FreeBSD/Linux Kernel Cross Reference
sys/kern/uipc_msg.c

     /*
      * Copyright (c) 2003, 2004 Jeffrey M. Hsu.  All rights reserved.
      * Copyright (c) 2003, 2004 The DragonFly Project.  All rights reserved.
      * 
      * This code is derived from software contributed to The DragonFly Project
      * by Jeffrey M. Hsu.
      * 
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. Neither the name of The DragonFly Project nor the names of its
     *    contributors may be used to endorse or promote products derived
     *    from this software without specific, prior written permission.
     * 
     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
     * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
     * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
     * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
     * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     */
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/kernel.h>
    #include <sys/msgport.h>
    #include <sys/protosw.h>
    #include <sys/socket.h>
    #include <sys/socketvar.h>
    #include <sys/socketops.h>
    #include <sys/thread.h>
    #include <sys/thread2.h>
    #include <sys/msgport2.h>
    #include <sys/spinlock2.h>
    #include <sys/sysctl.h>
    #include <sys/mbuf.h>
    #include <vm/pmap.h>
    
    #include <net/netmsg2.h>
    #include <sys/socketvar2.h>
    
    #include <net/netisr.h>
    #include <net/netmsg.h>
    
    static int async_rcvd_drop_race = 0;
    SYSCTL_INT(_kern_ipc, OID_AUTO, async_rcvd_drop_race, CTLFLAG_RW,
        &async_rcvd_drop_race, 0, "# of asynchronized pru_rcvd msg drop races");
    
    /*
     * Abort a socket and free it.  Called from soabort() only.  soabort()
     * got a ref on the socket which we must free on reply.
     */
    void
    so_pru_abort(struct socket *so)
    {
            struct netmsg_pru_abort msg;
    
            netmsg_init(&msg.base, so, &curthread->td_msgport,
                        0, so->so_proto->pr_usrreqs->pru_abort);
            (void)lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
            sofree(msg.base.nm_so);
    }
    
    /*
     * Abort a socket and free it, asynchronously.  Called from
     * soaborta() only.  soaborta() got a ref on the socket which we must
     * free on reply.
     */
    void
    so_pru_aborta(struct socket *so)
    {
            struct netmsg_pru_abort *msg;
    
            msg = kmalloc(sizeof(*msg), M_LWKTMSG, M_WAITOK | M_ZERO);
            netmsg_init(&msg->base, so, &netisr_afree_free_so_rport,
                        0, so->so_proto->pr_usrreqs->pru_abort);
            lwkt_sendmsg(so->so_port, &msg->base.lmsg);
    }
    
    /*
     * Abort a socket and free it.  Called from soabort_oncpu() only.
     * Caller must make sure that the current CPU is inpcb's owner CPU.
     */
    void
    so_pru_abort_oncpu(struct socket *so)
    {
            struct netmsg_pru_abort msg;
            netisr_fn_t func = so->so_proto->pr_usrreqs->pru_abort;
   
           netmsg_init(&msg.base, so, &netisr_adone_rport, 0, func);
           msg.base.lmsg.ms_flags &= ~(MSGF_REPLY | MSGF_DONE);
           msg.base.lmsg.ms_flags |= MSGF_SYNC;
           func((netmsg_t)&msg);
           KKASSERT(msg.base.lmsg.ms_flags & MSGF_DONE);
           sofree(msg.base.nm_so);
   }
   
   int
   so_pru_accept(struct socket *so, struct sockaddr **nam)
   {
           struct netmsg_pru_accept msg;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
               0, so->so_proto->pr_usrreqs->pru_accept);
           msg.nm_nam = nam;
   
           return lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
   }
   
   int
   so_pru_attach(struct socket *so, int proto, struct pru_attach_info *ai)
   {
           struct netmsg_pru_attach msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_attach);
           msg.nm_proto = proto;
           msg.nm_ai = ai;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_attach_direct(struct socket *so, int proto, struct pru_attach_info *ai)
   {
           struct netmsg_pru_attach msg;
           netisr_fn_t func = so->so_proto->pr_usrreqs->pru_attach;
   
           netmsg_init(&msg.base, so, &netisr_adone_rport, 0, func);
           msg.base.lmsg.ms_flags &= ~(MSGF_REPLY | MSGF_DONE);
           msg.base.lmsg.ms_flags |= MSGF_SYNC;
           msg.nm_proto = proto;
           msg.nm_ai = ai;
           func((netmsg_t)&msg);
           KKASSERT(msg.base.lmsg.ms_flags & MSGF_DONE);
           return(msg.base.lmsg.ms_error);
   }
   
