/* * Copyright (C) 2014-2016 Giuseppe Lettieri * 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. */ /* $FreeBSD$ */ #if defined(__FreeBSD__) #include /* prerequisite */ #include #include #include /* defines used in kernel.h */ #include /* types used in module initialization */ #include #include #include #include #include #include #include /* sockaddrs */ #include #include #include /* bus_dmamap_* */ #include #elif defined(linux) #include "bsd_glue.h" #elif defined(__APPLE__) #warning OSX support is only partial #include "osx_glue.h" #elif defined(_WIN32) #include "win_glue.h" #else #error Unsupported platform #endif /* unsupported */ /* * common headers */ #include #include #include #ifdef WITH_PIPES #define NM_PIPE_MAXSLOTS 4096 static int netmap_default_pipes = 0; /* ignored, kept for compatibility */ SYSBEGIN(vars_pipes); SYSCTL_DECL(_dev_netmap); SYSCTL_INT(_dev_netmap, OID_AUTO, default_pipes, CTLFLAG_RW, &netmap_default_pipes, 0 , ""); SYSEND; /* allocate the pipe array in the parent adapter */ static int nm_pipe_alloc(struct netmap_adapter *na, u_int npipes) { size_t old_len, len; struct netmap_pipe_adapter **npa; if (npipes <= na->na_max_pipes) /* we already have more entries that requested */ return 0; if (npipes < na->na_next_pipe || npipes > NM_MAXPIPES) return EINVAL; old_len = sizeof(struct netmap_pipe_adapter *)*na->na_max_pipes; len = sizeof(struct netmap_pipe_adapter *) * npipes; npa = nm_os_realloc(na->na_pipes, len, old_len); if (npa == NULL) return ENOMEM; na->na_pipes = npa; na->na_max_pipes = npipes; return 0; } /* deallocate the parent array in the parent adapter */ void netmap_pipe_dealloc(struct netmap_adapter *na) { if (na->na_pipes) { if (na->na_next_pipe > 0) { D("freeing not empty pipe array for %s (%d dangling pipes)!", na->name, na->na_next_pipe); } nm_os_free(na->na_pipes); na->na_pipes = NULL; na->na_max_pipes = 0; na->na_next_pipe = 0; } } /* find a pipe endpoint with the given id among the parent's pipes */ static struct netmap_pipe_adapter * netmap_pipe_find(struct netmap_adapter *parent, u_int pipe_id) { int i; struct netmap_pipe_adapter *na; for (i = 0; i < parent->na_next_pipe; i++) { na = parent->na_pipes[i]; if (na->id == pipe_id) { return na; } } return NULL; } /* add a new pipe endpoint to the parent array */ static int netmap_pipe_add(struct netmap_adapter *parent, struct netmap_pipe_adapter *na) { if (parent->na_next_pipe >= parent->na_max_pipes) { u_int npipes = parent->na_max_pipes ? 2*parent->na_max_pipes : 2; int error = nm_pipe_alloc(parent, npipes); if (error) return error; } parent->na_pipes[parent->na_next_pipe] = na; na->parent_slot = parent->na_next_pipe; parent->na_next_pipe++; return 0; } /* remove the given pipe endpoint from the parent array */ static void netmap_pipe_remove(struct netmap_adapter *parent, struct netmap_pipe_adapter *na) { u_int n; n = --parent->na_next_pipe; if (n != na->parent_slot) { struct netmap_pipe_adapter **p = &parent->na_pipes[na->parent_slot]; *p = parent->na_pipes[n]; (*p)->parent_slot = na->parent_slot; } parent->na_pipes[n] = NULL; } int netmap_pipe_txsync(struct netmap_kring *txkring, int flags) { struct netmap_kring *rxkring = txkring->pipe; u_int limit; /* slots to transfer */ u_int j, k, lim_tx = txkring->nkr_num_slots - 1, lim_rx = rxkring->nkr_num_slots - 1; int m, busy; ND("%p: %s %x -> %s", txkring, txkring->name, flags, rxkring->name); ND(2, "before: hwcur %d hwtail %d cur %d head %d tail %d", txkring->nr_hwcur, txkring->nr_hwtail, txkring->rcur, txkring->rhead, txkring->rtail); j = rxkring->nr_hwtail; /* RX */ k = txkring->nr_hwcur; /* TX */ m = txkring->rhead - txkring->nr_hwcur; /* new slots */ if (m < 0) m += txkring->nkr_num_slots; limit = m; m = lim_rx; /* max avail space on destination */ busy = j - rxkring->nr_hwcur; /* busy slots */ if (busy < 0) busy += rxkring->nkr_num_slots; m -= busy; /* subtract busy slots */ ND(2, "m %d limit %d", m, limit); if (m < limit) limit = m; if (limit == 0) { /* either the rxring is full, or nothing to send */ return 0; } while (limit-- > 0) { struct netmap_slot *rs = &rxkring->ring->slot[j]; struct netmap_slot *ts = &txkring->ring->slot[k]; struct netmap_slot tmp; /* swap the slots */ tmp = *rs; *rs = *ts; *ts = tmp; /* report the buffer change */ ts->flags |= NS_BUF_CHANGED; rs->flags |= NS_BUF_CHANGED; j = nm_next(j, lim_rx); k = nm_next(k, lim_tx); } mb(); /* make sure the slots are updated before publishing them */ rxkring->nr_hwtail = j; txkring->nr_hwcur = k; txkring->nr_hwtail = nm_prev(k, lim_tx); ND(2, "after: hwcur %d hwtail %d cur %d head %d tail %d j %d", txkring->nr_hwcur, txkring->nr_hwtail, txkring->rcur, txkring->rhead, txkring->rtail, j); mb(); /* make sure rxkring->nr_hwtail is updated before notifying */ rxkring->nm_notify(rxkring, 0); return 0; } int netmap_pipe_rxsync(struct netmap_kring *rxkring, int flags) { struct netmap_kring *txkring = rxkring->pipe; uint32_t oldhwcur = rxkring->nr_hwcur; ND("%s %x <- %s", rxkring->name, flags, txkring->name); rxkring->nr_hwcur = rxkring->rhead; /* recover user-relased slots */ ND(5, "hwcur %d hwtail %d cur %d head %d tail %d", rxkring->nr_hwcur, rxkring->nr_hwtail, rxkring->rcur, rxkring->rhead, rxkring->rtail); mb(); /* paired with the first mb() in txsync */ if (oldhwcur != rxkring->nr_hwcur) { /* we have released some slots, notify the other end */ mb(); /* make sure nr_hwcur is updated before notifying */ txkring->nm_notify(txkring, 0); } return 0; } /* Pipe endpoints are created and destroyed together, so that endopoints do not * have to check for the existence of their peer at each ?xsync. * * To play well with the existing netmap infrastructure (refcounts etc.), we * adopt the following strategy: * * 1) The first endpoint that is created also creates the other endpoint and * grabs a reference to it. * * state A) user1 --> endpoint1 --> endpoint2 * * 2) If, starting from state A, endpoint2 is then registered, endpoint1 gives * its reference to the user: * * state B) user1 --> endpoint1 endpoint2 <--- user2 * * 3) Assume that, starting from state B endpoint2 is closed. In the unregister * callback endpoint2 notes that endpoint1 is still active and adds a reference * from endpoint1 to itself. When user2 then releases her own reference, * endpoint2 is not destroyed and we are back to state A. A symmetrical state * would be reached if endpoint1 were released instead. * * 4) If, starting from state A, endpoint1 is closed, the destructor notes that * it owns a reference to endpoint2 and releases it. * * Something similar goes on for the creation and destruction of the krings. */ /* netmap_pipe_krings_create. * * There are two cases: * * 1) state is * * usr1 --> e1 --> e2 * * and we are e1. We have to create both sets * of krings. * * 2) state is * * usr1 --> e1 --> e2 * * and we are e2. e1 is certainly registered and our * krings already exist. Nothing to do. */ static int netmap_pipe_krings_create(struct netmap_adapter *na) { struct netmap_pipe_adapter *pna = (struct netmap_pipe_adapter *)na; struct netmap_adapter *ona = &pna->peer->up; int error = 0; enum txrx t; if (pna->peer_ref) { int i; /* case 1) above */ ND("%p: case 1, create both ends", na); error = netmap_krings_create(na, 0); if (error) goto err; /* create the krings of the other end */ error = netmap_krings_create(ona, 0); if (error) goto del_krings1; /* cross link the krings */ for_rx_tx(t) { enum txrx r = nm_txrx_swap(t); /* swap NR_TX <-> NR_RX */ for (i = 0; i < nma_get_nrings(na, t); i++) { NMR(na, t)[i].pipe = NMR(ona, r) + i; NMR(ona, r)[i].pipe = NMR(na, t) + i; } } } return 0; del_krings1: netmap_krings_delete(na); err: return error; } /* netmap_pipe_reg. * * There are two cases on registration (onoff==1) * * 1.a) state is * * usr1 --> e1 --> e2 * * and we are e1. Create the needed rings of the * other end. * * 1.b) state is * * usr1 --> e1 --> e2 <-- usr2 * * and we are e2. Drop the