/* * Copyright (C) 2011-2012 Matteo Landi, Luigi Rizzo. 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. */ #define NM_BRIDGE /* * This module supports memory mapped access to network devices, * see netmap(4). * * The module uses a large, memory pool allocated by the kernel * and accessible as mmapped memory by multiple userspace threads/processes. * The memory pool contains packet buffers and "netmap rings", * i.e. user-accessible copies of the interface's queues. * * Access to the network card works like this: * 1. a process/thread issues one or more open() on /dev/netmap, to create * select()able file descriptor on which events are reported. * 2. on each descriptor, the process issues an ioctl() to identify * the interface that should report events to the file descriptor. * 3. on each descriptor, the process issues an mmap() request to * map the shared memory region within the process' address space. * The list of interesting queues is indicated by a location in * the shared memory region. * 4. using the functions in the netmap(4) userspace API, a process * can look up the occupation state of a queue, access memory buffers, * and retrieve received packets or enqueue packets to transmit. * 5. using some ioctl()s the process can synchronize the userspace view * of the queue with the actual status in the kernel. This includes both * receiving the notification of new packets, and transmitting new * packets on the output interface. * 6. select() or poll() can be used to wait for events on individual * transmit or receive queues (or all queues for a given interface). */ #ifdef linux #include "bsd_glue.h" static netdev_tx_t linux_netmap_start(struct sk_buff *skb, struct net_device *dev); #endif /* linux */ #ifdef __APPLE__ #include "osx_glue.h" #endif /* __APPLE__ */ #ifdef __FreeBSD__ #include /* prerequisite */ __FBSDID("$FreeBSD$"); #include #include #include #include /* defines used in kernel.h */ #include #include /* types used in module initialization */ #include /* cdevsw struct */ #include /* uio struct */ #include #include /* struct socket */ #include #include /* PROT_EXEC */ #include #include #include /* vtophys */ #include /* vtophys */ #include /* sockaddrs */ #include #include #include #include #include /* BIOCIMMEDIATE */ #include #include /* bus_dmamap_* */ MALLOC_DEFINE(M_NETMAP, "netmap", "Network memory map"); #endif /* __FreeBSD__ */ #include #include u_int netmap_total_buffers; u_int netmap_buf_size; char *netmap_buffer_base; /* address of an invalid buffer */ /* user-controlled variables */ int netmap_verbose; static int netmap_no_timestamp; /* don't timestamp on rxsync */ SYSCTL_NODE(_dev, OID_AUTO, netmap, CTLFLAG_RW, 0, "Netmap args"); SYSCTL_INT(_dev_netmap, OID_AUTO, verbose, CTLFLAG_RW, &netmap_verbose, 0, "Verbose mode"); SYSCTL_INT(_dev_netmap, OID_AUTO, no_timestamp, CTLFLAG_RW, &netmap_no_timestamp, 0, "no_timestamp"); int netmap_mitigate = 1; SYSCTL_INT(_dev_netmap, OID_AUTO, mitigate, CTLFLAG_RW, &netmap_mitigate, 0, ""); int netmap_no_pendintr = 1; SYSCTL_INT(_dev_netmap, OID_AUTO, no_pendintr, CTLFLAG_RW, &netmap_no_pendintr, 0, "Always look for new received packets."); int netmap_drop = 0; /* debugging */ int netmap_flags = 0; /* debug flags */ int netmap_copy = 0; /* debugging, copy content */ SYSCTL_INT(_dev_netmap, OID_AUTO, drop, CTLFLAG_RW, &netmap_drop, 0 , ""); SYSCTL_INT(_dev_netmap, OID_AUTO, flags, CTLFLAG_RW, &netmap_flags, 0 , ""); SYSCTL_INT(_dev_netmap, OID_AUTO, copy, CTLFLAG_RW, &netmap_copy, 0 , ""); #ifdef NM_BRIDGE /* support for netmap bridge */ /* * system parameters. * * All switched ports have prefix NM_NAME. * The switch has a max of NM_BDG_MAXPORTS ports (often stored in a bitmap, * so a practical upper bound is 64). * Each tx ring is read-write, whereas rx rings are readonly (XXX not done yet). * The virtual interfaces use per-queue lock instead of core lock. * In the tx loop, we aggregate traffic in batches to make all operations * faster. The batch size is NM_BDG_BATCH */ #define NM_NAME "vale" /* prefix for the interface */ #define NM_BDG_MAXPORTS 16 /* up to 64 ? */ #define NM_BRIDGE_RINGSIZE 1024 /* in the device */ #define NM_BDG_HASH 1024 /* forwarding table entries */ #define NM_BDG_BATCH 1024 /* entries in the forwarding buffer */ #define NM_BRIDGES 4 /* number of bridges */ int netmap_bridge = NM_BDG_BATCH; /* bridge batch size */ SYSCTL_INT(_dev_netmap, OID_AUTO, bridge, CTLFLAG_RW, &netmap_bridge, 0 , ""); #ifdef linux #define ADD_BDG_REF(ifp) (NA(ifp)->if_refcount++) #define DROP_BDG_REF(ifp) (NA(ifp)->if_refcount-- <= 1) #else /* !linux */ #define ADD_BDG_REF(ifp) (ifp)->if_refcount++ #define DROP_BDG_REF(ifp) refcount_release(&(ifp)->if_refcount) #ifdef __FreeBSD__ #include #include #endif /* __FreeBSD__ */ #define prefetch(x) __builtin_prefetch(x) #endif /* !linux */ static void bdg_netmap_attach(struct ifnet *ifp); static int bdg_netmap_reg(struct ifnet *ifp, int onoff); /* per-tx-queue entry */ struct nm_bdg_fwd { /* forwarding entry for a bridge */ void *buf; uint64_t dst; /* dst mask */ uint32_t src; /* src index ? */ uint16_t len; /* src len */ }; struct nm_hash_ent { uint64_t mac; /* the top 2 bytes are the epoch */ uint64_t ports; }; /* * Interfaces for a bridge are all in ports[]. * The array has fixed size, an empty entry does not terminate * the search. */ struct nm_bridge { struct ifnet *bdg_ports[NM_BDG_MAXPORTS]; int n_ports; uint64_t act_ports; int freelist; /* first buffer index */ NM_SELINFO_T si; /* poll/select wait queue */ NM_LOCK_T bdg_lock; /* protect the selinfo ? */ /* the forwarding table, MAC+ports */ struct nm_hash_ent ht[NM_BDG_HASH]; int namelen; /* 0 means free */ char basename[IFNAMSIZ]; }; struct nm_bridge nm_bridges[NM_BRIDGES]; #define BDG_LOCK(b) mtx_lock(&(b)->bdg_lock) #define BDG_UNLOCK(b) mtx_unlock(&(b)->bdg_lock) /* * NA(ifp)->bdg_port port index */ // XXX only for multiples of 64 bytes, non overlapped. static inline void pkt_copy(void *_src, void *_dst, int l) { uint64_t *src = _src; uint64_t *dst = _dst; if (unlikely(l >= 1024)) { bcopy(src, dst, l); return; } for (; likely(l > 0); l-=64) { *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; *dst++ = *src++; } } /* * locate a bridge among the existing ones. * a ':' in the name terminates the bridge name. Otherwise, just NM_NAME. * We assume that this is called with a name of at least NM_NAME chars. */ static struct nm_bridge * nm_find_bridge(const char *name) { int i, l, namelen, e; struct nm_bridge *b = NULL; namelen = strlen(NM_NAME); /* base length */ l = strlen(name); /* actual length */ for (i = namelen + 1; i < l; i++) { if (name[i] == ':') { namelen = i; break; } } if (namelen >= IFNAMSIZ) namelen = IFNAMSIZ; ND("--- prefix is '%.*s' ---", namelen, name); /* use the first entry for locking */ BDG_LOCK(nm_bridges); // XXX do better for (e = -1, i = 1; i < NM_BRIDGES; i++) { b = nm_bridges + i; if (b->namelen == 0) e = i; /* record empty slot */ else if (strncmp(name, b->basename, namelen) == 0) { ND("found '%.