   /*
    * NOTE: If the target port changes the bind operation will deal with it.
    */
   int
   so_pru_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
   {
           struct netmsg_pru_bind msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_bind);
           msg.nm_nam = nam;
           msg.nm_td = td;         /* used only for prison_ip() */
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
   {
           struct netmsg_pru_connect msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_connect);
           msg.nm_nam = nam;
           msg.nm_td = td;
           msg.nm_m = NULL;
           msg.nm_sndflags = 0;
           msg.nm_flags = 0;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_connect_async(struct socket *so, struct sockaddr *nam, struct thread *td)
   {
           struct netmsg_pru_connect *msg;
           int error, flags;
   
           KASSERT(so->so_proto->pr_usrreqs->pru_preconnect != NULL,
               ("async pru_connect is not supported"));
   
           /* NOTE: sockaddr immediately follows netmsg */
           msg = kmalloc(sizeof(*msg) + nam->sa_len, M_LWKTMSG, M_NOWAIT);
           if (msg == NULL) {
                   /*
                    * Fail to allocate address w/o waiting;
                    * fallback to synchronized pru_connect.
                    */
                   return so_pru_connect(so, nam, td);
           }
   
           error = so->so_proto->pr_usrreqs->pru_preconnect(so, nam, td);
           if (error) {
                   kfree(msg, M_LWKTMSG);
                   return error;
           }
   
           flags = PRUC_ASYNC;
           if (td != NULL && (so->so_proto->pr_flags & PR_ACONN_HOLDTD)) {
                   lwkt_hold(td);
                   flags |= PRUC_HELDTD;
           }
   
           netmsg_init(&msg->base, so, &netisr_afree_rport, 0,
               so->so_proto->pr_usrreqs->pru_connect);
           msg->nm_nam = (struct sockaddr *)(msg + 1);
           memcpy(msg->nm_nam, nam, nam->sa_len);
           msg->nm_td = td;
           msg->nm_m = NULL;
           msg->nm_sndflags = 0;
           msg->nm_flags = flags;
           lwkt_sendmsg(so->so_port, &msg->base.lmsg);
           return 0;
   }
   
   int
   so_pru_connect2(struct socket *so1, struct socket *so2)
   {
           struct netmsg_pru_connect2 msg;
           int error;
   
           netmsg_init(&msg.base, so1, &curthread->td_msgport,
                       0, so1->so_proto->pr_usrreqs->pru_connect2);
           msg.nm_so1 = so1;
           msg.nm_so2 = so2;
           error = lwkt_domsg(so1->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   /*
    * WARNING!  Synchronous call from user context.  Control function may do
    *           copyin/copyout.
    */
   int
   so_pru_control_direct(struct socket *so, u_long cmd, caddr_t data,
                         struct ifnet *ifp)
   {
           struct netmsg_pru_control msg;
           netisr_fn_t func = so->so_proto->pr_usrreqs->pru_control;
   
           netmsg_init(&msg.base, so, &netisr_adone_rport, 0, func);
           msg.base.lmsg.ms_flags &= ~(MSGF_REPLY | MSGF_DONE);
           msg.base.lmsg.ms_flags |= MSGF_SYNC;
           msg.nm_cmd = cmd;
           msg.nm_data = data;
           msg.nm_ifp = ifp;
           msg.nm_td = curthread;
           func((netmsg_t)&msg);
           KKASSERT(msg.base.lmsg.ms_flags & MSGF_DONE);
           return(msg.base.lmsg.ms_error);
   }
   
   int
   so_pru_detach(struct socket *so)
   {
           struct netmsg_pru_detach msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_detach);
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   void
   so_pru_detach_direct(struct socket *so)
   {
           struct netmsg_pru_detach msg;
           netisr_fn_t func = so->so_proto->pr_usrreqs->pru_detach;
   
           netmsg_init(&msg.base, so, &netisr_adone_rport, 0, func);
           msg.base.lmsg.ms_flags &= ~(MSGF_REPLY | MSGF_DONE);
           msg.base.lmsg.ms_flags |= MSGF_SYNC;
           func((netmsg_t)&msg);
           KKASSERT(msg.base.lmsg.ms_flags & MSGF_DONE);
   }
   
