/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2004-2006 Kip Macy * Copyright (c) 2015 Wei Liu * All rights reserved. * * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.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 #include #include #include #include #include #include "xenbus_if.h" /* Features supported by all backends. TSO and LRO can be negotiated */ #define XN_CSUM_FEATURES (CSUM_TCP | CSUM_UDP) #define NET_TX_RING_SIZE __CONST_RING_SIZE(netif_tx, PAGE_SIZE) #define NET_RX_RING_SIZE __CONST_RING_SIZE(netif_rx, PAGE_SIZE) #define NET_RX_SLOTS_MIN (XEN_NETIF_NR_SLOTS_MIN + 1) /* * Should the driver do LRO on the RX end * this can be toggled on the fly, but the * interface must be reset (down/up) for it * to take effect. */ static int xn_enable_lro = 1; TUNABLE_INT("hw.xn.enable_lro", &xn_enable_lro); /* * Number of pairs of queues. */ static unsigned long xn_num_queues = 4; TUNABLE_ULONG("hw.xn.num_queues", &xn_num_queues); /** * \brief The maximum allowed data fragments in a single transmit * request. * * This limit is imposed by the backend driver. We assume here that * we are dealing with a Linux driver domain and have set our limit * to mirror the Linux MAX_SKB_FRAGS constant. */ #define MAX_TX_REQ_FRAGS (65536 / PAGE_SIZE + 2) #define RX_COPY_THRESHOLD 256 #define net_ratelimit() 0 struct netfront_rxq; struct netfront_txq; struct netfront_info; struct netfront_rx_info; static void xn_txeof(struct netfront_txq *); static void xn_rxeof(struct netfront_rxq *); static void xn_alloc_rx_buffers(struct netfront_rxq *); static void xn_alloc_rx_buffers_callout(void *arg); static void xn_release_rx_bufs(struct netfront_rxq *); static void xn_release_tx_bufs(struct netfront_txq *); static void xn_rxq_intr(struct netfront_rxq *); static void xn_txq_intr(struct netfront_txq *); static void xn_intr(void *); static inline int xn_count_frags(struct mbuf *m); static int xn_assemble_tx_request(struct netfront_txq *, struct mbuf *); static int xn_ioctl(struct ifnet *, u_long, caddr_t); static void xn_ifinit_locked(struct netfront_info *); static void xn_ifinit(void *); static void xn_stop(struct netfront_info *); static void xn_query_features(struct netfront_info *np); static int xn_configure_features(struct netfront_info *np); static void netif_free(struct netfront_info *info); static int netfront_detach(device_t dev); static int xn_txq_mq_start_locked(struct netfront_txq *, struct mbuf *); static int xn_txq_mq_start(struct ifnet *, struct mbuf *); static int talk_to_backend(device_t dev, struct netfront_info *info); static int create_netdev(device_t dev); static void netif_disconnect_backend(struct netfront_info *info); static int setup_device(device_t dev, struct netfront_info *info, unsigned long); static int xn_ifmedia_upd(struct ifnet *ifp); static void xn_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr); static int xn_connect(struct netfront_info *); static void xn_kick_rings(struct netfront_info *); static int xn_get_responses(struct netfront_rxq *, struct netfront_rx_info *, RING_IDX, RING_IDX *, struct mbuf **); #define virt_to_mfn(x) (vtophys(x) >> PAGE_SHIFT) #define INVALID_P2M_ENTRY (~0UL) #define XN_QUEUE_NAME_LEN 8 /* xn{t,r}x_%u, allow for two digits */ struct netfront_rxq { struct netfront_info *info; u_int id; char name[XN_QUEUE_NAME_LEN]; struct mtx lock; int ring_ref; netif_rx_front_ring_t ring; xen_intr_handle_t xen_intr_handle; grant_ref_t gref_head; grant_ref_t grant_ref[NET_RX_RING_SIZE + 1]; struct mbuf *mbufs[NET_RX_RING_SIZE + 1]; struct lro_ctrl lro; struct callout rx_refill; }; struct netfront_txq { struct netfront_info *info; u_int id; char name[XN_QUEUE_NAME_LEN]; struct mtx lock; int ring_ref; netif_tx_front_ring_t ring; xen_intr_handle_t xen_intr_handle; grant_ref_t gref_head; grant_ref_t grant_ref[NET_TX_RING_SIZE + 1]; struct mbuf *mbufs[NET_TX_RING_SIZE + 1]; int mbufs_cnt; struct buf_ring *br; struct taskqueue *tq; struct task defrtask; bool full; }; struct netfront_info { struct ifnet *xn_ifp; struct mtx sc_lock; u_int num_queues; struct netfront_rxq *rxq; struct netfront_txq *txq; u_int carrier; u_int maxfrags; device_t xbdev; uint8_t mac[ETHER_ADDR_LEN]; int xn_if_flags; struct ifmedia sc_media; bool xn_reset; }; struct netfront_rx_info { struct netif_rx_response rx; struct netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1]; }; #define XN_RX_LOCK(_q) mtx_lock(&(_q)->lock) #define XN_RX_UNLOCK(_q) mtx_unlock(&(_q)->lock) #define XN_TX_LOCK(_q) mtx_lock(&(_q)->lock) #define XN_TX_TRYLOCK(_q) mtx_trylock(&(_q)->lock) #define XN_TX_UNLOCK(_q) mtx_unlock(&(_q)->lock) #define XN_LOCK(_sc) mtx_lock(&(_sc)->sc_lock); #define XN_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_lock); #define XN_LOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_lock, MA_OWNED); #define XN_RX_LOCK_ASSERT(_q) mtx_assert(&(_q)->lock, MA_OWNED); #define XN_TX_LOCK_ASSERT(_q) mtx_assert(&(_q)->lock, MA_OWNED); #define netfront_carrier_on(netif) ((netif)->carrier = 1) #define netfront_carrier_off(netif) ((netif)->carrier = 0) #define netfront_carrier_ok(netif) ((netif)->carrier) /* Access macros for acquiring freeing slots in xn_free_{tx,rx}_idxs[]. */ static inline void add_id_to_freelist(struct mbuf **list, uintptr_t id) { KASSERT(id != 0, ("%s: the head item (0) must always be free.", __func__)); list[id] = list[0]; list[0] = (struct mbuf *)id; } static inline unsigned short get_id_from_freelist(struct mbuf **list) { uintptr_t id; id = (uintptr_t)list[0]; KASSERT(id != 0, ("%s: the head item (0) must always remain free.", __func__)); list[0] = list[id]; return (id); } static inline int xn_rxidx(RING_IDX idx) { return idx & (NET_RX_RING_SIZE - 1); } static inline struct mbuf * xn_get_rx_mbuf(struct netfront_rxq *rxq, RING_IDX ri) { int i; struct mbuf *m; i = xn_rxidx(ri); m = rxq->mbufs[i]; rxq->mbufs[i] = NULL; return (m); } static inline grant_ref_t xn_get_rx_ref(struct netfront_rxq *rxq, RING_IDX ri) { int i = xn_rxidx(ri); grant_ref_t ref = rxq->grant_ref[i]; KASSERT(ref != GRANT_REF_INVALID, ("Invalid grant reference!