*s' at %d", namelen, name, i); break; } } if (i == NM_BRIDGES) { /* all full */ if (e == -1) { /* no empty slot */ b = NULL; } else { b = nm_bridges + e; strncpy(b->basename, name, namelen); b->namelen = namelen; } } BDG_UNLOCK(nm_bridges); return b; } #endif /* NM_BRIDGE */ /* * Fetch configuration from the device, to cope with dynamic * reconfigurations after loading the module. */ static int netmap_update_config(struct netmap_adapter *na) { struct ifnet *ifp = na->ifp; u_int txr, txd, rxr, rxd; txr = txd = rxr = rxd = 0; if (na->nm_config) { na->nm_config(ifp, &txr, &txd, &rxr, &rxd); } else { /* take whatever we had at init time */ txr = na->num_tx_rings; txd = na->num_tx_desc; rxr = na->num_rx_rings; rxd = na->num_rx_desc; } if (na->num_tx_rings == txr && na->num_tx_desc == txd && na->num_rx_rings == rxr && na->num_rx_desc == rxd) return 0; /* nothing changed */ if (netmap_verbose || na->refcount > 0) { D("stored config %s: txring %d x %d, rxring %d x %d", ifp->if_xname, na->num_tx_rings, na->num_tx_desc, na->num_rx_rings, na->num_rx_desc); D("new config %s: txring %d x %d, rxring %d x %d", ifp->if_xname, txr, txd, rxr, rxd); } if (na->refcount == 0) { D("configuration changed (but fine)"); na->num_tx_rings = txr; na->num_tx_desc = txd; na->num_rx_rings = rxr; na->num_rx_desc = rxd; return 0; } D("configuration changed while active, this is bad..."); return 1; } /*------------- memory allocator -----------------*/ #ifdef NETMAP_MEM2 #include "netmap_mem2.c" #else /* !NETMAP_MEM2 */ #include "netmap_mem1.c" #endif /* !NETMAP_MEM2 */ /*------------ end of memory allocator ----------*/ /* Structure associated to each thread which registered an interface. * * The first 4 fields of this structure are written by NIOCREGIF and * read by poll() and NIOC?XSYNC. * There is low contention among writers (actually, a correct user program * should have no contention among writers) and among writers and readers, * so we use a single global lock to protect the structure initialization. * Since initialization involves the allocation of memory, we reuse the memory * allocator lock. * Read access to the structure is lock free. Readers must check that * np_nifp is not NULL before using the other fields. * If np_nifp is NULL initialization has not been performed, so they should * return an error to userlevel. * * The ref_done field is used to regulate access to the refcount in the * memory allocator. The refcount must be incremented at most once for * each open("/dev/netmap"). The increment is performed by the first * function that calls netmap_get_memory() (currently called by * mmap(), NIOCGINFO and NIOCREGIF). * If the refcount is incremented, it is then decremented when the * private structure is destroyed. */ struct netmap_priv_d { struct netmap_if * volatile np_nifp; /* netmap interface descriptor. */ struct ifnet *np_ifp; /* device for which we hold a reference */ int np_ringid; /* from the ioctl */ u_int np_qfirst, np_qlast; /* range of rings to scan */ uint16_t np_txpoll; unsigned long ref_done; /* use with NMA_LOCK held */ }; static int netmap_get_memory(struct netmap_priv_d* p) { int error = 0; NMA_LOCK(); if (!p->ref_done) { error = netmap_memory_finalize(); if (!error) p->ref_done = 1; } NMA_UNLOCK(); return error; } /* * File descriptor's private data destructor. * * Call nm_register(ifp,0) to stop netmap mode on the interface and * revert to normal operation. We expect that np_ifp has not gone. */ /* call with NMA_LOCK held */ static void netmap_dtor_locked(void *data) { struct netmap_priv_d *priv = data; struct ifnet *ifp = priv->np_ifp; struct netmap_adapter *na = NA(ifp); struct netmap_if *nifp = priv->np_nifp; na->refcount--; if (na->refcount <= 0) { /* last instance */ u_int i, j, lim; if (netmap_verbose) D("deleting last instance for %s", ifp->if_xname); /* * there is a race here with *_netmap_task() and * netmap_poll(), which don't run under NETMAP_REG_LOCK. * na->refcount == 0 && na->ifp->if_capenable & IFCAP_NETMAP * (aka NETMAP_DELETING(na)) are a unique marker that the * device is dying. * Before destroying stuff we sleep a bit, and then complete * the job. NIOCREG should realize the condition and * loop until they can continue; the other routines * should check the condition at entry and quit if * they cannot run. */ na->nm_lock(ifp, NETMAP_REG_UNLOCK, 0); tsleep(na, 0, "NIOCUNREG", 4); na->nm_lock(ifp, NETMAP_REG_LOCK, 0); na->nm_register(ifp, 0); /* off, clear IFCAP_NETMAP */ /* Wake up any sleeping threads. netmap_poll will * then return POLLERR */ for (i = 0; i < na->num_tx_rings + 1; i++) selwakeuppri(&na->tx_rings[i].si, PI_NET); for (i = 0; i < na->num_rx_rings + 1; i++) selwakeuppri(&na->rx_rings[i].si, PI_NET); selwakeuppri(&na->tx_si, PI_NET); selwakeuppri(&na->rx_si, PI_NET); /* release all buffers */ for (i = 0; i < na->num_tx_rings + 1; i++) { struct netmap_ring *ring = na->tx_rings[i].ring; lim = na->tx_rings[i].nkr_num_slots; for (j = 0; j < lim; j++) netmap_free_buf(nifp, ring->slot[j].buf_idx); /* knlist_destroy(&na->tx_rings[i].si.si_note); */ mtx_destroy(&na->tx_rings[i].q_lock); } for (i = 0; i < na->num_rx_rings + 1; i++) { struct netmap_ring *ring = na->rx_rings[i].ring; lim = na->rx_rings[i].nkr_num_slots; for (j = 0; j < lim; j++) netmap_free_buf(nifp, ring->slot[j].buf_idx); /* knlist_destroy(&na->rx_rings[i].si.si_note); */ mtx_destroy(&na->rx_rings[i].q_lock); } /* XXX kqueue(9) needed; these will mirror knlist_init. */ /* knlist_destroy(&na->tx_si.si_note); */ /* knlist_destroy(&na->rx_si.si_note); */ netmap_free_rings(na); wakeup(na); } netmap_if_free(nifp); } static void nm_if_rele(struct ifnet *ifp) { #ifndef NM_BRIDGE if_rele(ifp); #else /* NM_BRIDGE */ int i, full; struct nm_bridge *b; if (strncmp(ifp->if_xname, NM_NAME, sizeof(NM_NAME) - 1)) { if_rele(ifp); return; } if (!DROP_BDG_REF(ifp)) return; b = ifp->if_bridge; BDG_LOCK(nm_bridges); BDG_LOCK(b); ND("want to disconnect %s from the bridge", ifp->if_xname); full = 0; for (i = 0; i < NM_BDG_MAXPORTS; i++) { if (b->bdg_ports[i] == ifp) { b->bdg_ports[i] = NULL; bzero(ifp, sizeof(*ifp)); free(ifp, M_DEVBUF); break; } else if (b->bdg_ports[i] != NULL) full = 1; } BDG_UNLOCK(b); if (full == 0) { ND("freeing bridge %d", b - nm_bridges); b->namelen = 0; } BDG_UNLOCK(nm_bridges); if (i == NM_BDG_MAXPORTS) D("ouch, cannot find ifp to remove"); #endif /* NM_BRIDGE */ } static void netmap_dtor(void *data) { struct netmap_priv_d *priv = data; struct ifnet *ifp = priv->np_ifp; struct netmap_adapter *na; NMA_LOCK(); if (ifp) { na = NA(ifp); na->nm_lock(ifp, NETMAP_REG_LOCK, 0); netmap_dtor_locked(data); na->nm_lock(ifp, NETMAP_REG_UNLOCK, 0); nm_if_rele(ifp); } if (priv->ref_done) { netmap_memory_deref(); } NMA_UNLOCK(); bzero(priv, sizeof(*priv)); /* XXX for safety */ free(priv, M_DEVBUF); } #ifdef __FreeBSD__ #include #include #include #include #include #include static struct cdev_pager_ops saved_cdev_pager_ops; static int netmap_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred, u_short *color) { if (netmap_verbose) D("first mmap for %p", handle); return saved_cdev_pager_ops.cdev_pg_ctor(handle, size, prot, foff, cred, color); } static void netmap_dev_pager_dtor(void *handle) { saved_cdev_pager_ops.cdev_pg_dtor(handle); ND("ready to release memory for %p", handle); } static struct cdev_pager_ops netmap_cdev_pager_ops = { .cdev_pg_ctor = netmap_dev_pager_ctor, .cdev_pg_dtor = netmap_dev_pager_dtor, .cdev_pg_fault = NULL, }; static int netmap_mmap_single(struct cdev *cdev, vm_ooffset_t *foff, vm_size_t objsize, vm_object_t *objp, int prot) { vm_object_t obj; ND("cdev %p foff %jd size %jd objp %p prot %d", cdev, (intmax_t )*foff, (intmax_t )objsize, objp, prot); obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, curthread->td_ucred); ND("returns