   int
   so_pru_disconnect(struct socket *so)
   {
           struct netmsg_pru_disconnect msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_disconnect);
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   void
   so_pru_disconnect_direct(struct socket *so)
   {
           struct netmsg_pru_disconnect msg;
           netisr_fn_t func = so->so_proto->pr_usrreqs->pru_disconnect;
   
           netmsg_init(&msg.base, so, &netisr_adone_rport, 0, func);
           msg.base.lmsg.ms_flags &= ~(MSGF_REPLY | MSGF_DONE);
           msg.base.lmsg.ms_flags |= MSGF_SYNC;
           func((netmsg_t)&msg);
           KKASSERT(msg.base.lmsg.ms_flags & MSGF_DONE);
   }
   
   int
   so_pru_listen(struct socket *so, struct thread *td)
   {
           struct netmsg_pru_listen msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_listen);
           msg.nm_td = td;         /* used only for prison_ip() XXX JH */
           msg.nm_flags = 0;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_peeraddr(struct socket *so, struct sockaddr **nam)
   {
           struct netmsg_pru_peeraddr msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_peeraddr);
           msg.nm_nam = nam;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_rcvd(struct socket *so, int flags)
   {
           struct netmsg_pru_rcvd msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_rcvd);
           msg.nm_flags = flags;
           msg.nm_pru_flags = 0;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   void
   so_pru_rcvd_async(struct socket *so)
   {
           lwkt_msg_t lmsg = &so->so_rcvd_msg.base.lmsg;
   
           KASSERT(so->so_proto->pr_flags & PR_ASYNC_RCVD,
               ("async pru_rcvd is not supported"));
   
           /*
            * WARNING!  Spinlock is a bit dodgy, use hacked up sendmsg
            *           to avoid deadlocking.
            */
           spin_lock(&so->so_rcvd_spin);
           if ((so->so_rcvd_msg.nm_pru_flags & PRUR_DEAD) == 0) {
                   if (lmsg->ms_flags & MSGF_DONE) {
                           lwkt_sendmsg_prepare(so->so_port, lmsg);
                           spin_unlock(&so->so_rcvd_spin);
                           lwkt_sendmsg_start(so->so_port, lmsg);
                   } else {
                           spin_unlock(&so->so_rcvd_spin);
                   }
           } else {
                   spin_unlock(&so->so_rcvd_spin);
           }
   }
   
   int
   so_pru_rcvoob(struct socket *so, struct mbuf *m, int flags)
   {
           struct netmsg_pru_rcvoob msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_rcvoob);
           msg.nm_m = m;
           msg.nm_flags = flags;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   /*
    * NOTE: If the target port changes the implied connect will deal with it.
    */
   int
   so_pru_send(struct socket *so, int flags, struct mbuf *m,
               struct sockaddr *addr, struct mbuf *control, struct thread *td)
   {
           struct netmsg_pru_send msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_send);
           msg.nm_flags = flags;
           msg.nm_m = m;
           msg.nm_addr = addr;
           msg.nm_control = control;
           msg.nm_td = td;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   void
   so_pru_sync(struct socket *so)
   {
           struct netmsg_base msg;
   
           netmsg_init(&msg, so, &curthread->td_msgport, 0,
               netmsg_sync_handler);
           lwkt_domsg(so->so_port, &msg.lmsg, 0);
   }
   
   void
   so_pru_send_async(struct socket *so, int flags, struct mbuf *m,
       struct sockaddr *addr0, struct mbuf *control, struct thread *td)
   {
           struct netmsg_pru_send *msg;
           struct sockaddr *addr = NULL;
   
           KASSERT(so->so_proto->pr_flags & PR_ASYNC_SEND,
               ("async pru_send is not supported"));
   
           if (addr0 != NULL) {
                   addr = kmalloc(addr0->sa_len, M_SONAME, M_NOWAIT);
                   if (addr == NULL) {
                           /*
                            * Fail to allocate address w/o waiting;
                            * fallback to synchronized pru_send.
                            */
                           so_pru_send(so, flags, m, addr0, control, td);
                           return;
                   }
                   memcpy(addr, addr0, addr0->sa_len);
                   flags |= PRUS_FREEADDR;
           }
           flags |= PRUS_NOREPLY;
   
           if (td != NULL && (so->so_proto->pr_flags & PR_ASEND_HOLDTD)) {
                   lwkt_hold(td);
                   flags |= PRUS_HELDTD;
           }
   
