/* $NetBSD: xennetback_xenbus.c,v 1.13 2007/03/04 06:01:11 christos 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Manuel Bouyer. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * 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 "opt_xen.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "bpfilter.h" #if NBPFILTER > 0 #include #include #endif #include #include #include #include #include #include #include #ifdef XENDEBUG_NET #define XENPRINTF(x) printf x #else #define XENPRINTF(x) #endif #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 */ }; static inline void xni_pkt_unmap(struct xni_pkt *, vaddr_t); /* pools for xni_pkt */ struct pool xni_pkt_pool; /* ratecheck(9) for pool allocation failures */ struct timeval xni_pool_errintvl = { 30, 0 }; /* 30s, each */ /* * Backend network device driver for Xen */ /* 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; u_int8_t xni_enaddr[ETHER_ADDR_LEN]; /* remote domain communication stuff */ unsigned int xni_evtchn; /* our even channel */ 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(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 *); SLIST_HEAD(, xnetback_instance) xnetback_instances; static struct xnetback_instance *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 /* * We will transfers a mapped page to the remote domain, and remap another * page in place immediatly. For this we keep a list of pages available. * When the list is empty, we ask the hypervisor to give us * NB_XMIT_PAGES_BATCH pages back. */ static unsigned long mcl_pages[NB_XMIT_PAGES_BATCH]; /* our physical pages */ int mcl_pages_alloc; /* current index in mcl_pages */ static int xennetback_get_mcl_page(paddr_t *); static void xennetback_get_new_mcl_pages(void); /* * If we can't transfer the mbuf directly, we have to copy it to a page which * will be transfered to the remote domain. We use a pool + pool_cache * for this, or the mbuf cluster pool cache if MCLBYTES == PAGE_SIZE */ #if MCLBYTES != PAGE_SIZE struct pool xmit_pages_pool; struct pool_cache xmit_pages_pool_cache; #endif struct pool_cache *xmit_pages_pool_cachep; /* arrays used in xennetback_ifstart(), too large to allocate on stack */ static mmu_update_t xstart_mmu[NB_XMIT_PAGES_BATCH]; static multicall_entry_t xstart_mcl[NB_XMIT_PAGES_BATCH + 1]; static gnttab_transfer_t xstart_gop[NB_XMIT_PAGES_BATCH]; struct mbuf *mbufs_sent[NB_XMIT_PAGES_BATCH]; struct _pages_pool_free { vaddr_t va; paddr_t pa; } pages_pool_free[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) { int i; struct pglist mlist; struct vm_page *pg; XENPRINTF(("xennetback_init\n")); /* * steal some non-managed pages to the VM system, to remplace * mbuf cluster or xmit_pages_pool pages given to foreing domains. */ if (uvm_pglistalloc(PAGE_SIZE * NB_XMIT_PAGES_BATCH, 0, 0xffffffff, 0, 0, &mlist, NB_XMIT_PAGES_BATCH, 0) != 0) panic("xennetback_init: uvm_pglistalloc"); for (i = 0, pg = mlist.tqh_first; pg != NULL; pg = pg->pageq.tqe_next, i++) mcl_pages[i] = xpmap_ptom(VM_PAGE_TO_PHYS(pg)) >> PAGE_SHIFT; if (i != NB_XMIT_PAGES_BATCH) panic("xennetback_init: %d mcl pages", i); mcl_pages_alloc = NB_XMIT_PAGES_BATCH - 1; /* initialise pools */ pool_init(&xni_pkt_pool, sizeof(struct xni_pkt), 0, 0, 0, "xnbpkt", NULL); #if MCLBYTES != PAGE_SIZE pool_init(&xmit_pages_pool, PAGE_SIZE, 0, 0, 0, "xnbxm", NULL); pool_cache_init(&xmit_pages_pool_cache, &xmit_pages_pool, NULL, NULL, NULL); xmit_pages_pool_cachep = &xmit_pages_pool_cache; #else xmit_pages_pool_cachep = &mclpool_cache; #endif SLIST_INIT(&xnetback_instances); 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; if ((err = xenbus_read_ul(NULL, xbusd->xbusd_path, "frontend-id", &domid, 10)) != 0) { aprint_error("xvif: can' 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' read %s/handle: %d\n", xbusd->xbusd_path, err); return err; } if (xnetif_lookup(domid, handle) != NULL) { return EEXIST; } xneti = malloc(sizeof(struct xnetback_instance), M_DEVBUF, M_NOWAIT | M_ZERO); if (xneti == NULL) { return ENOMEM; } 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; xneti->xni_softintr = softintr_establish(IPL_SOFTNET, xennetback_ifsoftstart, xneti); if (xneti->xni_softintr == NULL) { err = ENOMEM; goto fail; } ifp = &xneti->xni_if; ifp->if_softc = xneti; /* read mac address */ if ((err = xenbus_read(NULL, xbusd->xbusd_path, "mac", NULL, &val))) { aprint_error("xvif: can' 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("xvif: %s is not a valid mac address\n", val); 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 */ snprintf(xneti->xni_if.if_xname, IFNAMSIZ, "xvif%d.