obj %p", obj); if (obj == NULL) return EINVAL; if (saved_cdev_pager_ops.cdev_pg_fault == NULL) { ND("initialize cdev_pager_ops"); saved_cdev_pager_ops = *(obj->un_pager.devp.ops); netmap_cdev_pager_ops.cdev_pg_fault = saved_cdev_pager_ops.cdev_pg_fault; }; obj->un_pager.devp.ops = &netmap_cdev_pager_ops; *objp = obj; return 0; } #endif /* __FreeBSD__ */ /* * mmap(2) support for the "netmap" device. * * Expose all the memory previously allocated by our custom memory * allocator: this way the user has only to issue a single mmap(2), and * can work on all the data structures flawlessly. * * Return 0 on success, -1 otherwise. */ #ifdef __FreeBSD__ static int netmap_mmap(__unused struct cdev *dev, #if __FreeBSD_version < 900000 vm_offset_t offset, vm_paddr_t *paddr, int nprot #else vm_ooffset_t offset, vm_paddr_t *paddr, int nprot, __unused vm_memattr_t *memattr #endif ) { int error = 0; struct netmap_priv_d *priv; if (nprot & PROT_EXEC) return (-1); // XXX -1 or EINVAL ? error = devfs_get_cdevpriv((void **)&priv); if (error == EBADF) { /* called on fault, memory is initialized */ ND(5, "handling fault at ofs 0x%x", offset); error = 0; } else if (error == 0) /* make sure memory is set */ error = netmap_get_memory(priv); if (error) return (error); ND("request for offset 0x%x", (uint32_t)offset); *paddr = netmap_ofstophys(offset); return (*paddr ? 0 : ENOMEM); } static int netmap_close(struct cdev *dev, int fflag, int devtype, struct thread *td) { if (netmap_verbose) D("dev %p fflag 0x%x devtype %d td %p", dev, fflag, devtype, td); return 0; } static int netmap_open(struct cdev *dev, int oflags, int devtype, struct thread *td) { struct netmap_priv_d *priv; int error; priv = malloc(sizeof(struct netmap_priv_d), M_DEVBUF, M_NOWAIT | M_ZERO); if (priv == NULL) return ENOMEM; error = devfs_set_cdevpriv(priv, netmap_dtor); if (error) return error; return 0; } #endif /* __FreeBSD__ */ /* * Handlers for synchronization of the queues from/to the host. * * netmap_sync_to_host() passes packets up. We are called from a * system call in user process context, and the only contention * can be among multiple user threads erroneously calling * this routine concurrently. In principle we should not even * need to lock. */ static void netmap_sync_to_host(struct netmap_adapter *na) { struct netmap_kring *kring = &na->tx_rings[na->num_tx_rings]; struct netmap_ring *ring = kring->ring; struct mbuf *head = NULL, *tail = NULL, *m; u_int k, n, lim = kring->nkr_num_slots - 1; k = ring->cur; if (k > lim) { netmap_ring_reinit(kring); return; } // na->nm_lock(na->ifp, NETMAP_CORE_LOCK, 0); /* Take packets from hwcur to cur and pass them up. * In case of no buffers we give up. At the end of the loop, * the queue is drained in all cases. */ for (n = kring->nr_hwcur; n != k;) { struct netmap_slot *slot = &ring->slot[n]; n = (n == lim) ? 0 : n + 1; if (slot->len < 14 || slot->len > NETMAP_BUF_SIZE) { D("bad pkt at %d len %d", n, slot->len); continue; } m = m_devget(NMB(slot), slot->len, 0, na->ifp, NULL); if (m == NULL) break; if (tail) tail->m_nextpkt = m; else head = m; tail = m; m->m_nextpkt = NULL; } kring->nr_hwcur = k; kring->nr_hwavail = ring->avail = lim; // na->nm_lock(na->ifp, NETMAP_CORE_UNLOCK, 0); /* send packets up, outside the lock */ while ((m = head) != NULL) { head = head->m_nextpkt; m->m_nextpkt = NULL; if (netmap_verbose & NM_VERB_HOST) D("sending up pkt %p size %d", m, MBUF_LEN(m)); NM_SEND_UP(na->ifp, m); } } /* * rxsync backend for packets coming from the host stack. * They have been put in the queue by netmap_start() so we * need to protect access to the kring using a lock. * * This routine also does the selrecord if called from the poll handler * (we know because td != NULL). * * NOTE: on linux, selrecord() is defined as a macro and uses pwait * as an additional hidden argument. */ static void netmap_sync_from_host(struct netmap_adapter *na, struct thread *td, void *pwait) { struct netmap_kring *kring = &na->rx_rings[na->num_rx_rings]; struct netmap_ring *ring = kring->ring; u_int j, n, lim = kring->nkr_num_slots; u_int k = ring->cur, resvd = ring->reserved; (void)pwait; /* disable unused warnings */ na->nm_lock(na->ifp, NETMAP_CORE_LOCK, 0); if (k >= lim) { netmap_ring_reinit(kring); return; } /* new packets are already set in nr_hwavail */ /* skip past packets that userspace has released */ j = kring->nr_hwcur; if (resvd > 0) { if (resvd + ring->avail >= lim + 1) { D("XXX invalid reserve/avail %d %d", resvd, ring->avail); ring->reserved = resvd = 0; // XXX panic... } k = (k >= resvd) ? k - resvd : k + lim - resvd; } if (j != k) { n = k >= j ? k - j : k + lim - j; kring->nr_hwavail -= n; kring->nr_hwcur = k; } k = ring->avail = kring->nr_hwavail - resvd; if (k == 0 && td) selrecord(td, &kring->si); if (k && (netmap_verbose & NM_VERB_HOST)) D("%d pkts from stack", k); na->nm_lock(na->ifp, NETMAP_CORE_UNLOCK, 0); } /* * get a refcounted reference to an interface. * Return ENXIO if the interface does not exist, EINVAL if netmap * is not supported by the interface. * If successful, hold a reference. */ static int get_ifp(const char *name, struct ifnet **ifp) { #ifdef NM_BRIDGE struct ifnet *iter = NULL; do { struct nm_bridge *b; int i, l, cand = -1; if (strncmp(name, NM_NAME, sizeof(NM_NAME) - 1)) break; b = nm_find_bridge(name); if (b == NULL) { D("no bridges available for '%s'", name); return (ENXIO); } /* XXX locking */ BDG_LOCK(b); /* lookup in the local list of ports */ for (i = 0; i < NM_BDG_MAXPORTS; i++) { iter = b->bdg_ports[i]; if (iter == NULL) { if (cand == -1) cand = i; /* potential insert point */ continue; } if (!strcmp(iter->if_xname, name)) { ADD_BDG_REF(iter); ND("found existing interface"); BDG_UNLOCK(b); break; } } if (i < NM_BDG_MAXPORTS) /* already unlocked */ break; if (cand == -1) { D("bridge full, cannot create new port"); no_port: BDG_UNLOCK(b); *ifp = NULL; return EINVAL; } ND("create new bridge port %s", name); /* space for forwarding list after the ifnet */ l = sizeof(*iter) + sizeof(struct nm_bdg_fwd)*NM_BDG_BATCH ; iter = malloc(l, M_DEVBUF, M_NOWAIT | M_ZERO); if (!iter) goto no_port; strcpy(iter->if_xname, name); bdg_netmap_attach(iter); b->bdg_ports[cand] = iter; iter->if_bridge = b; ADD_BDG_REF(iter); BDG_UNLOCK(b); ND("attaching virtual bridge %p", b); } while (0); *ifp = iter; if (! *ifp) #endif /* NM_BRIDGE */ *ifp = ifunit_ref(name); if (*ifp == NULL) return (ENXIO); /* can do this if the capability exists and if_pspare[0] * points to the netmap descriptor. */ if (NETMAP_CAPABLE(*ifp)) return 0; /* valid pointer, we hold the refcount */ nm_if_rele(*ifp); return EINVAL; // not NETMAP capable } /* * Error routine called when txsync/rxsync detects an error. * Can't do much more than resetting cur = hwcur, avail = hwavail. * Return 1 on reinit. * * This routine is only called by the upper half of the kernel. * It only reads hwcur (which is changed only by the upper half, too) * and hwavail (which may be changed by the lower half, but only on * a tx ring and only to increase it, so any error will be recovered * on the next call). For the above, we don't strictly need to call * it under lock. */ int netmap_ring_reinit(struct netmap_kring *kring) { struct netmap_ring *ring = kring->ring; u_int i, lim = kring->nkr_num_slots - 1; int errors = 0; RD(10, "called for %s", kring->na->ifp->if_xname); if (ring->cur > lim) errors++; for (i = 0; i <= lim; i++) { u_int idx = ring->slot[i].buf_idx; u_int len = ring->slot[i].len; if (idx < 2 || idx >= netmap_total_buffers) { if (!errors++) D("bad buffer at slot %d idx %d len %d ", i, idx, len); ring->slot[i].buf_idx = 0; ring->slot[i].len = 0; } else if (len > NETMAP_BUF_SIZE) { ring->slot[i].len = 0; if (!errors++) D("bad len %d at slot %d idx %d", len, i, idx); } } if (errors) { int pos = kring - kring->na->tx_rings; int n = kring->na->num_tx_rings + 1; RD(10, "total %d errors", errors); errors++; RD(10, "%s %s[%d] reinit, cur %d -> %d avail %d -> %d", kring->na->ifp->if_xname, pos < n ? "TX" : "RX", pos < n ? pos : pos - n, ring->cur, kring->nr_hwcur, ring->avail, kring->nr_hwavail); ring->cur = kring->nr_hwcur; ring->avail = kring->nr_hwavail; } return (errors ? 