ref e1 is holding. * * There are two additional cases on unregister (onoff==0) * * 2.a) state is * * usr1 --> e1 --> e2 * * and we are e1. Nothing special to do, e2 will * be cleaned up by the destructor of e1. * * 2.b) state is * * usr1 --> e1 e2 <-- usr2 * * and we are either e1 or e2. Add a ref from the * other end and hide our rings. */ static int netmap_pipe_reg(struct netmap_adapter *na, int onoff) { struct netmap_pipe_adapter *pna = (struct netmap_pipe_adapter *)na; struct netmap_adapter *ona = &pna->peer->up; int i, error = 0; enum txrx t; ND("%p: onoff %d", na, onoff); if (onoff) { for_rx_tx(t) { for (i = 0; i < nma_get_nrings(na, t); i++) { struct netmap_kring *kring = &NMR(na, t)[i]; if (nm_kring_pending_on(kring)) { /* mark the peer ring as needed */ kring->pipe->nr_kflags |= NKR_NEEDRING; } } } /* create all missing needed rings on the other end */ error = netmap_mem_rings_create(ona); if (error) return error; /* In case of no error we put our rings in netmap mode */ for_rx_tx(t) { for (i = 0; i < nma_get_nrings(na, t) + 1; i++) { struct netmap_kring *kring = &NMR(na, t)[i]; if (nm_kring_pending_on(kring)) { kring->nr_mode = NKR_NETMAP_ON; } } } if (na->active_fds == 0) na->na_flags |= NAF_NETMAP_ON; } else { if (na->active_fds == 0) na->na_flags &= ~NAF_NETMAP_ON; for_rx_tx(t) { for (i = 0; i < nma_get_nrings(na, t) + 1; i++) { struct netmap_kring *kring = &NMR(na, t)[i]; if (nm_kring_pending_off(kring)) { kring->nr_mode = NKR_NETMAP_OFF; /* mark the peer ring as no longer needed by us * (it may still be kept if sombody else is using it) */ if (kring->pipe) { kring->pipe->nr_kflags &= ~NKR_NEEDRING; } } } } /* delete all the peer rings that are no longer needed */ netmap_mem_rings_delete(ona); } if (na->active_fds) { ND("active_fds %d", na->active_fds); return 0; } if (pna->peer_ref) { ND("%p: case 1.a or 2.a, nothing to do", na); return 0; } if (onoff) { ND("%p: case 1.b, drop peer", na); pna->peer->peer_ref = 0; netmap_adapter_put(na); } else { ND("%p: case 2.b, grab peer", na); netmap_adapter_get(na); pna->peer->peer_ref = 1; } return error; } /* netmap_pipe_krings_delete. * * There are two cases: * * 1) state is * * usr1 --> e1 --> e2 * * and we are e1 (e2 is not registered, so krings_delete cannot be * called on it); * * 2) state is * * usr1 --> e1 e2 <-- usr2 * * and we are either e1 or e2. * * In the former case we have to also delete the krings of e2; * in the latter case we do nothing (note that our krings * have already been hidden in the unregister callback). */ static void netmap_pipe_krings_delete(struct netmap_adapter *na) { struct netmap_pipe_adapter *pna = (struct netmap_pipe_adapter *)na; struct netmap_adapter *ona; /* na of the other end */ if (!pna->peer_ref) { ND("%p: case 2, kept alive by peer", na); return; } /* case 1) above */ ND("%p: case 1, deleting everything", na); netmap_krings_delete(na); /* also zeroes tx_rings etc. */ ona = &pna->peer->up; if (ona->tx_rings == NULL) { /* already deleted, we must be on an * cleanup-after-error path */ return; } netmap_krings_delete(ona); } static void netmap_pipe_dtor(struct netmap_adapter *na) { struct netmap_pipe_adapter *pna = (struct netmap_pipe_adapter *)na; ND("%p %p", na, pna->parent_ifp); if (pna->peer_ref) { ND("%p: clean up peer", na); pna->peer_ref = 0; netmap_adapter_put(&pna->peer->up); } if (pna->role == NR_REG_PIPE_MASTER) netmap_pipe_remove(pna->parent, pna); if (pna->parent_ifp) if_rele(pna->parent_ifp); netmap_adapter_put(pna->parent); pna->parent = NULL; } int netmap_get_pipe_na(struct nmreq *nmr, struct netmap_adapter **na, struct netmap_mem_d *nmd, int create) { struct nmreq pnmr; struct netmap_adapter *pna; /* parent adapter */ struct netmap_pipe_adapter *mna, *sna, *req; struct ifnet *ifp = NULL; u_int pipe_id; int role = nmr->nr_flags & NR_REG_MASK; int error, retries = 0; ND("flags %x", nmr->nr_flags); if (role != NR_REG_PIPE_MASTER && role != NR_REG_PIPE_SLAVE) { ND("not a pipe"); return 