%d", (int)domid, (int)handle); printf("%s: Ethernet address %s\n", ifp->if_xname, ether_sprintf(xneti->xni_enaddr)); ifp->if_flags = IFF_BROADCAST|IFF_SIMPLEX|IFF_NOTRAILERS|IFF_MULTICAST; ifp->if_snd.ifq_maxlen = max(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); SLIST_INSERT_HEAD(&xnetback_instances, xneti, next); xbusd->xbusd_otherend_changed = xennetback_frontend_changed; err = xenbus_switch_state(xbusd, NULL, XenbusStateInitWait); if (err) { printf("failed to switch state on %s: %d\n", xbusd->xbusd_path, err); goto fail; } if (err) { printf("failed to write %s/hotplug-status: %d\n", xbusd->xbusd_path, err); goto fail; } return 0; fail: free(xneti, M_DEVBUF); return err; } int xennetback_xenbus_destroy(void *arg) { struct xnetback_instance *xneti = arg; struct gnttab_unmap_grant_ref op; int err; #if 0 if (xneti->xni_status == CONNECTED) { return EBUSY; } #endif printf("%s: disconnecting\n", xneti->xni_if.if_xname); hypervisor_mask_event(xneti->xni_evtchn); event_remove_handler(xneti->xni_evtchn, xennetback_evthandler, xneti); softintr_disestablish(xneti->xni_softintr); SLIST_REMOVE(&xnetback_instances, xneti, xnetback_instance, next); 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) printf("%s: unmap_grant_ref failed: %d\n", xneti->xni_if.if_xname, 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) printf("%s: unmap_grant_ref failed: %d\n", xneti->xni_if.if_xname, err); } uvm_km_free(kernel_map, xneti->xni_tx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); uvm_km_free(kernel_map, xneti->xni_rx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); free(xneti, M_DEVBUF); return 0; } static void xennetback_frontend_changed(void *arg, XenbusState new_state) { struct xnetback_instance *xneti = arg; struct xenbus_device *xbusd = xneti->xni_xbusd; int err; netif_tx_sring_t *tx_ring; netif_rx_sring_t *rx_ring; struct gnttab_map_grant_ref op; evtchn_op_t evop; u_long tx_ring_ref, rx_ring_ref; u_long revtchn; XENPRINTF(("%s: new state %d\n", xneti->xni_if.if_xname, new_state)); switch(new_state) { case XenbusStateInitialising: case XenbusStateInitialised: break; case XenbusStateConnected: /* read comunication informations */ 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); break; } 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); break; } 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); break; } /* 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); break; } 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) { printf("%s: can't map TX grant ref: %d/%d\n", xneti->xni_if.if_xname, err, op.status); goto err2; } xneti->xni_tx_ring_handle = op.handle; 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) { printf("%s: can't map RX grant ref: %d/%d\n", xneti->xni_if.if_xname, err, op.status); goto err2; } xneti->xni_rx_ring_handle = op.handle; BACK_RING_INIT(&xneti->xni_txring, tx_ring, PAGE_SIZE); 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) { printf("%s: can't get event channel: %d\n", xneti->xni_if.if_xname, err); goto err2; } xneti->xni_evtchn = evop.u.bind_interdomain.local_port; x86_sfence(); xneti->xni_status = CONNECTED; xenbus_switch_state(xbusd, NULL, XenbusStateConnected); x86_sfence(); event_set_handler(xneti->xni_evtchn, xennetback_evthandler, xneti, IPL_NET, xneti->xni_if.if_xname); xennetback_ifinit(&xneti->xni_if); hypervisor_enable_event(xneti->xni_evtchn); hypervisor_notify_via_evtchn(xneti->xni_evtchn); 