1 : 0); } /* * Set the ring ID. For devices with a single queue, a request * for all rings is the same as a single ring. */ static int netmap_set_ringid(struct netmap_priv_d *priv, u_int ringid) { struct ifnet *ifp = priv->np_ifp; struct netmap_adapter *na = NA(ifp); u_int i = ringid & NETMAP_RING_MASK; /* initially (np_qfirst == np_qlast) we don't want to lock */ int need_lock = (priv->np_qfirst != priv->np_qlast); int lim = na->num_rx_rings; if (na->num_tx_rings > lim) lim = na->num_tx_rings; if ( (ringid & NETMAP_HW_RING) && i >= lim) { D("invalid ring id %d", i); return (EINVAL); } if (need_lock) na->nm_lock(ifp, NETMAP_CORE_LOCK, 0); priv->np_ringid = ringid; if (ringid & NETMAP_SW_RING) { priv->np_qfirst = NETMAP_SW_RING; priv->np_qlast = 0; } else if (ringid & NETMAP_HW_RING) { priv->np_qfirst = i; priv->np_qlast = i + 1; } else { priv->np_qfirst = 0; priv->np_qlast = NETMAP_HW_RING ; } priv->np_txpoll = (ringid & NETMAP_NO_TX_POLL) ? 0 : 1; if (need_lock) na->nm_lock(ifp, NETMAP_CORE_UNLOCK, 0); if (netmap_verbose) { if (ringid & NETMAP_SW_RING) D("ringid %s set to SW RING", ifp->if_xname); else if (ringid & NETMAP_HW_RING) D("ringid %s set to HW RING %d", ifp->if_xname, priv->np_qfirst); else D("ringid %s set to all %d HW RINGS", ifp->if_xname, lim); } return 0; } /* * ioctl(2) support for the "netmap" device. * * Following a list of accepted commands: * - NIOCGINFO * - SIOCGIFADDR just for convenience * - NIOCREGIF * - NIOCUNREGIF * - NIOCTXSYNC * - NIOCRXSYNC * * Return 0 on success, errno otherwise. */ static int netmap_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) { struct netmap_priv_d *priv = NULL; struct ifnet *ifp; struct nmreq *nmr = (struct nmreq *) data; struct netmap_adapter *na; int error; u_int i, lim; struct netmap_if *nifp; (void)dev; /* UNUSED */ (void)fflag; /* UNUSED */ #ifdef linux #define devfs_get_cdevpriv(pp) \ ({ *(struct netmap_priv_d **)pp = ((struct file *)td)->private_data; \ (*pp ? 0 : ENOENT); }) /* devfs_set_cdevpriv cannot fail on linux */ #define devfs_set_cdevpriv(p, fn) \ ({ ((struct file *)td)->private_data = p; (p ? 0 : EINVAL); }) #define devfs_clear_cdevpriv() do { \ netmap_dtor(priv); ((struct file *)td)->private_data = 0; \ } while (0) #endif /* linux */ CURVNET_SET(TD_TO_VNET(td)); error = devfs_get_cdevpriv((void **)&priv); if (error) { CURVNET_RESTORE(); /* XXX ENOENT should be impossible, since the priv * is now created in the open */ return (error == ENOENT ? ENXIO : error); } nmr->nr_name[sizeof(nmr->nr_name) - 1] = '\0'; /* truncate name */ switch (cmd) { case NIOCGINFO: /* return capabilities etc */ if (nmr->nr_version != NETMAP_API) { D("API mismatch got %d have %d", nmr->nr_version, NETMAP_API); nmr->nr_version = NETMAP_API; error = EINVAL; break; } /* update configuration */ error = netmap_get_memory(priv); ND("get_memory returned %d", error); if (error) break; /* memsize is always valid */ nmr->nr_memsize = nm_mem.nm_totalsize; nmr->nr_offset = 0; nmr->nr_rx_rings = nmr->nr_tx_rings = 0; nmr->nr_rx_slots = nmr->nr_tx_slots = 0; if (nmr->nr_name[0] == '\0') /* just get memory info */ break; error = get_ifp(nmr->nr_name, &ifp); /* get a refcount */ if (error) break; na = NA(ifp); /* retrieve netmap_adapter */ netmap_update_config(na); nmr->nr_rx_rings = na->num_rx_rings; nmr->nr_tx_rings = na->num_tx_rings; nmr->nr_rx_slots = na->num_rx_desc; nmr->nr_tx_slots = na->num_tx_desc; nm_if_rele(ifp); /* return the refcount */ break; case NIOCREGIF: if (nmr->nr_version != NETMAP_API) { nmr->nr_version = NETMAP_API; error = EINVAL; break; } /* ensure allocators are ready */ error = netmap_get_memory(priv); ND("get_memory returned %d", error); if (error) break; /* protect access to priv from concurrent NIOCREGIF */ NMA_LOCK(); if (priv->np_ifp != NULL) { /* thread already registered */ error = netmap_set_ringid(priv, nmr->nr_ringid); NMA_UNLOCK(); break; } /* find the interface and a reference */ error = get_ifp(nmr->nr_name, &ifp); /* keep reference */ if (error) { NMA_UNLOCK(); break; } na = NA(ifp); /* retrieve netmap adapter */ for (i = 10; i > 0; i--) { na->nm_lock(ifp, NETMAP_REG_LOCK, 0); if (!NETMAP_DELETING(na)) break; na->nm_lock(ifp, NETMAP_REG_UNLOCK, 0); tsleep(na, 0, "NIOCREGIF", hz/10); } if (i == 0) { D("too many NIOCREGIF attempts, give up"); error = EINVAL; nm_if_rele(ifp); /* return the refcount */ NMA_UNLOCK(); break; } /* ring configuration may have changed, fetch from the card */ netmap_update_config(na); priv->np_ifp = ifp; /* store the reference */ error = netmap_set_ringid(priv, nmr->nr_ringid); if (error) goto error; nifp = netmap_if_new(nmr->nr_name, na); if (nifp == NULL) { /* allocation failed */ error = ENOMEM; } else if (ifp->if_capenable & IFCAP_NETMAP) { /* was already set */ } else { /* Otherwise set the card in netmap mode * and make it use the shared buffers. */ for (i = 0 ; i < na->num_tx_rings + 1; i++) mtx_init(&na->tx_rings[i].q_lock, "nm_txq_lock", MTX_NETWORK_LOCK, MTX_DEF); for (i = 0 ; i < na->num_rx_rings + 1; i++) { mtx_init(&na->rx_rings[i].q_lock, "nm_rxq_lock", MTX_NETWORK_LOCK, MTX_DEF); } error = na->nm_register(ifp, 1); /* mode on */ if (error) { netmap_dtor_locked(priv); netmap_if_free(nifp); } } if (error) { /* reg. failed, release priv and ref */ error: na->nm_lock(ifp, NETMAP_REG_UNLOCK, 0); nm_if_rele(ifp); /* return the refcount */ priv->np_ifp = NULL; priv->np_nifp = NULL; NMA_UNLOCK(); break; } na->nm_lock(ifp, NETMAP_REG_UNLOCK, 0); /* the following assignment is a commitment. * Readers (i.e., poll and *SYNC) check for * np_nifp != NULL without locking */ wmb(); /* make sure previous writes are visible to all CPUs */ priv->np_nifp = nifp; NMA_UNLOCK(); /* return the offset of the netmap_if object */ nmr->nr_rx_rings = na->num_rx_rings; nmr->nr_tx_rings = na->num_tx_rings; nmr->nr_rx_slots = na->num_rx_desc; nmr->nr_tx_slots = na->num_tx_desc; nmr->nr_memsize = nm_mem.nm_totalsize; nmr->nr_offset = netmap_if_offset(nifp); break; case NIOCUNREGIF: // XXX we have no data here ? D("deprecated, data is %p", nmr); error = EINVAL; break; case NIOCTXSYNC: case NIOCRXSYNC: nifp = priv->np_nifp; if (nifp == NULL) { error = ENXIO; break; } rmb(); /* make sure following reads are not from cache */ ifp = priv->np_ifp; /* we have a reference */ if (ifp == NULL) { D("Internal error: nifp != NULL && ifp == NULL"); error = ENXIO; break; } na = NA(ifp); /* retrieve netmap adapter */ if (priv->np_qfirst == NETMAP_SW_RING) { /* host rings */ if (cmd == NIOCTXSYNC) netmap_sync_to_host(na); else netmap_sync_from_host(na, NULL, NULL); break; } /* find the last ring to scan */ lim = priv->np_qlast; if (lim == NETMAP_HW_RING) lim = (cmd == NIOCTXSYNC) ? na->num_tx_rings : na->num_rx_rings; for (i = priv->np_qfirst; i < lim; i++) { if (cmd == NIOCTXSYNC) { struct netmap_kring *kring = &na->tx_rings[i]; if (netmap_verbose & NM_VERB_TXSYNC) D("pre txsync ring %d cur %d hwcur %d", i, kring->ring->cur, kring->nr_hwcur); na->nm_txsync(ifp, i, 1 /* do lock */); if (netmap_verbose & NM_VERB_TXSYNC) D("post txsync ring %d cur %d hwcur %d", i, kring->ring->cur, kring->nr_hwcur); } else { na->nm_rxsync(ifp, i, 1 /* do lock */); microtime(&na->rx_rings[i].ring->ts); } } break; #ifdef __FreeBSD__ case BIOCIMMEDIATE: case BIOCGHDRCMPLT: case BIOCSHDRCMPLT: case BIOCSSEESENT: D("ignore BIOCIMMEDIATE/BIOCSHDRCMPLT/BIOCSHDRCMPLT/BIOCSSEESENT"); break; default: /* allow device-specific ioctls */ { struct socket so; bzero(&so, sizeof(so)); error = get_ifp(nmr->nr_name, &ifp); /* keep reference */ if (error) break; so.so_vnet = ifp->if_vnet; // so->so_proto not null. error = ifioctl(&so, cmd, data, td); nm_if_rele(ifp); break; } #else /* linux */ default: error = EOPNOTSUPP; #endif /* linux */ } CURVNET_RESTORE(); return (error); } /* * select(2) and poll(2) handlers for the "netmap" device. * * Can be called for one or more queues. * Return true the event mask corresponding to ready events. * If there are no ready events, do a selrecord on either individual * selfd or on the global one. * Device-dependent parts (locking and sync of tx/rx rings) * are done through callbacks. * * On linux, arguments are really pwait, the poll table, and 'td' is struct file * * The first one is remapped to pwait as selrecord() uses the name as an * hidden argument. */ static int netmap_poll(struct cdev *dev, int events, struct thread *td) { struct netmap_priv_d *priv = NULL; struct netmap_adapter *na; struct ifnet *ifp; struct netmap_kring *kring; u_int core_lock, i, check_all, want_tx, want_rx, revents = 0; u_int lim_tx, lim_rx; enum {NO_CL, NEED_CL, LOCKED_CL }; /* see below */ void *pwait = dev; /* linux compatibility */ (void)pwait; if (devfs_get_cdevpriv((void **)&priv) != 0 || priv == NULL) return POLLERR; if (priv->np_nifp == NULL) { D("No if registered"); return POLLERR; } rmb(); /* make sure following reads are not from cache */ ifp = priv->np_ifp; // XXX check for deleting() ? if ( (ifp->if_capenable & IFCAP_NETMAP) == 0) return POLLERR; if (netmap_verbose & 0x8000) D("device %s events 0x%x", ifp->if_xname, events); want_tx = events & (POLLOUT | POLLWRNORM); want_rx = events & (POLLIN | POLLRDNORM); na = NA(ifp); /* retrieve netmap adapter */ lim_tx = na->num_tx_rings; lim_rx = na->num_rx_rings; /* how many queues we are scanning */ if (priv->np_qfirst == NETMAP_SW_RING) { if (priv->np_txpoll || want_tx) { /* push any packets up, then we are always ready */ kring = &na->tx_rings[lim_tx]; netmap_sync_to_host(na); revents |= want_tx; } if (want_rx) { kring = &na->rx_rings[lim_rx]; if (kring->ring->avail == 0) netmap_sync_from_host(na, td, dev); if (kring->ring->avail > 0) { revents |= want_rx; } } return (revents); } /* * check_all is set if the card has more than one queue and * the client is polling all of them. If true, we sleep on * the "global" selfd, otherwise we sleep on individual selfd * (we can only sleep on one of them per direction). * The interrupt routine in the driver should always wake on * the individual selfd, and also on the global one if the card * has more than one ring. * * If the card has only one lock, we just use that. * If the card has separate ring locks, we just use those * unless we are doing check_all, in which case the whole * loop is wrapped by the global lock. * We acquire locks only when necessary: if poll is called * when buffers are available, we can just return without locks. * * rxsync() is only called if we run out of buffers on a POLLIN. * txsync() is called if we run out of buffers on POLLOUT, or * there are pending packets to send. The latter can be disabled * passing NETMAP_NO_TX_POLL in the NIOCREG call. */ check_all = (priv->np_qlast == NETMAP_HW_RING) && (lim_tx > 1 || lim_rx > 1); /* * core_lock indicates what to do with the core lock. * The core lock is used when either the card has no individual * locks, or it has individual locks but we are cheking all * rings so we need the core lock to avoid missing wakeup events. * * It has three possible states: * NO_CL we don't need to use the core lock, e.g. * because we are protected by individual locks. * NEED_CL we need the core lock. In this case, when we * call the lock routine, move to LOCKED_CL * to remember to release the lock once done. * LOCKED_CL core lock is set, so we need to release it. */ core_lock = (check_all || !na->separate_locks) ? NEED_CL : NO_CL; #ifdef NM_BRIDGE /* the bridge uses separate locks */ if (na->nm_register == bdg_netmap_reg) { ND("not using core lock for %s", ifp->if_xname); core_lock = NO_CL; } #endif /* NM_BRIDGE */ if (priv->np_qlast != NETMAP_HW_RING) { lim_tx = lim_rx = priv->np_qlast; } /* * We start with a lock free round which is good if we have * data available. If this fails, then lock and call the sync * routines. */ for (i = priv->np_qfirst; want_rx && i < lim_rx; i++) { kring = &na->rx_rings[i]; if (kring->ring->avail > 0) { revents |= want_rx; want_rx = 0; /* also breaks the loop */ } } for (i = priv->np_qfirst; want_tx && i < lim_tx; i++) { kring = &na->tx_rings[i]; if (kring->ring->avail > 0) { revents |= want_tx; want_tx = 0; /* also breaks the loop */ } } /* * If we to push packets out (priv->np_txpoll) or want_tx is * still set, we do need to run the txsync calls (on all rings, * to avoid that the tx rings stall). */ if (priv->np_txpoll || want_tx) { for (i = priv->np_qfirst; i < lim_tx; i++) { kring = &na->tx_rings[i]; /* * Skip the current ring if want_tx == 0 * (we have already done a successful sync on * a previous ring) AND kring->cur == kring->hwcur * (there are no pending transmissions for this ring). */ if (!want_tx && kring->ring->cur == kring->nr_hwcur) continue; if (core_lock == NEED_CL) { na->nm_lock(ifp, NETMAP_CORE_LOCK, 0); core_lock = LOCKED_CL; } if (na->separate_locks) na->nm_lock(ifp, NETMAP_TX_LOCK, i); if (netmap_verbose & NM_VERB_TXSYNC) D("send %d on %s %d", kring->ring->cur, ifp->if_xname, i); if (na->nm_txsync(ifp, i, 0 /* no lock */)) revents |= POLLERR; /* Check avail/call selrecord only if called with POLLOUT */ if (want_tx) { if (kring->ring->avail > 0) { /* stop at the first ring. We don't risk * starvation. */ revents |= want_tx; want_tx = 0; } else if (!check_all) selrecord(td, &kring->si); } if (na->separate_locks) na->nm_lock(ifp, NETMAP_TX_UNLOCK, i); } } /* * now if want_rx is still set we need to lock and rxsync. * Do it on all rings because otherwise we starve. */ if (want_rx) { for (i = priv->np_qfirst; i < lim_rx; i++) { kring = &na->rx_rings[i]; if (core_lock == NEED_CL) { na->nm_lock(ifp, NETMAP_CORE_LOCK, 0); core_lock = LOCKED_CL; } if (na->separate_locks) na->nm_lock(ifp, NETMAP_RX_LOCK, i); if (na->nm_rxsync(ifp, i, 0 /* no lock */)) revents |= POLLERR; if (netmap_no_timestamp == 0 || kring->ring->flags & NR_TIMESTAMP) { microtime(&kring->ring->ts); } if (kring->ring->avail > 0) revents |= want_rx; else if (!check_all) selrecord(td, &kring->si); if (na->separate_locks) na->nm_lock(ifp, NETMAP_RX_UNLOCK, i); } } if (check_all && revents == 0) { /* signal on the global queue */ if (want_tx) selrecord(td, &na->tx_si); if (want_rx) selrecord(td, &na->rx_si); } if (core_lock == LOCKED_CL) na->nm_lock(ifp, NETMAP_CORE_UNLOCK, 0); return (revents); } /*------- driver support routines ------*/ /* * default lock wrapper. */ static void netmap_lock_wrapper(struct ifnet *dev, int what, u_int queueid) { struct netmap_adapter *na = NA(dev); switch (what) { #ifdef linux /* some system do not need lock on register */ case NETMAP_REG_LOCK: case NETMAP_REG_UNLOCK: break; #endif /* linux */ case NETMAP_CORE_LOCK: mtx_lock(&na->core_lock); break; case NETMAP_CORE_UNLOCK: mtx_unlock(&na->core_lock); break; case NETMAP_TX_LOCK: mtx_lock(&na->tx_rings[queueid].q_lock); break; case NETMAP_TX_UNLOCK: mtx_unlock(&na->tx_rings[queueid].q_lock); break; case NETMAP_RX_LOCK: mtx_lock(&na->rx_rings[queueid].q_lock); break; case NETMAP_RX_UNLOCK: mtx_unlock(&na->rx_rings[queueid].q_lock); break; } } /* * Initialize a ``netmap_adapter`` object created by driver on attach. * We allocate a block of memory with room for a struct netmap_adapter * plus two sets of N+2 struct netmap_kring (where N is the number * of hardware rings): * krings 0..N-1 are for the hardware queues. * kring N is for the host stack queue * kring N+1 is only used for the selinfo for all queues. * Return 0 on success, ENOMEM otherwise. * * By default the receive and transmit adapter ring counts are both initialized * to num_queues. na->num_tx_rings can be set for cards with different tx/rx * setups. */ int netmap_attach(struct netmap_adapter *arg, int num_queues) { struct netmap_adapter *na = NULL; struct ifnet *ifp = arg ? arg->ifp : NULL; if (arg == NULL || ifp == NULL) goto fail; na = malloc(sizeof(*na), M_DEVBUF, M_NOWAIT | M_ZERO); if (na == NULL) goto fail; WNA(ifp) = na; *na = *arg; /* copy everything, trust the driver to not pass junk */ NETMAP_SET_CAPABLE(ifp); if (na->num_tx_rings == 0) na->num_tx_rings = num_queues; na->num_rx_rings = num_queues; na->refcount = na->na_single = na->na_multi = 0; /* Core lock initialized here, others after netmap_if_new. */ mtx_init(&na->core_lock, "netmap core lock", MTX_NETWORK_LOCK, MTX_DEF); if (na->nm_lock == NULL) { ND("using default locks for %s", ifp->if_xname); na->nm_lock = netmap_lock_wrapper; } #ifdef linux if (ifp->netdev_ops) { ND("netdev_ops %p", ifp->netdev_ops); /* prepare a clone of the netdev ops */ na->nm_ndo = *ifp->netdev_ops; } na->nm_ndo.ndo_start_xmit = linux_netmap_start; #endif D("success for %s", ifp->if_xname); return 0; fail: D("fail, arg %p ifp %p na %p", arg, ifp, na); return (na ? EINVAL : ENOMEM); } /* * Free the allocated memory linked to the given ``netmap_adapter`` * object. */ void netmap_detach(struct ifnet *ifp) { struct netmap_adapter *na = NA(ifp); if (!na) return; mtx_destroy(&na->core_lock); if (na->tx_rings) { /* XXX should not happen */ D("freeing leftover tx_rings"); free(na->tx_rings, M_DEVBUF); } bzero(na, sizeof(*na)); WNA(ifp) = NULL; free(na, M_DEVBUF); } /* * Intercept packets from the network stack and pass them * to netmap as incoming packets on the 'software' ring. * We are not locked when called. */ int netmap_start(struct ifnet *ifp, struct mbuf *m) { struct netmap_adapter *na = NA(ifp); struct netmap_kring *kring = &na->rx_rings[na->num_rx_rings]; u_int i, len = MBUF_LEN(m); u_int error = EBUSY, lim = kring->nkr_num_slots - 1; struct netmap_slot *slot; if (netmap_verbose & NM_VERB_HOST) D("%s packet %d len %d from the stack", ifp->if_xname, kring->nr_hwcur + kring->nr_hwavail, len); na->nm_lock(ifp, NETMAP_CORE_LOCK, 0); if (kring->nr_hwavail >= lim) { if (netmap_verbose) D("stack ring %s full\n", ifp->if_xname); goto done; /* no space */ } if (len > NETMAP_BUF_SIZE) { D("drop packet size %d > %d", len, NETMAP_BUF_SIZE); goto done; /* too long for us */ } /* compute the insert position */ i = kring->nr_hwcur + kring->nr_hwavail; if (i > lim) i -= lim + 1; slot = &kring->ring->slot[i]; m_copydata(m, 0, len, NMB(slot)); slot->len = len; kring->nr_hwavail++; if (netmap_verbose & NM_VERB_HOST) D("wake up host ring %s %d", na->ifp->if_xname, na->num_rx_rings); selwakeuppri(&kring->si, PI_NET); error = 0; done: na->nm_lock(ifp, NETMAP_CORE_UNLOCK, 0); /* release the mbuf in either cases of success or failure. As an * alternative, put the mbuf in a free list and free the list * only when really necessary. */ m_freem(m); return (error); } /* * netmap_reset() is called by the driver routines when reinitializing * a ring. The driver is in charge of locking to protect the kring. * If netmap mode is not set just return NULL. */ struct netmap_slot * netmap_reset(struct netmap_adapter *na, enum txrx tx, int n, u_int new_cur) { struct netmap_kring *kring; int new_hwofs, lim; if (na == NULL) return NULL; /* no netmap support here */ if (!(na->ifp->if_capenable & IFCAP_NETMAP)) return NULL; /* nothing to reinitialize */ if (tx == NR_TX) { if (n >= na->num_tx_rings) return NULL; kring = na->tx_rings + n; new_hwofs = kring->nr_hwcur - new_cur; } else { if (n >= na->num_rx_rings) return NULL; kring = na->rx_rings + n; new_hwofs = kring->nr_hwcur + kring->nr_hwavail - new_cur; } lim = kring->nkr_num_slots - 1; if (new_hwofs > lim) new_hwofs -= lim + 1; /* Alwayws set the new offset value and realign the ring. */ kring->nkr_hwofs = new_hwofs; if (tx == NR_TX) kring->nr_hwavail = kring->nkr_num_slots - 1; ND(10, "new hwofs %d on %s %s[%d]", kring->nkr_hwofs, na->ifp->if_xname, tx == NR_TX ? "TX" : "RX", n); #if 0 // def linux /* XXX check that the mappings are correct */ /* need ring_nr, adapter->pdev, direction */ buffer_info->dma = dma_map_single(&pdev->dev, addr, adapter->rx_buffer_len, DMA_FROM_DEVICE); if (dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)) { D("error mapping rx netmap buffer %d", i); // XXX fix error handling } #endif /* linux */ /* * Wakeup on the individual and global lock * We do the wakeup here, but the ring is not yet reconfigured. * However, we are under lock so there are no races. */ selwakeuppri(&kring->si, PI_NET); selwakeuppri(tx == NR_TX ? &na->tx_si : &na->rx_si, PI_NET); return kring->ring->slot; } /* * Default functions to handle rx/tx interrupts * we have 4 cases: * 1 ring, single lock: * lock(core); wake(i=0); unlock(core) * N rings, single lock: * lock(core); wake(i); wake(N+1) unlock(core) * 1 ring, separate locks: (i=0) * lock(i); wake(i); unlock(i) * N rings, separate locks: * lock(i); wake(i); unlock(i); lock(core) wake(N+1) unlock(core) * work_done is non-null on the RX path. */ int netmap_rx_irq(struct ifnet *ifp, int q, int *work_done) { struct netmap_adapter *na; struct netmap_kring *r; NM_SELINFO_T *main_wq; if (!