\n")); rxq->grant_ref[i] = GRANT_REF_INVALID; return (ref); } #define IPRINTK(fmt, args...) \ printf("[XEN] " fmt, ##args) #ifdef INVARIANTS #define WPRINTK(fmt, args...) \ printf("[XEN] " fmt, ##args) #else #define WPRINTK(fmt, args...) #endif #ifdef DEBUG #define DPRINTK(fmt, args...) \ printf("[XEN] %s: " fmt, __func__, ##args) #else #define DPRINTK(fmt, args...) #endif /** * Read the 'mac' node at the given device's node in the store, and parse that * as colon-separated octets, placing result the given mac array. mac must be * a preallocated array of length ETH_ALEN (as declared in linux/if_ether.h). * Return 0 on success, or errno on error. */ static int xen_net_read_mac(device_t dev, uint8_t mac[]) { int error, i; char *s, *e, *macstr; const char *path; path = xenbus_get_node(dev); error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); if (error == ENOENT) { /* * Deal with missing mac XenStore nodes on devices with * HVM emulation (the 'ioemu' configuration attribute) * enabled. * * The HVM emulator may execute in a stub device model * domain which lacks the permission, only given to Dom0, * to update the guest's XenStore tree. For this reason, * the HVM emulator doesn't even attempt to write the * front-side mac node, even when operating in Dom0. * However, there should always be a mac listed in the * backend tree. Fallback to this version if our query * of the front side XenStore location doesn't find * anything. */ path = xenbus_get_otherend_path(dev); error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); } if (error != 0) { xenbus_dev_fatal(dev, error, "parsing %s/mac", path); return (error); } s = macstr; for (i = 0; i < ETHER_ADDR_LEN; i++) { mac[i] = strtoul(s, &e, 16); if (s == e || (e[0] != ':' && e[0] != 0)) { free(macstr, M_XENBUS); return (ENOENT); } s = &e[1]; } free(macstr, M_XENBUS); return (0); } /** * Entry point to this code when a new device is created. Allocate the basic * structures and the ring buffers for communication with the backend, and * inform the backend of the appropriate details for those. Switch to * Connected state. */ static int netfront_probe(device_t dev) { if (xen_pv_nics_disabled()) return (ENXIO); if (!strcmp(xenbus_get_type(dev), "vif")) { device_set_desc(dev, "Virtual Network Interface"); return (0); } return (ENXIO); } static int netfront_attach(device_t dev) { int err; err = create_netdev(dev); if (err != 0) { xenbus_dev_fatal(dev, err, "creating netdev"); return (err); } SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "enable_lro", CTLFLAG_RW, &xn_enable_lro, 0, "Large Receive Offload"); SYSCTL_ADD_ULONG(device_get_sysctl_ctx(dev), SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "num_queues", CTLFLAG_RD, &xn_num_queues, "Number of pairs of queues"); return (0); } static int netfront_suspend(device_t dev) { struct netfront_info *np = device_get_softc(dev); u_int i; for (i = 0; i < np->num_queues; i++) { XN_RX_LOCK(&np->rxq[i]); XN_TX_LOCK(&np->txq[i]); } netfront_carrier_off(np); for (i = 0; i < np->num_queues; i++) { XN_RX_UNLOCK(&np->rxq[i]); XN_TX_UNLOCK(&np->txq[i]); } return (0); } /** * We are reconnecting to the backend, due to a suspend/resume, or a backend * driver restart. We tear down our netif structure and recreate it, but * leave the device-layer structures intact so that this is transparent to the * rest of the kernel. */ static int netfront_resume(device_t dev) { struct netfront_info *info = device_get_softc(dev); u_int i; if (xen_suspend_cancelled) { for (i = 0; i < info->num_queues; i++) { XN_RX_LOCK(&info->rxq[i]); XN_TX_LOCK(&info->txq[i]); } netfront_carrier_on(info); for (i = 0; i < info->num_queues; i++) { XN_RX_UNLOCK(&info->rxq[i]); XN_TX_UNLOCK(&info->txq[i]); } return (0); } netif_disconnect_backend(info); return (0); } static int write_queue_xenstore_keys(device_t dev, struct netfront_rxq *rxq, struct netfront_txq *txq, struct xs_transaction *xst, bool hierarchy) { int err; const char *message; const char *node = xenbus_get_node(dev); char *path; size_t path_size; KASSERT(rxq->id == txq->id, ("Mismatch between RX and TX queue ids")); /* Split event channel support is not yet there. */ KASSERT(rxq->xen_intr_handle == txq->xen_intr_handle, ("Split event channels are not supported")); if (hierarchy) { path_size = strlen(node) + 10; path = malloc(path_size, M_DEVBUF, M_WAITOK|M_ZERO); snprintf(path, path_size, "%s/queue-%u", node, rxq->id); } else { path_size = strlen(node) + 1; path = malloc(path_size, M_DEVBUF, M_WAITOK|M_ZERO); snprintf(path, path_size, "%s", node); } err = xs_printf(*xst, path, "tx-ring-ref","%u", txq->ring_ref); if (err != 0) { message = "writing tx ring-ref"; goto error; } err = xs_printf(*xst, path, "rx-ring-ref","%u", rxq->ring_ref); if (err != 0) { message = "writing rx ring-ref"; goto error; } err = xs_printf(*xst, path, "event-channel", "%u", xen_intr_port(rxq->xen_intr_handle)); if (err != 0) { message = "writing event-channel"; goto error; } free(path, M_DEVBUF); return (0); error: free(path, M_DEVBUF); xenbus_dev_fatal(dev, err, "%s", message); return (err); } /* Common code used when first setting up, and when resuming. */ static int talk_to_backend(device_t dev, struct netfront_info *info) { const char *message; struct xs_transaction xst; const char *node = xenbus_get_node(dev); int err; unsigned long num_queues, max_queues = 0; unsigned int i; err = xen_net_read_mac(dev, info->mac); if (err != 0) { xenbus_dev_fatal(dev, err, "parsing %s/mac", node); goto out; } err = xs_scanf(XST_NIL, xenbus_get_otherend_path(info->xbdev), "multi-queue-max-queues", NULL, "%lu", &max_queues); if (err != 0) max_queues = 1; num_queues = xn_num_queues; if (num_queues > max_queues) num_queues = max_queues; err = setup_device(dev, info, num_queues); if (err != 0) goto out; again: err = xs_transaction_start(&xst); if (err != 0) { xenbus_dev_fatal(dev, err, "starting transaction"); goto free; } if (info->num_queues == 1) { err = write_queue_xenstore_keys(dev, &info->rxq[0], &info->txq[0], &xst, false); if (err != 0) goto abort_transaction_no_def_error; } else { err = xs_printf(xst, node, "multi-queue-num-queues", "%u", info->num_queues); if (err != 0) { message = "writing multi-queue-num-queues"; goto abort_transaction; } for (i = 0; i < info->num_queues; i++) { err = write_queue_xenstore_keys(dev, &info->rxq[i], &info->txq[i], &xst, true); if (err != 0) goto abort_transaction_no_def_error; } } err = xs_printf(xst, node, "request-rx-copy", "%u", 1); if (err != 0) { message = "writing request-rx-copy"; goto abort_transaction; } err = xs_printf(xst, node, "feature-rx-notify", "%d", 1); if (err != 0) { message = "writing feature-rx-notify"; goto abort_transaction; } err = xs_printf(xst, node, "feature-sg", "%d", 1); if (err != 0) { message = "writing feature-sg"; goto abort_transaction; } if ((info->xn_ifp->if_capenable & IFCAP_LRO) != 0) { err = xs_printf(xst, node, "feature-gso-tcpv4", "%d", 1); if (err != 0) { message = "writing feature-gso-tcpv4"; goto abort_transaction; } } if ((info->xn_ifp->if_capenable & IFCAP_RXCSUM) == 0) { err = xs_printf(xst, node, "feature-no-csum-offload", "%d", 1); if (err != 0) { message = "writing feature-no-csum-offload"; goto abort_transaction; } } err = xs_transaction_end(xst, 0); if (err != 0) { if (err == EAGAIN) goto again; xenbus_dev_fatal(dev, err, "completing transaction"); goto free; } return 0; abort_transaction: xenbus_dev_fatal(dev, err, "%s", message); abort_transaction_no_def_error: xs_transaction_end(xst, 1); free: netif_free(info); out: return (err); } static void xn_rxq_intr(struct netfront_rxq *rxq) { XN_RX_LOCK(rxq); xn_rxeof(rxq); XN_RX_UNLOCK(rxq); } static void xn_txq_start(struct netfront_txq *txq) { struct netfront_info *np = txq->info; struct ifnet *ifp = np->xn_ifp; XN_TX_LOCK_ASSERT(txq); if (!drbr_empty(ifp, txq->br)) xn_txq_mq_start_locked(txq, NULL); } static void xn_txq_intr(struct netfront_txq *txq) { XN_TX_LOCK(txq); if (RING_HAS_UNCONSUMED_RESPONSES(&txq->ring)) xn_txeof(txq); xn_txq_start(txq); XN_TX_UNLOCK(txq); } static void xn_txq_tq_deferred(void *xtxq, int pending) { struct netfront_txq *txq = xtxq; XN_TX_LOCK(txq); xn_txq_start(txq); XN_TX_UNLOCK(txq); } static void disconnect_rxq(struct netfront_rxq *rxq) { xn_release_rx_bufs(rxq); gnttab_free_grant_references(rxq->gref_head); gnttab_end_foreign_access(rxq->ring_ref, NULL); /* * No split event channel support at the moment, handle will * be unbound in tx. So no need to call xen_intr_unbind here, * but we do want to reset the handler to 0. */ rxq->xen_intr_handle = 0; } static void destroy_rxq(struct netfront_rxq *rxq) { callout_drain(&rxq->rx_refill); free(rxq->ring.sring, M_DEVBUF); } static void destroy_rxqs(struct netfront_info *np) { int i; for (i = 0; i < np->num_queues; i++) destroy_rxq(&np->rxq[i]); free(np->rxq, M_DEVBUF); np->rxq = NULL; } static int setup_rxqs(device_t dev, struct netfront_info *info, unsigned long num_queues) { int q, i; int error; netif_rx_sring_t *rxs; struct netfront_rxq *rxq; info->rxq = malloc(sizeof(struct netfront_rxq) * num_queues, M_DEVBUF, M_WAITOK|M_ZERO); for (q = 0; q < num_queues; q++) { rxq = &info->rxq[q]; rxq->id = q; rxq->info = info; rxq->ring_ref = GRANT_REF_INVALID; rxq->ring.sring = NULL; snprintf(rxq->name, XN_QUEUE_NAME_LEN, "xnrx_%u", q); mtx_init(&rxq->lock, rxq->name, "netfront receive lock", MTX_DEF); for (i = 0; i <= NET_RX_RING_SIZE; i++) { rxq->mbufs[i] = NULL; rxq->grant_ref[i] = GRANT_REF_INVALID; } /* Start resources allocation */ if (gnttab_alloc_grant_references(NET_RX_RING_SIZE, &rxq->gref_head) != 0) { device_printf(dev, "allocating rx gref"); error = ENOMEM; goto fail; } rxs = (netif_rx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_WAITOK|M_ZERO); SHARED_RING_INIT(rxs); FRONT_RING_INIT(&rxq->ring, rxs, PAGE_SIZE); error = xenbus_grant_ring(dev, virt_to_mfn(rxs), &rxq->ring_ref); if (error != 0) { device_printf(dev, "granting rx ring page"); goto fail_grant_ring; } callout_init(&rxq->rx_refill, 1); } return (0); fail_grant_ring: gnttab_free_grant_references(rxq->gref_head); free(rxq->ring.sring, M_DEVBUF); fail: for (; q >= 0; q--) { disconnect_rxq(&info->rxq[q]); destroy_rxq(&info->rxq[q]); } free(info->rxq, M_DEVBUF); return (error); } static void disconnect_txq(struct netfront_txq *txq) { xn_release_tx_bufs(txq); gnttab_free_grant_references(txq->gref_head); gnttab_end_foreign_access(txq->ring_ref, NULL); xen_intr_unbind(&txq->xen_intr_handle); } static void destroy_txq(struct netfront_txq *txq) { free(txq->ring.sring, M_DEVBUF); buf_ring_free(txq->br, M_DEVBUF); taskqueue_drain_all(txq->tq); taskqueue_free(txq->tq); } static void destroy_txqs(struct netfront_info *np) { int i; for (i = 0; i < np->num_queues; i++) destroy_txq(&np->txq[i]); free(np->txq, M_DEVBUF); np->txq = NULL; } static int setup_txqs(device_t dev, struct netfront_info *info, unsigned long num_queues) { int q, i; int error; netif_tx_sring_t *txs; struct netfront_txq *txq; info->txq = malloc(sizeof(struct netfront_txq) * num_queues, M_DEVBUF, M_WAITOK|M_ZERO); for (q = 0; q < num_queues; q++) { txq = &info->txq[q]; txq->id = q; txq->info = info; txq->ring_ref = GRANT_REF_INVALID; txq->ring.sring = NULL; snprintf(txq->name, XN_QUEUE_NAME_LEN, "xntx_%u", q); mtx_init(&txq->lock, txq->name, "netfront transmit lock", MTX_DEF); for (i = 0; i <= NET_TX_RING_SIZE; i++) { txq->mbufs[i] = (void *) ((u_long) i+1); txq->grant_ref[i] = GRANT_REF_INVALID; } txq->mbufs[NET_TX_RING_SIZE] = (void *)0; /* Start resources allocation. */ if (gnttab_alloc_grant_references(NET_TX_RING_SIZE, &txq->gref_head) != 0) { device_printf(dev, "failed to allocate tx grant refs\n"); error = ENOMEM; goto fail; } txs = (netif_tx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_WAITOK|M_ZERO); SHARED_RING_INIT(txs); FRONT_RING_INIT(&txq->ring, txs, PAGE_SIZE); error = xenbus_grant_ring(dev, virt_to_mfn(txs), &txq->ring_ref); if (error != 0) { device_printf(dev, "failed to grant tx ring\n"); goto fail_grant_ring; } txq->br = buf_ring_alloc(NET_TX_RING_SIZE, M_DEVBUF, M_WAITOK, &txq->lock); TASK_INIT(&txq->defrtask, 0, xn_txq_tq_deferred, txq); txq->tq = taskqueue_create(txq->name, M_WAITOK, taskqueue_thread_enqueue, &txq->tq); error = taskqueue_start_threads(&txq->tq, 1, PI_NET, "%s txq %d", device_get_nameunit(dev), txq->id); if (error != 0) { device_printf(dev, "failed to start tx taskq %d\n", txq->id); goto fail_start_thread; } error = xen_intr_alloc_and_bind_local_port(dev, xenbus_get_otherend_id(dev), /* filter */ NULL, xn_intr, &info->txq[q], INTR_TYPE_NET | INTR_MPSAFE | INTR_ENTROPY, &txq->xen_intr_handle); if (error != 0) { device_printf(dev, "xen_intr_alloc_and_bind_local_port failed\n"); goto fail_bind_port; } } return (0); fail_bind_port: taskqueue_drain_all(txq->tq); fail_start_thread: buf_ring_free(txq->br, M_DEVBUF); taskqueue_free(txq->tq); gnttab_end_foreign_access(txq->ring_ref, NULL); fail_grant_ring: gnttab_free_grant_references(txq->gref_head); free(txq->ring.sring, M_DEVBUF); fail: for (; q >= 0; q--) { disconnect_txq(&info->txq[q]); destroy_txq(&info->txq[q]); } free(info->txq, M_DEVBUF); return (error); } static int setup_device(device_t dev, struct netfront_info *info, unsigned long num_queues) { int error; int q; if (info->txq) destroy_txqs(info); if (info->rxq) destroy_rxqs(info); info->num_queues = 0; error = setup_rxqs(dev, info, num_queues); if (error != 0) goto out; error = setup_txqs(dev, info, num_queues); if (error != 0) goto out; info->num_queues = num_queues; /* No split event channel at the moment. */ for (q = 0; q < num_queues; q++) info->rxq[q].xen_intr_handle = info->txq[q].xen_intr_handle; return (0); out: KASSERT(error != 0, ("Error path taken without providing an error code")); return (error); } #ifdef INET /** * If this interface has an ipv4 address, send an arp for it. This * helps to get the network going again after migrating hosts. */ static void netfront_send_fake_arp(device_t dev, struct netfront_info *info) { struct ifnet *ifp; struct ifaddr *ifa; ifp = info->xn_ifp; CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family == AF_INET) { arp_ifinit(ifp, ifa); } } } #endif /** * Callback received when the backend's state changes. */ static void netfront_backend_changed(device_t dev, XenbusState newstate) { struct netfront_info *sc = device_get_softc(dev); DPRINTK("newstate=%d\n", newstate); CURVNET_SET(sc->xn_ifp->if_vnet); switch (newstate) { case XenbusStateInitialising: case XenbusStateInitialised: case XenbusStateUnknown: case XenbusStateReconfigured: case XenbusStateReconfiguring: break; case XenbusStateInitWait: if (xenbus_get_state(dev) != XenbusStateInitialising) break; if (xn_connect(sc) != 0) break; /* Switch to connected state before kicking the rings. */ xenbus_set_state(sc->xbdev, XenbusStateConnected); xn_kick_rings(sc); break; case XenbusStateClosing: xenbus_set_state(dev, XenbusStateClosed); break; case XenbusStateClosed: if (sc->xn_reset) { netif_disconnect_backend(sc); xenbus_set_state(dev, XenbusStateInitialising); sc->xn_reset = false; } break; case XenbusStateConnected: #ifdef INET netfront_send_fake_arp(dev, sc); #endif break; } CURVNET_RESTORE(); } /** * \brief Verify that there is sufficient space in the Tx ring * buffer for a maximally sized request to be enqueued. * * A transmit request requires a transmit descriptor for each packet * fragment, plus up to 2 entries for "options" (e.g. TSO). */ static inline int xn_tx_slot_available(struct netfront_txq *txq) { return (RING_FREE_REQUESTS(&txq->ring) > (MAX_TX_REQ_FRAGS + 2)); } static void xn_release_tx_bufs(struct netfront_txq *txq) { int i; for (i = 1; i <= NET_TX_RING_SIZE; i++) { struct mbuf *m; m = txq->mbufs[i]; /* * We assume that no kernel addresses are * less than NET_TX_RING_SIZE. Any entry * in the table that is below this number * must be an index from free-list tracking. */ if (((uintptr_t)m) <= NET_TX_RING_SIZE) continue; gnttab_end_foreign_access_ref(txq->grant_ref[i]); gnttab_release_grant_reference(&txq->gref_head, txq->grant_ref[i]); txq->grant_ref[i] = GRANT_REF_INVALID; add_id_to_freelist(txq->mbufs, i); txq->mbufs_cnt--; if (txq->mbufs_cnt < 0) { panic("%s: tx_chain_cnt must be >= 0", __func__); } m_free(m); } } static struct mbuf * xn_alloc_one_rx_buffer(struct netfront_rxq *rxq) { struct mbuf *m; m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE); if (m == NULL) return NULL; m->m_len = m->m_pkthdr.len = MJUMPAGESIZE; return (m); } static void xn_alloc_rx_buffers(struct netfront_rxq *rxq) { RING_IDX req_prod; int notify; XN_RX_LOCK_ASSERT(rxq); if (__predict_false(rxq->info->carrier == 0)) return; for (req_prod = rxq->ring.req_prod_pvt; req_prod - rxq->ring.rsp_cons < NET_RX_RING_SIZE; req_prod++) { struct mbuf *m; unsigned short id; grant_ref_t ref; struct netif_rx_request *req; unsigned long pfn; m = xn_alloc_one_rx_buffer(rxq); if (m == NULL) break; id = xn_rxidx(req_prod); KASSERT(rxq->mbufs[id] == NULL, ("non-NULL xn_rx_chain")); rxq->mbufs[id] = m; ref = gnttab_claim_grant_reference(&rxq->gref_head); KASSERT(ref != GNTTAB_LIST_END, ("reserved grant references exhuasted")); rxq->grant_ref[id] = ref; pfn = atop(vtophys(mtod(m, vm_offset_t))); req = RING_GET_REQUEST(&rxq->ring, req_prod); gnttab_grant_foreign_access_ref(ref, xenbus_get_otherend_id(rxq->info->xbdev), pfn, 0); req->id = id; req->gref = ref; } rxq->ring.req_prod_pvt = req_prod; /* Not enough requests? Try again later. */ if (req_prod - rxq->ring.rsp_cons < NET_RX_SLOTS_MIN) { callout_reset_curcpu(&rxq->rx_refill, hz/10, xn_alloc_rx_buffers_callout, rxq); return; } wmb(); /* barrier so backend seens requests */ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&rxq->ring, notify); if (notify) xen_intr_signal(rxq->xen_intr_handle); } static void xn_alloc_rx_buffers_callout(void *arg) { struct netfront_rxq *rxq; rxq = (struct netfront_rxq *)arg; XN_RX_LOCK(rxq); xn_alloc_rx_buffers(rxq); XN_RX_UNLOCK(rxq); } static void xn_release_rx_bufs(struct netfront_rxq *rxq) { int i, ref; struct mbuf *m; for (i = 0; i < NET_RX_RING_SIZE; i++) { m = rxq->mbufs[i]; if (m == NULL) continue; ref = rxq->grant_ref[i]; if (ref == GRANT_REF_INVALID) continue; gnttab_end_foreign_access_ref(ref); gnttab_release_grant_reference(&rxq->gref_head, ref); rxq->mbufs[i] = NULL; rxq->grant_ref[i] = GRANT_REF_INVALID; m_freem(m); } } static void xn_rxeof(struct netfront_rxq *rxq) { struct ifnet *ifp; struct netfront_info *np = rxq->info; #if (defined(INET) || defined(INET6)) struct lro_ctrl *lro = &rxq->lro; #endif struct netfront_rx_info rinfo; struct netif_rx_response *rx = &rinfo.rx; struct netif_extra_info *extras = rinfo.extras; RING_IDX i, rp; struct mbuf *m; struct mbufq mbufq_rxq, mbufq_errq; int err, work_to_do; XN_RX_LOCK_ASSERT(rxq); if (!netfront_carrier_ok(np)) return; /* XXX: there should be some sane limit. */ mbufq_init(&mbufq_errq, INT_MAX); mbufq_init(&mbufq_rxq, INT_MAX); ifp = np->xn_ifp; do { rp = rxq->ring.sring->rsp_prod; rmb(); /* Ensure we see queued responses up to 'rp'. */ i = rxq->ring.rsp_cons; while ((i != rp)) { memcpy(rx, RING_GET_RESPONSE(&rxq->ring, i), sizeof(*rx)); memset(extras, 0, sizeof(rinfo.extras)); m = NULL; err = xn_get_responses(rxq, &rinfo, rp, &i, &m); if (__predict_false(err)) { if (m) (void )mbufq_enqueue(&mbufq_errq, m); if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); continue; } m->m_pkthdr.rcvif = ifp; if (rx->flags & NETRXF_data_validated) { /* * According to mbuf(9) the correct way to tell * the stack that the checksum of an inbound * packet is correct, without it actually being * present (because the underlying interface * doesn't provide it), is to set the * CSUM_DATA_VALID and CSUM_PSEUDO_HDR flags, * and the csum_data field to 0xffff. */ m->m_pkthdr.csum_flags |= (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); m->m_pkthdr.csum_data = 0xffff; } if ((rx->flags & NETRXF_extra_info) != 0 && (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type == XEN_NETIF_EXTRA_TYPE_GSO)) { m->m_pkthdr.tso_segsz = extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].u.gso.size; m->m_pkthdr.csum_flags |= CSUM_TSO; } (void )mbufq_enqueue(&mbufq_rxq, m); } rxq->ring.rsp_cons = i; xn_alloc_rx_buffers(rxq); RING_FINAL_CHECK_FOR_RESPONSES(&rxq->ring, work_to_do); } while (work_to_do); mbufq_drain(&mbufq_errq); /* * Process all the mbufs after the remapping is complete. * Break the mbuf chain first though. */ while ((m = mbufq_dequeue(&mbufq_rxq)) != NULL) { if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); #if (defined(INET) || defined(INET6)) /* Use LRO if possible */ if ((ifp->if_capenable & IFCAP_LRO) == 0 || lro->lro_cnt == 0 || tcp_lro_rx(lro, m, 0)) { /* * If LRO fails, pass up to the stack * directly. */ (*ifp->if_input)(ifp, m); } #else (*ifp->if_input)(ifp, m); #endif } #if (defined(INET) || defined(INET6)) /* * Flush any outstanding LRO work */ tcp_lro_flush_all(lro); #endif } static void xn_txeof(struct netfront_txq *txq) { RING_IDX i, prod; unsigned short id; struct ifnet *ifp; netif_tx_response_t *txr; struct mbuf *m; struct netfront_info *np = txq->info; XN_TX_LOCK_ASSERT(txq); if (!netfront_carrier_ok(np)) return; ifp = np->xn_ifp; do { prod = txq->ring.sring->rsp_prod; rmb(); /* Ensure we see responses up to 'rp'. */ for (i = txq->ring.rsp_cons; i != prod; i++) { txr = RING_GET_RESPONSE(&txq->ring, i); if (txr->status == NETIF_RSP_NULL) continue; if (txr->status != NETIF_RSP_OKAY) { printf("%s: WARNING: response is %d!\n", __func__, txr->status); } id = txr->id; m = txq->mbufs[id]; KASSERT(m != NULL, ("mbuf not found in chain")); KASSERT((uintptr_t)m > NET_TX_RING_SIZE, ("mbuf already on the free list, but we're " "trying to free it again!")); M_ASSERTVALID(m); if (__predict_false(gnttab_query_foreign_access( txq->grant_ref[id]) != 0)) { panic("%s: grant id %u still in use by the " "backend", __func__, id); } gnttab_end_foreign_access_ref(txq->grant_ref[id]); gnttab_release_grant_reference( &txq->gref_head, txq->grant_ref[id]); txq->grant_ref[id] = GRANT_REF_INVALID; txq->mbufs[id] = NULL; add_id_to_freelist(txq->mbufs, id); txq->mbufs_cnt--; m_free(m); /* Only mark the txq active if we've freed up at least one slot to try */ ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; } txq->ring.rsp_cons = prod; /* * Set a new event, then check for race with update of * tx_cons. Note that it is essential to schedule a * callback, no matter how few buffers are pending. Even if * there is space in the transmit ring, higher layers may * be blocked because too much data is outstanding: in such * cases notification from Xen is likely to be the only kick * that we'll get. */ txq->ring.sring->rsp_event = prod + ((txq->ring.sring->req_prod - prod) >> 1) + 1; mb(); } while (prod != txq->ring.sring->rsp_prod); if (txq->full && ((txq->ring.sring->req_prod - prod) < NET_TX_RING_SIZE)) { txq->full = false; xn_txq_start(txq); } } static void xn_intr(void *xsc) { struct netfront_txq *txq = xsc; struct netfront_info *np = txq->info; struct netfront_rxq *rxq = &np->rxq[txq->id]; /* kick both tx and rx */ xn_rxq_intr(rxq); xn_txq_intr(txq); } static void xn_move_rx_slot(struct netfront_rxq *rxq, struct mbuf *m, grant_ref_t ref) { int new = xn_rxidx(rxq->ring.req_prod_pvt); KASSERT(rxq->mbufs[new] == NULL, ("mbufs != NULL")); rxq->mbufs[new] = m; rxq->grant_ref[new] = ref; RING_GET_REQUEST(&rxq->ring, rxq->ring.req_prod_pvt)->id = new; RING_GET_REQUEST(&rxq->ring, rxq->ring.req_prod_pvt)->gref = ref; rxq->ring.req_prod_pvt++; } static int xn_get_extras(struct netfront_rxq *rxq, struct netif_extra_info *extras, RING_IDX rp, RING_IDX *cons) { struct netif_extra_info *extra; int err = 0; do { struct mbuf *m; grant_ref_t ref; if (__predict_false(*cons + 1 == rp)) { err = EINVAL; break; } extra = (struct netif_extra_info *) RING_GET_RESPONSE(&rxq->ring, ++(*cons)); if (__predict_false(!extra->type || extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) { err = EINVAL; } else { memcpy(&extras[extra->type - 1], extra, sizeof(*extra)); } m = xn_get_rx_mbuf(rxq, *cons); ref = xn_get_rx_ref(rxq, *cons); xn_move_rx_slot(rxq, m, ref); } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE); return err; } static int xn_get_responses(struct netfront_rxq *rxq, struct netfront_rx_info *rinfo, RING_IDX rp, RING_IDX *cons, struct mbuf **list) { struct netif_rx_response *rx = &rinfo->rx; struct netif_extra_info *extras = rinfo->extras; struct mbuf *m, *m0, *m_prev; grant_ref_t ref = xn_get_rx_ref(rxq, *cons); int frags = 1; int err = 0; u_long ret __diagused; m0 = m = m_prev = xn_get_rx_mbuf(rxq, *cons); if (rx->flags & NETRXF_extra_info) { err = xn_get_extras(rxq, extras, rp, cons); } if (m0 != NULL) { m0->m_pkthdr.len = 0; m0->m_next = NULL; } for (;;) { #if 0 DPRINTK("rx->status=%hd rx->offset=%hu frags=%u\n", rx->status, rx->offset, frags); #endif if (__predict_false(rx->status < 0 || rx->offset + rx->status > PAGE_SIZE)) { xn_move_rx_slot(rxq, m, ref); if (m0 == m) m0 = NULL; m = NULL; err = EINVAL; goto next_skip_queue; } /* * This definitely indicates a bug, either in this driver or in * the backend driver. In future this should flag the bad * situation to the system controller to reboot the backed. */ if (ref == GRANT_REF_INVALID) { printf("%s: Bad rx response id %d.\n", __func__, rx->id); err = EINVAL; goto next; } ret = gnttab_end_foreign_access_ref(ref); KASSERT(ret, ("Unable to end access to grant references")); gnttab_release_grant_reference(&rxq->gref_head, ref); next: if (m == NULL) break; m->m_len = rx->status; m->m_data += rx->offset; m0->m_pkthdr.len += rx->status; next_skip_queue: if (!