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; err2: uvm_km_free(kernel_map, xneti->xni_rx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); err1: uvm_km_free(kernel_map, xneti->xni_tx_ring_va, PAGE_SIZE, UVM_KMF_VAONLY); } /* lookup a xneti based on domain id and interface handle */ static struct xnetback_instance * xnetif_lookup(domid_t dom , uint32_t handle) { struct xnetback_instance *xneti; SLIST_FOREACH(xneti, &xnetback_instances, next) { if (xneti->xni_domid == dom && xneti->xni_handle == handle) return xneti; } return NULL; } /* get a page to remplace a mbuf cluster page given to a domain */ static int xennetback_get_mcl_page(paddr_t *map) { if (mcl_pages_alloc < 0) /* * we exhausted our allocation. We can't allocate new ones yet * because the current pages may not have been loaned to * the remote domain yet. We have to let the caller do this. */ return -1; *map = mcl_pages[mcl_pages_alloc] << PAGE_SHIFT; mcl_pages_alloc--; return 0; } static void xennetback_get_new_mcl_pages(void) { int nb_pages; struct xen_memory_reservation res; /* get some new pages. */ res.extent_start = mcl_pages; res.nr_extents = NB_XMIT_PAGES_BATCH; res.extent_order = 0; res.address_bits = 0; res.domid = DOMID_SELF; nb_pages = HYPERVISOR_memory_op(XENMEM_increase_reservation, &res); if (nb_pages <= 0) { printf("xennetback: can't get new mcl pages (%d)\n", nb_pages); return; } if (nb_pages != NB_XMIT_PAGES_BATCH) printf("xennetback: got only %d new mcl pages\n", nb_pages); mcl_pages_alloc = nb_pages - 1; } 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 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; x86_lfence(); while (1) { x86_lfence(); /* be sure to read the request before updating */ xneti->xni_txring.req_cons = req_cons; x86_sfence(); RING_FINAL_CHECK_FOR_REQUESTS(&xneti->xni_txring, receive_pending); if (receive_pending == 0) break; txreq = RING_GET_REQUEST(&xneti->xni_txring, req_cons); x86_lfence(); 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. */ if (__predict_false(txreq->size < ETHER_HDR_LEN || txreq->size > (ETHER_MAX_LEN - ETHER_CRC_LEN))) { printf("%s: packet size %d too big\n", ifp->if_xname, txreq->size); xennetback_tx_response(xneti, txreq->id, NETIF_RSP_ERROR); ifp->if_ierrors++; continue; } /* don't cross page boundaries */ if (__predict_false( txreq->offset + txreq->size > PAGE_SIZE)) { printf("%s: packet cross page boundary\n", ifp->if_xname); 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(LLADDR(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 = min(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->m_pkthdr.rcvif = ifp; ifp->if_ipackets++; #if NBPFILTER > 0 if (ifp->if_bpf) bpf_mtap(ifp->if_bpf, m); #endif (*ifp->if_input)(ifp, m); } x86_lfence(); /* be sure to read the request before updating pointer */ xneti->xni_txring.req_cons = req_cons; x86_sfence(); /* check to see if we can transmit more packets */ softintr_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(&mbpool_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 xennet_softstart(). */ softintr_schedule(xneti->xni_softintr); } static void xennetback_ifsoftstart(void *arg) { struct xnetback_instance *xneti = arg; struct ifnet *ifp = &xneti->xni_if; struct mbuf *m; vaddr_t xmit_va; paddr_t xmit_pa; paddr_t xmit_ma; paddr_t newp_ma = 0; /* XXX gcc */ int i, j, nppitems; mmu_update_t *mmup; multicall_entry_t *mclp; netif_rx_response_t *rxresp; RING_IDX req_prod, resp_prod; int do_event = 0; gnttab_transfer_t *gop; int id, offset; XENPRINTF(("xennetback_ifsoftstart ")); 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; x86_lfence(); mmup = xstart_mmu; mclp = xstart_mcl; gop = xstart_gop; for (nppitems = 0, 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)); ifp->if_timer = 1; break; } if (__predict_false(i == NB_XMIT_PAGES_BATCH)) break; /* we filled the array */ if (__predict_false( xennetback_get_mcl_page(&newp_ma) != 0)) break; /* out of memory */ if ((m->m_flags & M_CLUSTER) != 0 && !M_READONLY(m) && MCLBYTES == PAGE_SIZE) { /* we can give this page away */ xmit_pa = m->m_ext.ext_paddr; xmit_ma = xpmap_ptom(xmit_pa); xmit_va = (vaddr_t)m->m_ext.ext_buf; KASSERT(xmit_pa != M_PADDR_INVALID); KASSERT((xmit_va & PAGE_MASK) == 0); offset = m->m_data - m->m_ext.ext_buf; } else { /* we have to copy the packet */ xmit_va = (vaddr_t)pool_cache_get_paddr( xmit_pages_pool_cachep, PR_NOWAIT, &xmit_pa); if (__predict_false(xmit_va == 0)) break; /* out of memory */ KASSERT(xmit_pa != POOL_PADDR_INVALID); xmit_ma = xpmap_ptom(xmit_pa); XENPRINTF(("xennetback_get_xmit_page: got va " "0x%x ma 0x%x\n", (u_int)xmit_va, (u_int)xmit_ma)); m_copydata(m, 0, m->m_pkthdr.len, (void *)xmit_va + LINUX_REQUESTED_OFFSET); offset = LINUX_REQUESTED_OFFSET; pages_pool_free[nppitems].va = xmit_va; pages_pool_free[nppitems].pa = xmit_pa; nppitems++; } /* start filling ring */ gop->ref = RING_GET_REQUEST(&xneti->xni_rxring, xneti->xni_rxring.req_cons)->gref; id = RING_GET_REQUEST(&xneti->xni_rxring, xneti->xni_rxring.req_cons)->id; x86_lfence(); xneti->xni_rxring.req_cons++; rxresp = RING_GET_RESPONSE(&xneti->xni_rxring, resp_prod); rxresp->id = id; rxresp->offset = offset; 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; } /* * transfers the page containing the packet to the * remote domain, and map newp in place. */ xpmap_phys_to_machine_mapping[ (xmit_pa - XPMAP_OFFSET) >> PAGE_SHIFT] = newp_ma >> PAGE_SHIFT; MULTI_update_va_mapping(mclp, xmit_va, newp_ma | PG_V | PG_RW | PG_U | PG_M, 0); mclp++; gop->mfn = xmit_ma >> PAGE_SHIFT; gop->domid = xneti->xni_domid; gop++; mmup->ptr = newp_ma | MMU_MACHPHYS_UPDATE; mmup->val = (xmit_pa - XPMAP_OFFSET) >> PAGE_SHIFT; mmup++; /* done with this packet */ IFQ_DEQUEUE(&ifp->if_snd, m); mbufs_sent[i] = m; resp_prod++; i++; /* this packet has been queued */ ifp->if_opackets++; #if NBPFILTER > 0 if (ifp->if_bpf) bpf_mtap(ifp->if_bpf, m); #endif } if (i != 0) { /* * We may have allocated buffers which have entries * outstanding in the page update queue -- make sure * we flush those first! */ int svm = splvm(); xpq_flush_queue(); splx(svm); mclp[-1].args[MULTI_UVMFLAGS_INDEX] = UVMF_TLB_FLUSH|UVMF_ALL; mclp->op = __HYPERVISOR_mmu_update; mclp->args[0] = (unsigned long)xstart_mmu; mclp->args[1] = i; mclp->args[2] = 0; mclp->args[3] = DOMID_SELF; mclp++; /* update the MMU */ if (HYPERVISOR_multicall(xstart_mcl, i + 1) != 0) { panic("%s: HYPERVISOR_multicall failed", ifp->if_xname); } for (j = 0; j < i + 1; j++) { if (xstart_mcl[j].result != 0) { printf("%s: xstart_mcl[%d] " "failed (%lu)\n", ifp->if_xname, j, xstart_mcl[j].result); printf("%s: req_prod %u req_cons " "%u rsp_prod %u rsp_prod_pvt %u " "i %u\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); } } if (HYPERVISOR_grant_table_op(GNTTABOP_transfer, xstart_gop, i) != 0) { panic("%s: GNTTABOP_transfer failed", ifp->if_xname); } for (j = 0; j < i; j++) { if (xstart_gop[j].status != 0) { printf("%s GNTTABOP_transfer[%d] %d\n", ifp->if_xname, j, xstart_gop[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]); } for (j = 0; j < nppitems; j++) { pool_cache_put_paddr(xmit_pages_pool_cachep, (void *)pages_pool_free[j].va, pages_pool_free[j].pa); } } /* send event */ if (do_event) { x86_lfence(); XENPRINTF(("%s receive event\n", xneti->xni_if.if_xname)); hypervisor_notify_via_evtchn(xneti->xni_evtchn); do_event = 0; } /* check if we need to get back some pages */ if (mcl_pages_alloc < 0) { xennetback_get_new_mcl_pages(); if (mcl_pages_alloc < 0) { /* * setup the watchdog to try again, because * xennetback_ifstart() will never be called * again if queue is full. */ printf("xennetback_ifstart: no mcl_pages\n"); ifp->if_timer = 1; break; } } /* * 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( !RING_HAS_UNCONSUMED_REQUESTS(&xneti->xni_rxring))) { /* ring full */ 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, unfortunably, we don't get an interrupt from xen * on transmit) noting 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); }