(void *arg) { struct xnetback_instance *xneti = arg; struct ifnet *ifp = &xneti->xni_if; struct mbuf *m, *new_m; paddr_t xmit_pa; paddr_t xmit_ma; int i, j; netif_rx_response_t *rxresp; netif_rx_request_t rxreq; RING_IDX req_prod, resp_prod; int do_event = 0; gnttab_copy_t *gop; int id, offset; bool abort; XENPRINTF(("xennetback_ifsoftstart_copy ")); int s = splnet(); if (__predict_false( (ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)) { splx(s); return; } while (!IFQ_IS_EMPTY(&ifp->if_snd)) { XENPRINTF(("pkt\n")); req_prod = xneti->xni_rxring.sring->req_prod; resp_prod = xneti->xni_rxring.rsp_prod_pvt; xen_rmb(); gop = xstart_gop_copy; abort = false; for (i = 0; !IFQ_IS_EMPTY(&ifp->if_snd);) { XENPRINTF(("have a packet\n")); IFQ_POLL(&ifp->if_snd, m); if (__predict_false(m == NULL)) panic("xennetback_ifstart: IFQ_POLL"); if (__predict_false( req_prod == xneti->xni_rxring.req_cons || xneti->xni_rxring.req_cons - resp_prod == NET_RX_RING_SIZE)) { /* out of ring space */ XENPRINTF(("xennetback_ifstart: ring full " "req_prod 0x%x req_cons 0x%x resp_prod " "0x%x\n", req_prod, xneti->xni_rxring.req_cons, resp_prod)); abort = true; break; } if (__predict_false(i == NB_XMIT_PAGES_BATCH)) break; /* we filled the array */ xennetback_mbuf_addr(m, &xmit_pa, &offset); if (m->m_pkthdr.len != m->m_len || (offset + m->m_pkthdr.len) > PAGE_SIZE) { new_m = xennetback_copymbuf(m); if (__predict_false(new_m == NULL)) { static struct timeval lasttime; if (ratecheck(&lasttime, &xni_pool_errintvl)) printf("%s: cannot allocate new mbuf\n", ifp->if_xname); abort = 1; break; } else { IFQ_DEQUEUE(&ifp->if_snd, m); m_freem(m); m = new_m; xennetback_mbuf_addr(m, &xmit_pa, &offset); } } else { IFQ_DEQUEUE(&ifp->if_snd, m); } KASSERT(xmit_pa != POOL_PADDR_INVALID); KASSERT((offset + m->m_pkthdr.len) <= PAGE_SIZE); xmit_ma = xpmap_ptom(xmit_pa); /* start filling ring */ gop->flags = GNTCOPY_dest_gref; gop->source.offset = offset; gop->source.domid = DOMID_SELF; gop->source.u.gmfn = xmit_ma >> PAGE_SHIFT; RING_COPY_REQUEST(&xneti->xni_rxring, xneti->xni_rxring.req_cons, &rxreq); gop->dest.u.ref = rxreq.gref; gop->dest.offset = 0; gop->dest.domid = xneti->xni_domid; gop->len = m->m_pkthdr.len; gop++; id = rxreq.id; xen_rmb(); xneti->xni_rxring.req_cons++; rxresp = RING_GET_RESPONSE(&xneti->xni_rxring, resp_prod); rxresp->id = id; rxresp->offset = 0; rxresp->status = m->m_pkthdr.len; if ((m->m_pkthdr.csum_flags & (M_CSUM_TCPv4 | M_CSUM_UDPv4)) != 0) { rxresp->flags = NETRXF_csum_blank; } else { rxresp->flags = 0; } mbufs_sent[i] = m; resp_prod++; i++; /* this packet has been queued */ ifp->if_opackets++; bpf_mtap(ifp, m, BPF_D_OUT); } if (i != 0) { int result; result = HYPERVISOR_grant_table_op(GNTTABOP_copy, xstart_gop_copy, i); if (result != 0) { printf("%s: GNTTABOP_copy failed %d", ifp->if_xname, result); } for (j = 0; j < i; j++) { if (result < 0 || (result > 0 && j >= result) || xstart_gop_copy[j].status != GNTST_okay){ printf("%s GNTTABOP_copy[%d] st %d\n", ifp->if_xname, j, xstart_gop_copy[j].status); printf("%s: req_prod %u req_cons " "%u rsp_prod %u rsp_prod_pvt %u " "i %d\n", ifp->if_xname, xneti->xni_rxring.sring->req_prod, xneti->xni_rxring.req_cons, xneti->xni_rxring.sring->rsp_prod, xneti->xni_rxring.rsp_prod_pvt, i); rxresp = RING_GET_RESPONSE( &xneti->xni_rxring, xneti->xni_rxring.rsp_prod_pvt + j); rxresp->status = NETIF_RSP_ERROR; } } /* update pointer */ KASSERT( xneti->xni_rxring.rsp_prod_pvt + i == resp_prod); xneti->xni_rxring.rsp_prod_pvt = resp_prod; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY( &xneti->xni_rxring, j); if (j) do_event = 1; /* now we can free the mbufs */ for (j = 0; j < i; j++) { m_freem(mbufs_sent[j]); } } /* send event */ if (do_event) { xen_rmb(); XENPRINTF(("%s receive event\n", xneti->xni_if.if_xname)); hypervisor_notify_via_evtchn(xneti->xni_evtchn); do_event = 0; } /* * note that we don't use RING_FINAL_CHECK_FOR_REQUESTS() * here, as the frontend doesn't notify when adding * requests anyway */ if (__predict_false(abort || !RING_HAS_UNCONSUMED_REQUESTS(&xneti->xni_rxring))) { /* ring full */ ifp->if_timer = 1; break; } } splx(s); } static void xennetback_ifwatchdog(struct ifnet * ifp) { /* * We can get to the following condition: transmit stalls because the * ring is full when the ifq is full too. * * In this case (as, unfortunately, we don't get an interrupt from xen * on transmit) nothing will ever call xennetback_ifstart() again. * Here we abuse the watchdog to get out of this condition. */ XENPRINTF(("xennetback_ifwatchdog\n")); xennetback_ifstart(ifp); } static int xennetback_ifinit(struct ifnet *ifp) { struct xnetback_instance *xneti = ifp->if_softc; int s = splnet(); if ((ifp->if_flags & IFF_UP) == 0) { splx(s); return 0; } if (xneti->xni_status == CONNECTED) ifp->if_flags |= IFF_RUNNING; splx(s); return 0; } static void xennetback_ifstop(struct ifnet *ifp, int disable) { struct xnetback_instance *xneti = ifp->if_softc; int s = splnet(); ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE); ifp->if_timer = 0; if (xneti->xni_status == CONNECTED) { XENPRINTF(("%s: req_prod 0x%x resp_prod 0x%x req_cons 0x%x " "event 0x%x\n", ifp->if_xname, xneti->xni_txring->req_prod, xneti->xni_txring->resp_prod, xneti->xni_txring->req_cons, xneti->xni_txring->event)); xennetback_evthandler(ifp->if_softc); /* flush pending RX requests */ } splx(s); }