The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netinet/toecore.c

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    1 /*-
    2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
    3  *
    4  * Copyright (c) 2012 Chelsio Communications, Inc.
    5  * All rights reserved.
    6  * Written by: Navdeep Parhar <np@FreeBSD.org>
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27  * SUCH DAMAGE.
   28  */
   29 
   30 #include <sys/cdefs.h>
   31 __FBSDID("$FreeBSD: releng/12.0/sys/netinet/toecore.c 337932 2018-08-16 23:46:38Z np $");
   32 
   33 #include "opt_inet.h"
   34 #include "opt_inet6.h"
   35 
   36 #include <sys/param.h>
   37 #include <sys/kernel.h>
   38 #include <sys/systm.h>
   39 #include <sys/malloc.h>
   40 #include <sys/mbuf.h>
   41 #include <sys/module.h>
   42 #include <sys/types.h>
   43 #include <sys/sockopt.h>
   44 #include <sys/sysctl.h>
   45 #include <sys/socket.h>
   46 
   47 #include <net/ethernet.h>
   48 #include <net/if.h>
   49 #include <net/if_var.h>
   50 #include <net/if_types.h>
   51 #include <net/if_vlan_var.h>
   52 #include <net/if_llatbl.h>
   53 #include <net/route.h>
   54 
   55 #include <netinet/if_ether.h>
   56 #include <netinet/in.h>
   57 #include <netinet/in_pcb.h>
   58 #include <netinet/in_var.h>
   59 #include <netinet6/in6_var.h>
   60 #include <netinet6/in6_pcb.h>
   61 #include <netinet6/nd6.h>
   62 #define TCPSTATES
   63 #include <netinet/tcp.h>
   64 #include <netinet/tcp_fsm.h>
   65 #include <netinet/tcp_timer.h>
   66 #include <netinet/tcp_var.h>
   67 #include <netinet/tcp_syncache.h>
   68 #include <netinet/tcp_offload.h>
   69 #include <netinet/toecore.h>
   70 
   71 static struct mtx toedev_lock;
   72 static TAILQ_HEAD(, toedev) toedev_list;
   73 static eventhandler_tag listen_start_eh;
   74 static eventhandler_tag listen_stop_eh;
   75 static eventhandler_tag lle_event_eh;
   76 
   77 static int
   78 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
   79     struct rtentry *rt __unused, struct sockaddr *nam __unused)
   80 {
   81 
   82         return (ENOTSUP);
   83 }
   84 
   85 static int
   86 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
   87 {
   88 
   89         return (ENOTSUP);
   90 }
   91 
   92 static int
   93 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
   94 {
   95 
   96         return (ENOTSUP);
   97 }
   98 
   99 static void
  100 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
  101     struct mbuf *m)
  102 {
  103 
  104         m_freem(m);
  105         return;
  106 }
  107 
  108 static void
  109 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
  110 {
  111 
  112         return;
  113 }
  114 
  115 static int
  116 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
  117 {
  118 
  119         return (ENOTSUP);
  120 }
  121 
  122 static void
  123 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
  124 {
  125 
  126         return;
  127 }
  128 
  129 static void
  130 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
  131     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
  132     uint16_t vtag __unused)
  133 {
  134 
  135         return;
  136 }
  137 
  138 static void
  139 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
  140     struct rtentry *rt0 __unused, struct rtentry *rt1 __unused)
  141 {
  142 
  143         return;
  144 }
  145 
  146 static void
  147 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
  148 {
  149 
  150         return;
  151 }
  152 
  153 static void
  154 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
  155 {
  156 
  157         return;
  158 }
  159 
  160 static int
  161 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
  162     struct mbuf *m)
  163 {
  164 
  165         m_freem(m);
  166         return (0);
  167 }
  168 
  169 static void
  170 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
  171     struct socket *so __unused)
  172 {
  173 
  174         return;
  175 }
  176 
  177 static void
  178 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
  179     int sopt_dir __unused, int sopt_name __unused)
  180 {
  181 
  182         return;
  183 }
  184 
  185 static void
  186 toedev_tcp_info(struct toedev *tod __unused, struct tcpcb *tp __unused,
  187     struct tcp_info *ti __unused)
  188 {
  189 
  190         return;
  191 }
  192 
  193 /*
  194  * Inform one or more TOE devices about a listening socket.