(ifp->if_capenable & IFCAP_NETMAP)) return 0; ND(5, "received %s queue %d", work_done ? "RX" : "TX" , q); na = NA(ifp); if (na->na_flags & NAF_SKIP_INTR) { ND("use regular interrupt"); return 0; } if (work_done) { /* RX path */ if (q >= na->num_rx_rings) return 0; // regular queue r = na->rx_rings + q; r->nr_kflags |= NKR_PENDINTR; main_wq = (na->num_rx_rings > 1) ? &na->rx_si : NULL; } else { /* tx path */ if (q >= na->num_tx_rings) return 0; // regular queue r = na->tx_rings + q; main_wq = (na->num_tx_rings > 1) ? &na->tx_si : NULL; work_done = &q; /* dummy */ } if (na->separate_locks) { mtx_lock(&r->q_lock); selwakeuppri(&r->si, PI_NET); mtx_unlock(&r->q_lock); if (main_wq) { mtx_lock(&na->core_lock); selwakeuppri(main_wq, PI_NET); mtx_unlock(&na->core_lock); } } else { mtx_lock(&na->core_lock); selwakeuppri(&r->si, PI_NET); if (main_wq) selwakeuppri(main_wq, PI_NET); mtx_unlock(&na->core_lock); } *work_done = 1; /* do not fire napi again */ return 1; } #ifdef linux /* linux-specific routines */ /* * Remap linux arguments into the FreeBSD call. * - pwait is the poll table, passed as 'dev'; * If pwait == NULL someone else already woke up before. We can report * events but they are filtered upstream. * If pwait != NULL, then pwait->key contains the list of events. * - events is computed from pwait as above. * - file is passed as 'td'; */ static u_int linux_netmap_poll(struct file * file, struct poll_table_struct *pwait) { #if LINUX_VERSION_CODE < KERNEL_VERSION(3,4,0) int events = pwait ? pwait->key : POLLIN | POLLOUT; #else /* in 3.4.0 field 'key' was renamed to '_key' */ int events = pwait ? pwait->_key : POLLIN | POLLOUT; #endif return netmap_poll((void *)pwait, events, (void *)file); } static int linux_netmap_mmap(struct file *f, struct vm_area_struct *vma) { int lut_skip, i, j; int user_skip = 0; struct lut_entry *l_entry; int error = 0; unsigned long off, tomap; /* * vma->vm_start: start of mapping user address space * vma->vm_end: end of the mapping user address space * vma->vm_pfoff: offset of first page in the device */ // XXX security checks error = netmap_get_memory(f->private_data); ND("get_memory returned %d", error); if (error) return -error; off = vma->vm_pgoff << PAGE_SHIFT; /* offset in bytes */ tomap = vma->vm_end - vma->vm_start; for (i = 0; i < NETMAP_POOLS_NR; i++) { /* loop through obj_pools */ const struct netmap_obj_pool *p = &nm_mem.pools[i]; /* * In each pool memory is allocated in clusters * of size _clustsize, each containing clustentries * entries. For each object k we already store the * vtophys mapping in lut[k] so we use that, scanning * the lut[] array in steps of clustentries, * and we map each cluster (not individual pages, * it would be overkill). */ /* * We interpret vm_pgoff as an offset into the whole * netmap memory, as if all clusters where contiguous. */ for (lut_skip = 0, j = 0; j < p->_numclusters; j++, lut_skip += p->clustentries) { unsigned long paddr, mapsize; if (p->_clustsize <= off) { off -= p->_clustsize; continue; } l_entry = &p->lut[lut_skip]; /* first obj in the cluster */ paddr = l_entry->paddr + off; mapsize = p->_clustsize - off; off = 0; if (mapsize > tomap) mapsize = tomap; ND("remap_pfn_range(%lx, %lx, %lx)", vma->vm_start + user_skip, paddr >> PAGE_SHIFT, mapsize); if (remap_pfn_range(vma, vma->vm_start + user_skip, paddr >> PAGE_SHIFT, mapsize, vma->vm_page_prot)) return -EAGAIN; // XXX check return value user_skip += mapsize; tomap -= mapsize; if (tomap == 0) goto done; } } done: return 0; } static netdev_tx_t linux_netmap_start(struct sk_buff *skb, struct net_device *dev) { netmap_start(dev, skb); return (NETDEV_TX_OK); } #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) // XXX was 38 #define LIN_IOCTL_NAME .ioctl int linux_netmap_ioctl(struct inode *inode, struct file *file, u_int cmd, u_long data /* arg */) #else #define LIN_IOCTL_NAME .unlocked_ioctl long linux_netmap_ioctl(struct file *file, u_int cmd, u_long data /* arg */) #endif { int ret; struct nmreq nmr; bzero(&nmr, sizeof(nmr)); if (data && copy_from_user(&nmr, (void *)data, sizeof(nmr) ) != 0) return -EFAULT; ret = netmap_ioctl(NULL, cmd, (caddr_t)&nmr, 0, (void *)file); if (data && copy_to_user((void*)data, &nmr, sizeof(nmr) ) != 0) return -EFAULT; return -ret; } static int netmap_release(struct inode *inode, struct file *file) { (void)inode; /* UNUSED */ if (file->private_data) netmap_dtor(file->private_data); return (0); } static int linux_netmap_open(struct inode *inode, struct file *file) { struct netmap_priv_d *priv; (void)inode; /* UNUSED */ priv = malloc(sizeof(struct netmap_priv_d), M_DEVBUF, M_NOWAIT | M_ZERO); if (priv == NULL) return -ENOMEM; file->private_data = priv; return (0); } static struct file_operations netmap_fops = { .open = linux_netmap_open, .mmap = linux_netmap_mmap, LIN_IOCTL_NAME = linux_netmap_ioctl, .poll = linux_netmap_poll, .release = netmap_release, }; static struct miscdevice netmap_cdevsw = { /* same name as FreeBSD */ MISC_DYNAMIC_MINOR, "netmap", &netmap_fops, }; static int netmap_init(void); static void netmap_fini(void); /* Errors have negative values on linux */ static int linux_netmap_init(void) { return -netmap_init(); } module_init(linux_netmap_init); module_exit(netmap_fini); /* export certain symbols to other modules */ EXPORT_SYMBOL(netmap_attach); // driver attach routines EXPORT_SYMBOL(netmap_detach); // driver detach routines EXPORT_SYMBOL(netmap_ring_reinit); // ring init on error EXPORT_SYMBOL(netmap_buffer_lut); EXPORT_SYMBOL(netmap_total_buffers); // index check EXPORT_SYMBOL(netmap_buffer_base); EXPORT_SYMBOL(netmap_reset); // ring init routines EXPORT_SYMBOL(netmap_buf_size); EXPORT_SYMBOL(netmap_rx_irq); // default irq handler EXPORT_SYMBOL(netmap_no_pendintr); // XXX mitigation - should go away MODULE_AUTHOR("http://info.iet.unipi.it/~luigi/netmap/"); MODULE_DESCRIPTION("The netmap packet I/O framework"); MODULE_LICENSE("Dual BSD/GPL"); /* the code here is all BSD. */ #else /* __FreeBSD__ */ static struct cdevsw netmap_cdevsw = { .d_version = D_VERSION, .d_name = "netmap", .d_open = netmap_open, .d_mmap = netmap_mmap, .d_mmap_single = netmap_mmap_single, .d_ioctl = netmap_ioctl, .d_poll = netmap_poll, .d_close = netmap_close, }; #endif /* __FreeBSD__ */ #ifdef NM_BRIDGE /* *---- support for virtual bridge ----- */ /* ----- FreeBSD if_bridge hash function ------- */ /* * The following hash function is adapted from "Hash Functions" by Bob Jenkins * ("Algorithm Alley", Dr. Dobbs Journal, September 1997). * * http://www.burtleburtle.net/bob/hash/spooky.html */ #define mix(a, b, c) \ do { \ a -= b; a -= c; a ^= (c >> 13); \ b -= c; b -= a; b ^= (a << 8); \ c -= a; c -= b; c ^= (b >> 13); \ a -= b; a -= c; a ^= (c >> 12); \ b -= c; b -= a; b ^= (a << 16); \ c -= a; c -= b; c ^= (b >> 5); \ a -= b; a -= c; a ^= (c >> 3); \ b -= c; b -= a; b ^= (a << 10); \ c -= a; c -= b; c ^= (b >> 15); \ } while (/*CONSTCOND*/0) static __inline uint32_t nm_bridge_rthash(const uint8_t *addr) { uint32_t a = 0x9e3779b9, b = 0x9e3779b9, c = 0; // hask key b += addr[5] << 8; b += addr[4]; a += addr[3] << 24; a += addr[2] << 16; a += addr[1] << 8; a += addr[0]; mix(a, b, c); #define BRIDGE_RTHASH_MASK (NM_BDG_HASH-1) return (c & BRIDGE_RTHASH_MASK); } #undef mix static int bdg_netmap_reg(struct ifnet *ifp, int onoff) { int i, err = 0; struct nm_bridge *b = ifp->if_bridge; BDG_LOCK(b); if (onoff) { /* the interface must be already in the list. * only need to mark the port as active */ ND("should attach %s to the bridge", ifp->if_xname); for (i=0; i < NM_BDG_MAXPORTS; i++) if (b->bdg_ports[i] == ifp) break; if (i == NM_BDG_MAXPORTS) { D("no more ports available"); err = EINVAL; goto done; } ND("setting %s in netmap mode", ifp->if_xname); ifp->if_capenable |= IFCAP_NETMAP; NA(ifp)->bdg_port = i; b->act_ports |= (1<bdg_ports[i] = ifp; } else { /* should be in the list, too -- remove from the mask */ ND("removing %s from netmap mode", ifp->if_xname); ifp->if_capenable &= ~IFCAP_NETMAP; i = NA(ifp)->bdg_port; b->act_ports &= ~(1<bdg_port; uint64_t smac, dmac; struct netmap_slot *slot; struct nm_bridge *b = ifp->if_bridge; ND("prepare to send %d packets, act_ports 0x%x", n, b->act_ports); /* only consider valid destinations */ all_dst = (b->act_ports & ~mysrc); /* first pass: hash and find destinations */ for (i = 0; likely(i < n); i++) { uint8_t *buf = ft[i].buf; dmac = le64toh(*(uint64_t *)(buf)) & 0xffffffffffff; smac = le64toh(*(uint64_t *)(buf + 4)); smac >>= 16; if (unlikely(netmap_verbose)) { uint8_t *s = buf+6, *d = buf; D("%d len %4d %02x:%02x:%02x:%02x:%02x:%02x -> %02x:%02x:%02x:%02x:%02x:%02x", i, ft[i].len, s[0], s[1], s[2], s[3], s[4], s[5], d[0], d[1], d[2], d[3], d[4], d[5]); } /* * The hash is somewhat expensive, there might be some * worthwhile optimizations here. */ if ((buf[6] & 1) == 0) { /* valid src */ uint8_t *s = buf+6; sh = nm_bridge_rthash(buf+6); // XXX hash of source /* update source port forwarding entry */ b->ht[sh].mac = smac; /* XXX expire ? */ b->ht[sh].ports = mysrc; if (netmap_verbose) D("src %02x:%02x:%02x:%02x:%02x:%02x on port %d", s[0], s[1], s[2], s[3], s[4], s[5], NA(ifp)->bdg_port); } dst = 0; if ( (buf[0] & 1) == 0) { /* unicast */ uint8_t *d = buf; dh = nm_bridge_rthash(buf); // XXX hash of dst if (b->ht[dh].mac == dmac) { /* found dst */ dst = b->ht[dh].ports; if (netmap_verbose) D("dst %02x:%02x:%02x:%02x:%02x:%02x to port %x", d[0], d[1], d[2], d[3], d[4], d[5], (uint32_t)(dst >> 16)); } } if (dst == 0) dst = all_dst; dst &= all_dst; /* only consider valid ports */ if (unlikely(netmap_verbose)) D("pkt goes to ports 0x%x", (uint32_t)dst); ft[i].dst = dst; } /* second pass, scan interfaces and forward */ all_dst = (b->act_ports & ~mysrc); for (ifn = 0; all_dst; ifn++) { struct ifnet *dst_ifp = b->bdg_ports[ifn]; struct netmap_adapter *na; struct netmap_kring *kring; struct netmap_ring *ring; int j, lim, sent, locked; if (!dst_ifp) continue; ND("scan port %d %s", ifn, dst_ifp->if_xname); dst = 1 << ifn; if ((dst & all_dst) == 0) /* skip if not set */ continue; all_dst &= ~dst; /* clear current node */ na = NA(dst_ifp); ring = NULL; kring = NULL; lim = sent = locked = 0; /* inside, scan slots */ for (i = 0; likely(i < n); i++) { if ((ft[i].dst & dst) == 0) continue; /* not here */ if (!locked) { kring = &na->rx_rings[0]; ring = kring->ring; lim = kring->nkr_num_slots - 1; na->nm_lock(dst_ifp, NETMAP_RX_LOCK, 0); locked = 1; } if (unlikely(kring->nr_hwavail >= lim)) { if (netmap_verbose) D("rx ring full on %s", ifp->if_xname); break; } j = kring->nr_hwcur + kring->nr_hwavail; if (j > lim) j -= kring->nkr_num_slots; slot = &ring->slot[j]; ND("send %d %d bytes at %s:%d", i, ft[i].len, dst_ifp->if_xname, j); pkt_copy(ft[i].buf, NMB(slot), ft[i].len); slot->len = ft[i].len; kring->nr_hwavail++; sent++; } if (locked) { ND("sent %d on %s", sent, dst_ifp->if_xname); if (sent) selwakeuppri(&kring->si, PI_NET); na->nm_lock(dst_ifp, NETMAP_RX_UNLOCK, 0); } } return 0; } /* * main dispatch routine */ static int bdg_netmap_txsync(struct ifnet *ifp, u_int ring_nr, int do_lock) { struct netmap_adapter *na = NA(ifp); struct netmap_kring *kring = &na->tx_rings[ring_nr]; struct netmap_ring *ring = kring->ring; int i, j, k, lim = kring->nkr_num_slots - 1; struct nm_bdg_fwd *ft = (struct nm_bdg_fwd *)(ifp + 1); int ft_i; /* position in the forwarding table */ k = ring->cur; if (k > lim) return netmap_ring_reinit(kring); if (do_lock) na->nm_lock(ifp, NETMAP_TX_LOCK, ring_nr); if (netmap_bridge <= 0) { /* testing only */ j = k; // used all goto done; } if (netmap_bridge > NM_BDG_BATCH) netmap_bridge = NM_BDG_BATCH; ft_i = 0; /* start from 0 */ for (j = kring->nr_hwcur; likely(j != k); j = unlikely(j == lim) ? 0 : j+1) { struct netmap_slot *slot = &ring->slot[j]; int len = ft[ft_i].len = slot->len; char *buf = ft[ft_i].buf = NMB(slot); prefetch(buf); if (unlikely(len < 14)) continue; if (unlikely(++ft_i == netmap_bridge)) ft_i = nm_bdg_flush(ft, ft_i, ifp); } if (ft_i) ft_i = nm_bdg_flush(ft, ft_i, ifp); /* count how many packets we sent */ i = k - j; if (i < 0) i += kring->nkr_num_slots; kring->nr_hwavail = kring->nkr_num_slots - 1 - i; if (j != k) D("early break at %d/ %d, avail %d", j, k, kring->nr_hwavail); done: kring->nr_hwcur = j; ring->avail = kring->nr_hwavail; if (do_lock) na->nm_lock(ifp, NETMAP_TX_UNLOCK, ring_nr); if (netmap_verbose) D("%s ring %d lock %d", ifp->if_xname, ring_nr, do_lock); return 0; } static int bdg_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock) { struct netmap_adapter *na = NA(ifp); struct netmap_kring *kring = &na->rx_rings[ring_nr]; struct netmap_ring *ring = kring->ring; u_int j, n, lim = kring->nkr_num_slots - 1; u_int k = ring->cur, resvd = ring->reserved; ND("%s ring %d lock %d avail %d", ifp->if_xname, ring_nr, do_lock, kring->nr_hwavail); if (k > lim) return netmap_ring_reinit(kring); if (do_lock) na->nm_lock(ifp, NETMAP_RX_LOCK, ring_nr); /* skip past packets that userspace has released */ j = kring->nr_hwcur; /* netmap ring index */ if (resvd > 0) { if (resvd + ring->avail >= lim + 1) { D("XXX invalid reserve/avail %d %d", resvd, ring->avail); ring->reserved = resvd = 0; // XXX panic... } k = (k >= resvd) ? k - resvd : k + lim + 1 - resvd; } if (j != k) { /* userspace has released some packets. */ n = k - j; if (n < 0) n += kring->nkr_num_slots; ND("userspace releases %d packets", n); for (n = 0; likely(j != k); n++) { struct netmap_slot *slot = &ring->slot[j]; void *addr = NMB(slot); if (addr == netmap_buffer_base) { /* bad buf */ if (do_lock) na->nm_lock(ifp, NETMAP_RX_UNLOCK, ring_nr); return netmap_ring_reinit(kring); } /* decrease refcount for buffer */ slot->flags &= ~NS_BUF_CHANGED; j = unlikely(j == lim) ? 0 : j + 1; } kring->nr_hwavail -= n; kring->nr_hwcur = k; } /* tell userspace that there are new packets */ ring->avail = kring->nr_hwavail - resvd; if (do_lock) na->nm_lock(ifp, NETMAP_RX_UNLOCK, ring_nr); return 0; } static void bdg_netmap_attach(struct ifnet *ifp) { struct netmap_adapter na; ND("attaching virtual bridge"); bzero(&na, sizeof(na)); na.ifp = ifp; na.separate_locks = 1; na.num_tx_desc = NM_BRIDGE_RINGSIZE; na.num_rx_desc = NM_BRIDGE_RINGSIZE; na.nm_txsync = bdg_netmap_txsync; na.nm_rxsync = bdg_netmap_rxsync; na.nm_register = bdg_netmap_reg; netmap_attach(&na, 1); } #endif /* NM_BRIDGE */ static struct cdev *netmap_dev; /* /dev/netmap character device. */ /* * Module loader. * * Create the /dev/netmap device and initialize all global * variables. * * Return 0 on success, errno on failure. */ static int netmap_init(void) { int error; error = netmap_memory_init(); if (error != 0) { printf("netmap: unable to initialize the memory allocator.\n"); return (error); } printf("netmap: loaded module\n"); netmap_dev = make_dev(&netmap_cdevsw, 0, UID_ROOT, GID_WHEEL, 0660, "netmap"); #ifdef NM_BRIDGE { int i; for (i = 0; i < NM_BRIDGES; i++) mtx_init(&nm_bridges[i].bdg_lock, "bdg lock", "bdg_lock", MTX_DEF); } #endif return (error); } /* * Module unloader. * * Free all the memory, and destroy the ``/dev/netmap`` device. */ static void netmap_fini(void) { destroy_dev(netmap_dev); netmap_memory_fini(); printf("netmap: unloaded module.\n"); } #ifdef __FreeBSD__ /* * Kernel entry point. * * Initialize/finalize the module and return. * * Return 0 on success, errno on failure. */ static int netmap_loader(__unused struct module *module, int event, __unused void *arg) { int error = 0; switch (event) { case MOD_LOAD: error = netmap_init(); break; case MOD_UNLOAD: netmap_fini(); break; default: error = EOPNOTSUPP; break; } return (error); } DEV_MODULE(netmap, netmap_loader, NULL); #endif /* __FreeBSD__ */