(rx->flags & NETRXF_more_data)) break; if (*cons + frags == rp) { if (net_ratelimit()) WPRINTK("Need more frags\n"); err = ENOENT; printf("%s: cons %u frags %u rp %u, not enough frags\n", __func__, *cons, frags, rp); break; } /* * Note that m can be NULL, if rx->status < 0 or if * rx->offset + rx->status > PAGE_SIZE above. */ m_prev = m; rx = RING_GET_RESPONSE(&rxq->ring, *cons + frags); m = xn_get_rx_mbuf(rxq, *cons + frags); /* * m_prev == NULL can happen if rx->status < 0 or if * rx->offset + * rx->status > PAGE_SIZE above. */ if (m_prev != NULL) m_prev->m_next = m; /* * m0 can be NULL if rx->status < 0 or if * rx->offset + * rx->status > PAGE_SIZE above. */ if (m0 == NULL) m0 = m; m->m_next = NULL; ref = xn_get_rx_ref(rxq, *cons + frags); frags++; } *list = m0; *cons += frags; return (err); } /** * \brief Count the number of fragments in an mbuf chain. * * Surprisingly, there isn't an M* macro for this. */ static inline int xn_count_frags(struct mbuf *m) { int nfrags; for (nfrags = 0; m != NULL; m = m->m_next) nfrags++; return (nfrags); } /** * Given an mbuf chain, make sure we have enough room and then push * it onto the transmit ring. */ static int xn_assemble_tx_request(struct netfront_txq *txq, struct mbuf *m_head) { struct mbuf *m; struct netfront_info *np = txq->info; struct ifnet *ifp = np->xn_ifp; u_int nfrags; int otherend_id; /** * Defragment the mbuf if necessary. */ nfrags = xn_count_frags(m_head); /* * Check to see whether this request is longer than netback * can handle, and try to defrag it. */ /** * It is a bit lame, but the netback driver in Linux can't * deal with nfrags > MAX_TX_REQ_FRAGS, which is a quirk of * the Linux network stack. */ if (nfrags > np->maxfrags) { m = m_defrag(m_head, M_NOWAIT); if (!m) { /* * Defrag failed, so free the mbuf and * therefore drop the packet. */ m_freem(m_head); return (EMSGSIZE); } m_head = m; } /* Determine how many fragments now exist */ nfrags = xn_count_frags(m_head); /* * Check to see whether the defragmented packet has too many * segments for the Linux netback driver. */ /** * The FreeBSD TCP stack, with TSO enabled, can produce a chain * of mbufs longer than Linux can handle. Make sure we don't * pass a too-long chain over to the other side by dropping the * packet. It doesn't look like there is currently a way to * tell the TCP stack to generate a shorter chain of packets. */ if (nfrags > MAX_TX_REQ_FRAGS) { #ifdef DEBUG printf("%s: nfrags %d > MAX_TX_REQ_FRAGS %d, netback " "won't be able to handle it, dropping\n", __func__, nfrags, MAX_TX_REQ_FRAGS); #endif m_freem(m_head); return (EMSGSIZE); } /* * This check should be redundant. We've already verified that we * have enough slots in the ring to handle a packet of maximum * size, and that our packet is less than the maximum size. Keep * it in here as an assert for now just to make certain that * chain_cnt is accurate. */ KASSERT((txq->mbufs_cnt + nfrags) <= NET_TX_RING_SIZE, ("%s: chain_cnt (%d) + nfrags (%d) > NET_TX_RING_SIZE " "(%d)!", __func__, (int) txq->mbufs_cnt, (int) nfrags, (int) NET_TX_RING_SIZE)); /* * Start packing the mbufs in this chain into * the fragment pointers. Stop when we run out * of fragments or hit the end of the mbuf chain. */ m = m_head; otherend_id = xenbus_get_otherend_id(np->xbdev); for (m = m_head; m; m = m->m_next) { netif_tx_request_t *tx; uintptr_t id; grant_ref_t ref; u_long mfn; /* XXX Wrong type? */ tx = RING_GET_REQUEST(&txq->ring, txq->ring.req_prod_pvt); id = get_id_from_freelist(txq->mbufs); if (id == 0) panic("%s: was allocated the freelist head!\n", __func__); txq->mbufs_cnt++; if (txq->mbufs_cnt > NET_TX_RING_SIZE) panic("%s: tx_chain_cnt must be <= NET_TX_RING_SIZE\n", __func__); txq->mbufs[id] = m; tx->id = id; ref = gnttab_claim_grant_reference(&txq->gref_head); KASSERT((short)ref >= 0, ("Negative ref")); mfn = virt_to_mfn(mtod(m, vm_offset_t)); gnttab_grant_foreign_access_ref(ref, otherend_id, mfn, GNTMAP_readonly); tx->gref = txq->grant_ref[id] = ref; tx->offset = mtod(m, vm_offset_t) & (PAGE_SIZE - 1); tx->flags = 0; if (m == m_head) { /* * The first fragment has the entire packet * size, subsequent fragments have just the * fragment size. The backend works out the * true size of the first fragment by * subtracting the sizes of the other * fragments. */ tx->size = m->m_pkthdr.len; /* * The first fragment contains the checksum flags * and is optionally followed by extra data for * TSO etc. */ /** * CSUM_TSO requires checksum offloading. * Some versions of FreeBSD fail to * set CSUM_TCP in the CSUM_TSO case, * so we have to test for CSUM_TSO * explicitly. */ if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_TSO)) { tx->flags |= (NETTXF_csum_blank | NETTXF_data_validated); } if (m->m_pkthdr.csum_flags & CSUM_TSO) { struct netif_extra_info *gso = (struct netif_extra_info *) RING_GET_REQUEST(&txq->ring, ++txq->ring.req_prod_pvt); tx->flags |= NETTXF_extra_info; gso->u.gso.size = m->m_pkthdr.tso_segsz; gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4; gso->u.gso.pad = 0; gso->u.gso.features = 0; gso->type = XEN_NETIF_EXTRA_TYPE_GSO; gso->flags = 0; } } else { tx->size = m->m_len; } if (m->m_next) tx->flags |= NETTXF_more_data; txq->ring.req_prod_pvt++; } BPF_MTAP(ifp, m_head); if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); if_inc_counter(ifp, IFCOUNTER_OBYTES, m_head->m_pkthdr.len); if (m_head->m_flags & M_MCAST) if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1); xn_txeof(txq); return (0); } /* equivalent of network_open() in Linux */ static void xn_ifinit_locked(struct netfront_info *np) { struct ifnet *ifp; int i; struct netfront_rxq *rxq; XN_LOCK_ASSERT(np); ifp = np->xn_ifp; if (ifp->if_drv_flags & IFF_DRV_RUNNING || !netfront_carrier_ok(np)) return; xn_stop(np); for (i = 0; i < np->num_queues; i++) { rxq = &np->rxq[i]; XN_RX_LOCK(rxq); xn_alloc_rx_buffers(rxq); rxq->ring.sring->rsp_event = rxq->ring.rsp_cons + 1; if (RING_HAS_UNCONSUMED_RESPONSES(&rxq->ring)) xn_rxeof(rxq); XN_RX_UNLOCK(rxq); } ifp->if_drv_flags |= IFF_DRV_RUNNING; ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; if_link_state_change(ifp, LINK_STATE_UP); } static void xn_ifinit(void *xsc) { struct netfront_info *sc = xsc; XN_LOCK(sc); xn_ifinit_locked(sc); XN_UNLOCK(sc); } static int xn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) { struct netfront_info *sc = ifp->if_softc; struct ifreq *ifr = (struct ifreq *) data; device_t dev; #ifdef INET struct ifaddr *ifa = (struct ifaddr *)data; #endif int mask, error = 0, reinit; dev = sc->xbdev; switch(cmd) { case SIOCSIFADDR: #ifdef INET XN_LOCK(sc); if (ifa->ifa_addr->sa_family == AF_INET) { ifp->if_flags |= IFF_UP; if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) xn_ifinit_locked(sc); arp_ifinit(ifp, ifa); XN_UNLOCK(sc); } else { XN_UNLOCK(sc); #endif error = ether_ioctl(ifp, cmd, data); #ifdef INET } #endif break; case SIOCSIFMTU: if (ifp->if_mtu == ifr->ifr_mtu) break; ifp->if_mtu = ifr->ifr_mtu; ifp->if_drv_flags &= ~IFF_DRV_RUNNING; xn_ifinit(sc); break; case SIOCSIFFLAGS: XN_LOCK(sc); if (ifp->if_flags & IFF_UP) { /* * If only the state of the PROMISC flag changed, * then just use the 'set promisc mode' command * instead of reinitializing the entire NIC. Doing * a full re-init means reloading the firmware and * waiting for it to start up, which may take a * second or two. */ xn_ifinit_locked(sc); } else { if (ifp->if_drv_flags & IFF_DRV_RUNNING) { xn_stop(sc); } } sc->xn_if_flags = ifp->if_flags; XN_UNLOCK(sc); break; case SIOCSIFCAP: mask = ifr->ifr_reqcap ^ ifp->if_capenable; reinit = 0; if (mask & IFCAP_TXCSUM) { ifp->if_capenable ^= IFCAP_TXCSUM; ifp->if_hwassist ^= XN_CSUM_FEATURES; } if (mask & IFCAP_TSO4) { ifp->if_capenable ^= IFCAP_TSO4; ifp->if_hwassist ^= CSUM_TSO; } if (mask & (IFCAP_RXCSUM | IFCAP_LRO)) { /* These Rx features require us to renegotiate. */ reinit = 1; if (mask & IFCAP_RXCSUM) ifp->if_capenable ^= IFCAP_RXCSUM; if (mask & IFCAP_LRO) ifp->if_capenable ^= IFCAP_LRO; } if (reinit == 0) break; /* * We must reset the interface so the backend picks up the * new features. */ device_printf(sc->xbdev, "performing interface reset due to feature change\n"); XN_LOCK(sc); netfront_carrier_off(sc); sc->xn_reset = true; /* * NB: the pending packet queue is not flushed, since * the interface should still support the old options. */ XN_UNLOCK(sc); /* * Delete the xenstore nodes that export features. * * NB: There's a xenbus state called * "XenbusStateReconfiguring", which is what we should set * here. Sadly none of the backends know how to handle it, * and simply disconnect from the frontend, so we will just * switch back to XenbusStateInitialising in order to force * a reconnection. */ xs_rm(XST_NIL, xenbus_get_node(dev), "feature-gso-tcpv4"); xs_rm(XST_NIL, xenbus_get_node(dev), "feature-no-csum-offload"); xenbus_set_state(dev, XenbusStateClosing); /* * Wait for the frontend to reconnect before returning * from the ioctl. 30s should be more than enough for any * sane backend to reconnect. */ error = tsleep(sc, 0, "xn_rst", 30*hz); break; case SIOCADDMULTI: case SIOCDELMULTI: break; case SIOCSIFMEDIA: case SIOCGIFMEDIA: error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd); break; default: error = ether_ioctl(ifp, cmd, data); } return (error); } static void xn_stop(struct netfront_info *sc) { struct ifnet *ifp; XN_LOCK_ASSERT(sc); ifp = sc->xn_ifp; ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE); if_link_state_change(ifp, LINK_STATE_DOWN); } static void xn_rebuild_rx_bufs(struct netfront_rxq *rxq) { int requeue_idx, i; grant_ref_t ref; netif_rx_request_t *req; for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) { struct mbuf *m; u_long pfn; if (rxq->mbufs[i] == NULL) continue; m = rxq->mbufs[requeue_idx] = xn_get_rx_mbuf(rxq, i); ref = rxq->grant_ref[requeue_idx] = xn_get_rx_ref(rxq, i); req = RING_GET_REQUEST(&rxq->ring, requeue_idx); pfn = vtophys(mtod(m, vm_offset_t)) >> PAGE_SHIFT; gnttab_grant_foreign_access_ref(ref, xenbus_get_otherend_id(rxq->info->xbdev), pfn, 0); req->gref = ref; req->id = requeue_idx; requeue_idx++; } rxq->ring.req_prod_pvt = requeue_idx; } /* START of Xenolinux helper functions adapted to FreeBSD */ static int xn_connect(struct netfront_info *np) { int i, error; u_int feature_rx_copy; struct netfront_rxq *rxq; struct netfront_txq *txq; error = xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), "feature-rx-copy", NULL, "%u", &feature_rx_copy); if (error != 0) feature_rx_copy = 0; /* We only support rx copy. */ if (!feature_rx_copy) return (EPROTONOSUPPORT); /* Recovery procedure: */ error = talk_to_backend(np->xbdev, np); if (error != 0) return (error); /* Step 1: Reinitialise variables. */ xn_query_features(np); xn_configure_features(np); /* Step 2: Release TX buffer */ for (i = 0; i < np->num_queues; i++) { txq = &np->txq[i]; xn_release_tx_bufs(txq); } /* Step 3: Rebuild the RX buffer freelist and the RX ring itself. */ for (i = 0; i < np->num_queues; i++) { rxq = &np->rxq[i]; xn_rebuild_rx_bufs(rxq); } /* Step 4: All public and private state should now be sane. Get * ready to start sending and receiving packets and give the driver * domain a kick because we've probably just requeued some * packets. */ netfront_carrier_on(np); wakeup(np); return (0); } static void xn_kick_rings(struct netfront_info *np) { struct netfront_rxq *rxq; struct netfront_txq *txq; int i; for (i = 0; i < np->num_queues; i++) { txq = &np->txq[i]; rxq = &np->rxq[i]; xen_intr_signal(txq->xen_intr_handle); XN_TX_LOCK(txq); xn_txeof(txq); XN_TX_UNLOCK(txq); XN_RX_LOCK(rxq); xn_alloc_rx_buffers(rxq); XN_RX_UNLOCK(rxq); } } static void xn_query_features(struct netfront_info *np) { int val; device_printf(np->xbdev, "backend features:"); if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), "feature-sg", NULL, "%d", &val) != 0) val = 0; np->maxfrags = 1; if (val) { np->maxfrags = MAX_TX_REQ_FRAGS; printf(" feature-sg"); } if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), "feature-gso-tcpv4", NULL, "%d", &val) != 0) val = 0; np->xn_ifp->if_capabilities &= ~(IFCAP_TSO4|IFCAP_LRO); if (val) { np->xn_ifp->if_capabilities |= IFCAP_TSO4|IFCAP_LRO; printf(" feature-gso-tcp4"); } /* * HW CSUM offload is assumed to be available unless * feature-no-csum-offload is set in xenstore. */ if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), "feature-no-csum-offload", NULL, "%d", &val) != 0) val = 0; np->xn_ifp->if_capabilities |= IFCAP_HWCSUM; if (val) { np->xn_ifp->if_capabilities &= ~(IFCAP_HWCSUM); printf(" feature-no-csum-offload"); } printf("\n"); } static