  195  */
  196 static void
  197 toe_listen_start(struct inpcb *inp, void *arg)
  198 {
  199         struct toedev *t, *tod;
  200         struct tcpcb *tp;
  201 
  202         INP_WLOCK_ASSERT(inp);
  203         KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
  204             ("%s: inp is not a TCP inp", __func__));
  205 
  206         if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
  207                 return;
  208 
  209         tp = intotcpcb(inp);
  210         if (tp->t_state != TCPS_LISTEN)
  211                 return;
  212 
  213         t = arg;
  214         mtx_lock(&toedev_lock);
  215         TAILQ_FOREACH(tod, &toedev_list, link) {
  216                 if (t == NULL || t == tod)
  217                         tod->tod_listen_start(tod, tp);
  218         }
  219         mtx_unlock(&toedev_lock);
  220 }
  221 
  222 static void
  223 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
  224 {
  225         struct inpcb *inp = tp->t_inpcb;
  226 
  227         INP_WLOCK_ASSERT(inp);
  228         KASSERT(tp->t_state == TCPS_LISTEN,
  229             ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
  230 
  231         toe_listen_start(inp, NULL);
  232 }
  233 
  234 static void
  235 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
  236 {
  237         struct toedev *tod;
  238 #ifdef INVARIANTS
  239         struct inpcb *inp = tp->t_inpcb;
  240 #endif
  241 
  242         INP_WLOCK_ASSERT(inp);
  243         KASSERT(tp->t_state == TCPS_LISTEN,
  244             ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
  245 
  246         mtx_lock(&toedev_lock);
  247         TAILQ_FOREACH(tod, &toedev_list, link)
  248             tod->tod_listen_stop(tod, tp);
  249         mtx_unlock(&toedev_lock);
  250 }
  251 
  252 /*
  253  * Fill up a freshly allocated toedev struct with reasonable defaults.
  254  */
  255 void
  256 init_toedev(struct toedev *tod)
  257 {
  258 
  259         tod->tod_softc = NULL;
  260 
  261         /*
  262          * Provide no-op defaults so that the kernel can call any toedev
  263          * function without having to check whether the TOE driver supplied one
  264          * or not.
  265          */
  266         tod->tod_connect = toedev_connect;
  267         tod->tod_listen_start = toedev_listen_start;
  268         tod->tod_listen_stop = toedev_listen_stop;
  269         tod->tod_input = toedev_input;
  270         tod->tod_rcvd = toedev_rcvd;
  271         tod->tod_output = toedev_output;
  272         tod->tod_send_rst = toedev_output;
  273         tod->tod_send_fin = toedev_output;
  274         tod->tod_pcb_detach = toedev_pcb_detach;
  275         tod->tod_l2_update = toedev_l2_update;
  276         tod->tod_route_redirect = toedev_route_redirect;
  277         tod->tod_syncache_added = toedev_syncache_added;
  278         tod->tod_syncache_removed = toedev_syncache_removed;
  279         tod->tod_syncache_respond = toedev_syncache_respond;
  280         tod->tod_offload_socket = toedev_offload_socket;
  281         tod->tod_ctloutput = toedev_ctloutput;
  282         tod->tod_tcp_info = toedev_tcp_info;
  283 }
  284 
  285 /*
  286  * Register an active TOE device with the system.  This allows it to receive
  287  * notifications from the kernel.
  288  */
  289 int
  290 register_toedev(struct toedev *tod)
  291 {
  292         struct toedev *t;
  293 
  294         mtx_lock(&toedev_lock);
  295         TAILQ_FOREACH(t, &toedev_list, link) {
  296                 if (t == tod) {
  297                         mtx_unlock(&toedev_lock);
  298                         return (EEXIST);
  299                 }
  300         }
  301 
  302         TAILQ_INSERT_TAIL(&toedev_list, tod, link);
  303         registered_toedevs++;
  304         mtx_unlock(&toedev_lock);
  305 
  306         inp_apply_all(toe_listen_start, tod);
  307 
  308         return (0);
  309 }
  310 
  311 /*
  312  * Remove the TOE device from the global list of active TOE devices.  It is the
  313  * caller's responsibility to ensure that the TOE device is quiesced prior to
  314  * this call.