0; } role = nmr->nr_flags & NR_REG_MASK; /* first, try to find the parent adapter */ bzero(&pnmr, sizeof(pnmr)); memcpy(&pnmr.nr_name, nmr->nr_name, IFNAMSIZ); /* pass to parent the requested number of pipes */ pnmr.nr_arg1 = nmr->nr_arg1; for (;;) { int create_error; error = netmap_get_na(&pnmr, &pna, &ifp, nmd, create); if (!error) break; if (error != ENXIO || retries++) { ND("parent lookup failed: %d", error); return error; } ND("try to create a persistent vale port"); /* create a persistent vale port and try again */ NMG_UNLOCK(); create_error = netmap_vi_create(&pnmr, 1 /* autodelete */); NMG_LOCK(); if (create_error && create_error != EEXIST) { if (create_error != EOPNOTSUPP) { D("failed to create a persistent vale port: %d", create_error); } return error; } } if (NETMAP_OWNED_BY_KERN(pna)) { ND("parent busy"); error = EBUSY; goto put_out; } /* next, lookup the pipe id in the parent list */ req = NULL; pipe_id = nmr->nr_ringid & NETMAP_RING_MASK; mna = netmap_pipe_find(pna, pipe_id); if (mna) { if (mna->role == role) { ND("found %d directly at %d", pipe_id, mna->parent_slot); req = mna; } else { ND("found %d indirectly at %d", pipe_id, mna->parent_slot); req = mna->peer; } /* the pipe we have found already holds a ref to the parent, * so we need to drop the one we got from netmap_get_na() */ netmap_unget_na(pna, ifp); goto found; } ND("pipe %d not found, create %d", pipe_id, create); if (!create) { error = ENODEV; goto put_out; } /* we create both master and slave. * The endpoint we were asked for holds a reference to * the other one. */ mna = nm_os_malloc(sizeof(*mna)); if (mna == NULL) { error = ENOMEM; goto put_out; } snprintf(mna->up.name, sizeof(mna->up.name), "%s{%d", pna->name, pipe_id); mna->id = pipe_id; mna->role = NR_REG_PIPE_MASTER; mna->parent = pna; mna->parent_ifp = ifp; mna->up.nm_txsync = netmap_pipe_txsync; mna->up.nm_rxsync = netmap_pipe_rxsync; mna->up.nm_register = netmap_pipe_reg; mna->up.nm_dtor = netmap_pipe_dtor; mna->up.nm_krings_create = netmap_pipe_krings_create; mna->up.nm_krings_delete = netmap_pipe_krings_delete; mna->up.nm_mem = netmap_mem_get(pna->nm_mem); mna->up.na_flags |= NAF_MEM_OWNER; mna->up.na_lut = pna->na_lut; mna->up.num_tx_rings = 1; mna->up.num_rx_rings = 1; mna->up.num_tx_desc = nmr->nr_tx_slots; nm_bound_var(&mna->up.num_tx_desc, pna->num_tx_desc, 1, NM_PIPE_MAXSLOTS, NULL); mna->up.num_rx_desc = nmr->nr_rx_slots; nm_bound_var(&mna->up.num_rx_desc, pna->num_rx_desc, 1, NM_PIPE_MAXSLOTS, NULL); error = netmap_attach_common(&mna->up); if (error) goto free_mna; /* register the master with the parent */ error = netmap_pipe_add(pna, mna); if (error) goto free_mna; /* create the slave */ sna = nm_os_malloc(sizeof(*mna)); if (sna == NULL) { error = ENOMEM; goto unregister_mna; } /* most fields are the same, copy from master and then fix */ *sna = *mna; sna->up.nm_mem = netmap_mem_get(mna->up.nm_mem); snprintf(sna->up.name, sizeof(sna->up.name), "%s}%d", pna->name, pipe_id); sna->role = NR_REG_PIPE_SLAVE; error = netmap_attach_common(&sna->up); if (error) goto free_sna; /* join the two endpoints */ mna->peer = sna; sna->peer = mna; /* we already have a reference to the parent, but we * need another one for the other endpoint we created */ netmap_adapter_get(pna); /* likewise for the ifp, if any */ if (ifp) if_ref(ifp); if (role == NR_REG_PIPE_MASTER) { req = mna; mna->peer_ref = 1; netmap_adapter_get(&sna->up); } else { req = sna; sna->peer_ref = 1; netmap_adapter_get(&mna->up); } ND("created master %p and slave %p", mna, sna); found: ND("pipe %d %s at %p", pipe_id, (req->role == NR_REG_PIPE_MASTER ? "master" : "slave"), req); *na = &req->up; netmap_adapter_get(*na); /* keep the reference to the parent. * It will be released by the req destructor */ return 0; free_sna: nm_os_free(sna); unregister_mna: netmap_pipe_remove(pna, mna); free_mna: nm_os_free(mna); put_out: netmap_unget_na(pna, ifp); return error; } #endif /* WITH_PIPES */