int xn_configure_features(struct netfront_info *np) { int err, cap_enabled; #if (defined(INET) || defined(INET6)) int i; #endif struct ifnet *ifp; ifp = np->xn_ifp; err = 0; if ((ifp->if_capenable & ifp->if_capabilities) == ifp->if_capenable) { /* Current options are available, no need to do anything. */ return (0); } /* Try to preserve as many options as possible. */ cap_enabled = ifp->if_capenable; ifp->if_capenable = ifp->if_hwassist = 0; #if (defined(INET) || defined(INET6)) if ((cap_enabled & IFCAP_LRO) != 0) for (i = 0; i < np->num_queues; i++) tcp_lro_free(&np->rxq[i].lro); if (xn_enable_lro && (ifp->if_capabilities & cap_enabled & IFCAP_LRO) != 0) { ifp->if_capenable |= IFCAP_LRO; for (i = 0; i < np->num_queues; i++) { err = tcp_lro_init(&np->rxq[i].lro); if (err != 0) { device_printf(np->xbdev, "LRO initialization failed\n"); ifp->if_capenable &= ~IFCAP_LRO; break; } np->rxq[i].lro.ifp = ifp; } } if ((ifp->if_capabilities & cap_enabled & IFCAP_TSO4) != 0) { ifp->if_capenable |= IFCAP_TSO4; ifp->if_hwassist |= CSUM_TSO; } #endif if ((ifp->if_capabilities & cap_enabled & IFCAP_TXCSUM) != 0) { ifp->if_capenable |= IFCAP_TXCSUM; ifp->if_hwassist |= XN_CSUM_FEATURES; } if ((ifp->if_capabilities & cap_enabled & IFCAP_RXCSUM) != 0) ifp->if_capenable |= IFCAP_RXCSUM; return (err); } static int xn_txq_mq_start_locked(struct netfront_txq *txq, struct mbuf *m) { struct netfront_info *np; struct ifnet *ifp; struct buf_ring *br; int error, notify; np = txq->info; br = txq->br; ifp = np->xn_ifp; error = 0; XN_TX_LOCK_ASSERT(txq); if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || !netfront_carrier_ok(np)) { if (m != NULL) error = drbr_enqueue(ifp, br, m); return (error); } if (m != NULL) { error = drbr_enqueue(ifp, br, m); if (error != 0) return (error); } while ((m = drbr_peek(ifp, br)) != NULL) { if (!xn_tx_slot_available(txq)) { drbr_putback(ifp, br, m); break; } error = xn_assemble_tx_request(txq, m); /* xn_assemble_tx_request always consumes the mbuf*/ if (error != 0) { drbr_advance(ifp, br); break; } RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&txq->ring, notify); if (notify) xen_intr_signal(txq->xen_intr_handle); drbr_advance(ifp, br); } if (RING_FULL(&txq->ring)) txq->full = true; return (0); } static int xn_txq_mq_start(struct ifnet *ifp, struct mbuf *m) { struct netfront_info *np; struct netfront_txq *txq; int i, npairs, error; np = ifp->if_softc; npairs = np->num_queues; if (!netfront_carrier_ok(np)) return (ENOBUFS); KASSERT(npairs != 0, ("called with 0 available queues")); /* check if flowid is set */ if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) i = m->m_pkthdr.flowid % npairs; else i = curcpu % npairs; txq = &np->txq[i]; if (XN_TX_TRYLOCK(txq) != 0) { error = xn_txq_mq_start_locked(txq, m); XN_TX_UNLOCK(txq); } else { error = drbr_enqueue(ifp, txq->br, m); taskqueue_enqueue(txq->tq, &txq->defrtask); } return (error); } static void xn_qflush(struct ifnet *ifp) { struct netfront_info *np; struct netfront_txq *txq; struct mbuf *m; int i; np = ifp->if_softc; for (i = 0; i < np->num_queues; i++) { txq = &np->txq[i]; XN_TX_LOCK(txq); while ((m = buf_ring_dequeue_sc(txq->br)) != NULL) m_freem(m); XN_TX_UNLOCK(txq); } if_qflush(ifp); } /** * Create a network device. * @param dev Newbus device representing this virtual NIC. */ int create_netdev(device_t dev) { struct netfront_info *np; int err; struct ifnet *ifp; np = device_get_softc(dev); np->xbdev = dev; mtx_init(&np->sc_lock, "xnsc", "netfront softc lock", MTX_DEF); ifmedia_init(&np->sc_media, 0, xn_ifmedia_upd, xn_ifmedia_sts); ifmedia_add(&np->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL); ifmedia_set(&np->sc_media, IFM_ETHER|IFM_MANUAL); err = xen_net_read_mac(dev, np->mac); if (err != 0) goto error; /* Set up ifnet structure */ ifp = np->xn_ifp = if_alloc(IFT_ETHER); ifp->if_softc = np; if_initname(ifp, "xn", device_get_unit(dev)); ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; ifp->if_ioctl = xn_ioctl; ifp->if_transmit = xn_txq_mq_start; ifp->if_qflush = xn_qflush; ifp->if_init = xn_ifinit; ifp->if_hwassist = XN_CSUM_FEATURES; /* Enable all supported features at device creation. */ ifp->if_capenable = ifp->if_capabilities = IFCAP_HWCSUM|IFCAP_TSO4|IFCAP_LRO; ifp->if_hw_tsomax = 65536 - (ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN); ifp->if_hw_tsomaxsegcount = MAX_TX_REQ_FRAGS; ifp->if_hw_tsomaxsegsize = PAGE_SIZE; ether_ifattach(ifp, np->mac); netfront_carrier_off(np); return (0); error: KASSERT(err != 0, ("Error path with no error code specified")); return (err); } static int netfront_detach(device_t dev) { struct netfront_info *info = device_get_softc(dev); DPRINTK("%s\n", xenbus_get_node(dev)); netif_free(info); return 0; } static void netif_free(struct netfront_info *np) { XN_LOCK(np); xn_stop(np); XN_UNLOCK(np); netif_disconnect_backend(np); ether_ifdetach(np->xn_ifp); free(np->rxq, M_DEVBUF); free(np->txq, M_DEVBUF); if_free(np->xn_ifp); np->xn_ifp = NULL; ifmedia_removeall(&np->sc_media); } static void netif_disconnect_backend(struct netfront_info *np) { u_int i; for (i = 0; i < np->num_queues; i++) { XN_RX_LOCK(&np->rxq[i]); XN_TX_LOCK(&np->txq[i]); } netfront_carrier_off(np); for (i = 0; i < np->num_queues; i++) { XN_RX_UNLOCK(&np->rxq[i]); XN_TX_UNLOCK(&np->txq[i]); } for (i = 0; i < np->num_queues; i++) { disconnect_rxq(&np->rxq[i]); disconnect_txq(&np->txq[i]); } } static int xn_ifmedia_upd(struct ifnet *ifp) { return (0); } static void xn_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr) { ifmr->ifm_status = IFM_AVALID|IFM_ACTIVE; ifmr->ifm_active = IFM_ETHER|IFM_MANUAL; } /* ** Driver registration ** */ static device_method_t netfront_methods[] = { /* Device interface */ DEVMETHOD(device_probe, netfront_probe), DEVMETHOD(device_attach, netfront_attach), DEVMETHOD(device_detach, netfront_detach), DEVMETHOD(device_shutdown, bus_generic_shutdown), DEVMETHOD(device_suspend, netfront_suspend), DEVMETHOD(device_resume, netfront_resume), /* Xenbus interface */ DEVMETHOD(xenbus_otherend_changed, netfront_backend_changed), DEVMETHOD_END }; static driver_t netfront_driver = { "xn", netfront_methods, sizeof(struct netfront_info), }; devclass_t netfront_devclass; DRIVER_MODULE(xe, xenbusb_front, netfront_driver, netfront_devclass, NULL, NULL);