  315  */
  316 int
  317 unregister_toedev(struct toedev *tod)
  318 {
  319         struct toedev *t, *t2;
  320         int rc = ENODEV;
  321 
  322         mtx_lock(&toedev_lock);
  323         TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
  324                 if (t == tod) {
  325                         TAILQ_REMOVE(&toedev_list, tod, link);
  326                         registered_toedevs--;
  327                         rc = 0;
  328                         break;
  329                 }
  330         }
  331         KASSERT(registered_toedevs >= 0,
  332             ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
  333         mtx_unlock(&toedev_lock);
  334         return (rc);
  335 }
  336 
  337 void
  338 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
  339     struct inpcb *inp, void *tod, void *todctx)
  340 {
  341         struct socket *lso = inp->inp_socket;
  342 
  343         INP_WLOCK_ASSERT(inp);
  344 
  345         syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx);
  346 }
  347 
  348 int
  349 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
  350     struct tcphdr *th, struct socket **lsop)
  351 {
  352 
  353         INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
  354 
  355         return (syncache_expand(inc, to, th, lsop, NULL));
  356 }
  357 
  358 /*
  359  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
  360  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
  361  * in TIME_WAIT may be assassinated freeing it up for re-use.
  362  *
  363  * Note that the TCP header must have been run through tcp_fields_to_host() or
  364  * equivalent.
  365  */
  366 int
  367 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
  368 {
  369         struct inpcb *inp;
  370 
  371         if (inc->inc_flags & INC_ISIPV6) {
  372                 inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
  373                     inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
  374                     INPLOOKUP_WLOCKPCB, ifp);
  375         } else {
  376                 inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
  377                     inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
  378         }
  379         if (inp != NULL) {
  380                 INP_WLOCK_ASSERT(inp);
  381 
  382                 if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
  383 
  384                         INP_INFO_RLOCK_ASSERT(&V_tcbinfo); /* for twcheck */
  385                         if (!tcp_twcheck(inp, NULL, th, NULL, 0))
  386                                 return (EADDRINUSE);
  387                 } else {
  388                         INP_WUNLOCK(inp);
  389                         return (EADDRINUSE);
  390                 }
  391         }
  392 
  393         return (0);
  394 }
  395 
  396 static void
  397 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
  398 {
  399         struct toedev *tod;
  400         struct ifnet *ifp;
  401         struct sockaddr *sa;
  402         uint8_t *lladdr;
  403         uint16_t vid, pcp;
  404         int family;
  405         struct sockaddr_in6 sin6;
  406 
  407         LLE_WLOCK_ASSERT(lle);
  408 
  409         ifp = lltable_get_ifp(lle->lle_tbl);
  410         family = lltable_get_af(lle->lle_tbl);
  411 
  412         if (family != AF_INET && family != AF_INET6)
  413                 return;
  414         /*
  415          * Not interested if the interface's TOE capability is not enabled.
  416          */
  417         if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
  418             (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
  419                 return;
  420 
  421         tod = TOEDEV(ifp);
  422         if (tod == NULL)
  423                 return;
  424 
  425         sa = (struct sockaddr *)&sin6;
  426         lltable_fill_sa_entry(lle, sa);
  427 
  428         vid = 0xfff;
  429         pcp = 0;
  430         if (evt != LLENTRY_RESOLVED) {
  431 
  432                 /*
  433                  * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
  434                  * this entry is going to be deleted.
  435                  */
  436 
  437                 lladdr = NULL;
  438         } else {
  439 
  440                 KASSERT(lle->la_flags & LLE_VALID,
  441                     ("%s: %p resolved but not valid?", __func__, lle));
  442 
  443                 lladdr = (uint8_t *)lle->ll_addr;
  444                 VLAN_TAG(ifp, &vid);
  445                 VLAN_PCP(ifp, &pcp);
  446         }
  447 
  448         tod->tod_l2_update(tod, ifp, sa, lladdr, EVL_MAKETAG(vid, pcp, 0));
  449 }
  450 
  451 /*
  452  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
  453  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
  454  * tod_l2_update will be called later, when the entry is resolved or times out.