           msg = &m->m_hdr.mh_sndmsg;
           netmsg_init(&msg->base, so, &netisr_apanic_rport,
                       0, so->so_proto->pr_usrreqs->pru_send);
           msg->nm_flags = flags;
           msg->nm_m = m;
           msg->nm_addr = addr;
           msg->nm_control = control;
           msg->nm_td = td;
           lwkt_sendmsg(so->so_port, &msg->base.lmsg);
   }
   
   int
   so_pru_sense(struct socket *so, struct stat *sb)
   {
           struct netmsg_pru_sense msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_sense);
           msg.nm_stat = sb;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_shutdown(struct socket *so)
   {
           struct netmsg_pru_shutdown msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_shutdown);
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pru_sockaddr(struct socket *so, struct sockaddr **nam)
   {
           struct netmsg_pru_sockaddr msg;
           int error;
   
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_usrreqs->pru_sockaddr);
           msg.nm_nam = nam;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   int
   so_pr_ctloutput(struct socket *so, struct sockopt *sopt)
   {
           struct netmsg_pr_ctloutput msg;
           int error;
   
           KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
           netmsg_init(&msg.base, so, &curthread->td_msgport,
                       0, so->so_proto->pr_ctloutput);
           msg.nm_sopt = sopt;
           error = lwkt_domsg(so->so_port, &msg.base.lmsg, 0);
           return (error);
   }
   
   /*
    * Protocol control input, typically via icmp.
    *
    * If the protocol pr_ctlport is not NULL we call it to figure out the
    * protocol port.  If NULL is returned we can just return, otherwise
    * we issue a netmsg to call pr_ctlinput in the proper thread.
    *
    * This must be done synchronously as arg and/or extra may point to
    * temporary data.
    */
   void
   so_pru_ctlinput(struct protosw *pr, int cmd, struct sockaddr *arg, void *extra)
   {
           struct netmsg_pru_ctlinput msg;
           lwkt_port_t port;
   
           if (pr->pr_ctlport == NULL)
                   return;
           KKASSERT(pr->pr_ctlinput != NULL);
           port = pr->pr_ctlport(cmd, arg, extra);
           if (port == NULL)
                   return;
           netmsg_init(&msg.base, NULL, &curthread->td_msgport,
                       0, pr->pr_ctlinput);
           msg.nm_cmd = cmd;
           msg.nm_arg = arg;
           msg.nm_extra = extra;
           lwkt_domsg(port, &msg.base.lmsg, 0);
   }
   
   /*
    * If we convert all the protosw pr_ functions for all the protocols
    * to take a message directly, this layer can go away.  For the moment
    * our dispatcher ignores the return value, but since we are handling
    * the replymsg ourselves we return EASYNC by convention.
    */
   
   /*
    * Handle a predicate event request.  This function is only called once
    * when the predicate message queueing request is received.
    */
   void
   netmsg_so_notify(netmsg_t msg)
   {
           struct lwkt_token *tok;
           struct signalsockbuf *ssb;
   
           ssb = (msg->notify.nm_etype & NM_REVENT) ?
                           &msg->base.nm_so->so_rcv :
                           &msg->base.nm_so->so_snd;
   
           /*
            * Reply immediately if the event has occured, otherwise queue the
            * request.
            *
            * NOTE: Socket can change if this is an accept predicate so cache
            *       the token.
            */
           tok = lwkt_token_pool_lookup(msg->base.nm_so);
           lwkt_gettoken(tok);
           atomic_set_int(&ssb->ssb_flags, SSB_MEVENT);
           if (msg->notify.nm_predicate(&msg->notify)) {
                   if (TAILQ_EMPTY(&ssb->ssb_kq.ki_mlist))
                           atomic_clear_int(&ssb->ssb_flags, SSB_MEVENT);
                   lwkt_reltoken(tok);
                   lwkt_replymsg(&msg->base.lmsg,
                                 msg->base.lmsg.ms_error);
           } else {
                   TAILQ_INSERT_TAIL(&ssb->ssb_kq.ki_mlist, &msg->notify, nm_list);
                   /*
                    * NOTE:
                    * If predict ever blocks, 'tok' will be released, so
                    * SSB_MEVENT set beforehand could have been cleared
                    * when we reach here.  In case that happens, we set
                    * SSB_MEVENT again, after the notify has been queued.
                    */
                   atomic_set_int(&ssb->ssb_flags, SSB_MEVENT);
                   lwkt_reltoken(tok);
           }
   }
   