  455  */
  456 int
  457 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
  458     uint8_t *lladdr, uint16_t *vtag)
  459 {
  460         int rc;
  461         uint16_t vid, pcp;
  462 
  463         switch (sa->sa_family) {
  464 #ifdef INET
  465         case AF_INET:
  466                 rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
  467                 break;
  468 #endif
  469 #ifdef INET6
  470         case AF_INET6:
  471                 rc = nd6_resolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
  472                 break;
  473 #endif
  474         default:
  475                 return (EPROTONOSUPPORT);
  476         }
  477 
  478         if (rc == 0) {
  479                 vid = 0xfff;
  480                 pcp = 0;
  481                 if (ifp->if_type == IFT_L2VLAN) {
  482                         VLAN_TAG(ifp, &vid);
  483                         VLAN_PCP(ifp, &pcp);
  484                 } else if (ifp->if_pcp != IFNET_PCP_NONE) {
  485                         vid = 0;
  486                         pcp = ifp->if_pcp;
  487                 }
  488                 *vtag = EVL_MAKETAG(vid, pcp, 0);
  489         }
  490 
  491         return (rc);
  492 }
  493 
  494 void
  495 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
  496 {
  497 
  498         INP_WLOCK_ASSERT(inp);
  499 
  500         if (!(inp->inp_flags & INP_DROPPED)) {
  501                 struct tcpcb *tp = intotcpcb(inp);
  502 
  503                 KASSERT(tp->t_flags & TF_TOE,
  504                     ("%s: tp %p not offloaded.", __func__, tp));
  505 
  506                 if (err == EAGAIN) {
  507 
  508                         /*
  509                          * Temporary failure during offload, take this PCB back.
  510                          * Detach from the TOE driver and do the rest of what
  511                          * TCP's pru_connect would have done if the connection
  512                          * wasn't offloaded.
  513                          */
  514 
  515                         tod->tod_pcb_detach(tod, tp);
  516                         KASSERT(!(tp->t_flags & TF_TOE),
  517                             ("%s: tp %p still offloaded.", __func__, tp));
  518                         tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
  519                         (void) tp->t_fb->tfb_tcp_output(tp);
  520                 } else {
  521 
  522                         INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
  523                         tp = tcp_drop(tp, err);
  524                         if (tp == NULL)
  525                                 INP_WLOCK(inp); /* re-acquire */
  526                 }
  527         }
  528         INP_WLOCK_ASSERT(inp);
  529 }
  530 
  531 static int
  532 toecore_load(void)
  533 {
  534 
  535         mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
  536         TAILQ_INIT(&toedev_list);
  537 
  538         listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
  539             toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
  540         listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
  541             toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
  542         lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
  543             EVENTHANDLER_PRI_ANY);
  544 
  545         return (0);
  546 }
  547 
  548 static int
  549 toecore_unload(void)
  550 {
  551 
  552         mtx_lock(&toedev_lock);
  553         if (!TAILQ_EMPTY(&toedev_list)) {
  554                 mtx_unlock(&toedev_lock);
  555                 return (EBUSY);
  556         }
  557 
  558         EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
  559         EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
  560         EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
  561 
  562         mtx_unlock(&toedev_lock);
  563         mtx_destroy(&toedev_lock);
  564 
  565         return (0);
  566 }
  567 
  568 static int
  569 toecore_mod_handler(module_t mod, int cmd, void *arg)
  570 {
  571 
  572         if (cmd == MOD_LOAD)
  573                 return (toecore_load());
  574 
  575         if (cmd == MOD_UNLOAD)
  576                 return (toecore_unload());
  577 
  578         return (EOPNOTSUPP);
  579 }
  580 
  581 static moduledata_t mod_data= {
  582         "toecore",
  583         toecore_mod_handler,
  584         0
  585 };
  586 
  587 MODULE_VERSION(toecore, 1);
  588 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);

Cache object: 3932d059072c820f2a0473afa7fe65e0


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