   /*
    * Called by doio when trying to abort a netmsg_so_notify message.
    * Unlike the other functions this one is dispatched directly by
    * the LWKT subsystem, so it takes a lwkt_msg_t as an argument.
    *
    * The original message, lmsg, is under the control of the caller and
    * will not be destroyed until we return so we can safely reference it
    * in our synchronous abort request.
    *
    * This part of the abort request occurs on the originating cpu which
    * means we may race the message flags and the original message may
    * not even have been processed by the target cpu yet.
    */
   void
   netmsg_so_notify_doabort(lwkt_msg_t lmsg)
   {
           struct netmsg_so_notify_abort msg;
   
           if ((lmsg->ms_flags & (MSGF_DONE | MSGF_REPLY)) == 0) {
                   const struct netmsg_base *nmsg =
                       (const struct netmsg_base *)lmsg;
   
                   netmsg_init(&msg.base, nmsg->nm_so, &curthread->td_msgport,
                               0, netmsg_so_notify_abort);
                   msg.nm_notifymsg = (void *)lmsg;
                   lwkt_domsg(lmsg->ms_target_port, &msg.base.lmsg, 0);
           }
   }
   
   /*
    * Predicate requests can be aborted.  This function is only called once
    * and will interlock against processing/reply races (since such races
    * occur on the same thread that controls the port where the abort is 
    * requeued).
    *
    * This part of the abort request occurs on the target cpu.  The message
    * flags must be tested again in case the test that we did on the
    * originating cpu raced.  Since messages are handled in sequence, the
    * original message will have already been handled by the loop and either
    * replied to or queued.
    *
    * We really only need to interlock with MSGF_REPLY (a bit that is set on
    * our cpu when we reply).  Note that MSGF_DONE is not set until the
    * reply reaches the originating cpu.  Test both bits anyway.
    */
   void
   netmsg_so_notify_abort(netmsg_t msg)
   {
           struct netmsg_so_notify_abort *abrtmsg = &msg->notify_abort;
           struct netmsg_so_notify *nmsg = abrtmsg->nm_notifymsg;
           struct signalsockbuf *ssb;
   
           /*
            * The original notify message is not destroyed until after the
            * abort request is returned, so we can check its state.
            */
           lwkt_getpooltoken(nmsg->base.nm_so);
           if ((nmsg->base.lmsg.ms_flags & (MSGF_DONE | MSGF_REPLY)) == 0) {
                   ssb = (nmsg->nm_etype & NM_REVENT) ?
                                   &nmsg->base.nm_so->so_rcv :
                                   &nmsg->base.nm_so->so_snd;
                   TAILQ_REMOVE(&ssb->ssb_kq.ki_mlist, nmsg, nm_list);
                   lwkt_relpooltoken(nmsg->base.nm_so);
                   lwkt_replymsg(&nmsg->base.lmsg, EINTR);
           } else {
                   lwkt_relpooltoken(nmsg->base.nm_so);
           }
   
           /*
            * Reply to the abort message
            */
           lwkt_replymsg(&abrtmsg->base.lmsg, 0);
   }
   
   void
   so_async_rcvd_reply(struct socket *so)
   {
           /*
            * Spinlock safe, reply runs to degenerate lwkt_null_replyport()
            */
           spin_lock(&so->so_rcvd_spin);
           lwkt_replymsg(&so->so_rcvd_msg.base.lmsg, 0);
           spin_unlock(&so->so_rcvd_spin);
   }
   
   void
   so_async_rcvd_drop(struct socket *so)
   {
           lwkt_msg_t lmsg = &so->so_rcvd_msg.base.lmsg;
   
           /*
            * Spinlock safe, drop runs to degenerate lwkt_spin_dropmsg()
            */
           spin_lock(&so->so_rcvd_spin);
           so->so_rcvd_msg.nm_pru_flags |= PRUR_DEAD;
   again:
           lwkt_dropmsg(lmsg);
           if ((lmsg->ms_flags & MSGF_DONE) == 0) {
                   ++async_rcvd_drop_race;
                   ssleep(so, &so->so_rcvd_spin, 0, "soadrop", 1);
                   goto again;
           }
           spin_unlock(&so->so_rcvd_spin);
   }

Cache object: 948bd808c16e10b64eb7afeaad7a92e3