/* * Copyright (c) 1989, 1991, 1993, 1995 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Rick Macklem at The University of Guelph. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. * * @(#)nfs_socket.c 8.5 (Berkeley) 3/30/95 */ #include __FBSDID("$FreeBSD$"); /* * Socket operations for use by nfs */ #include "opt_inet6.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define TRUE 1 #define FALSE 0 /* * Estimate rto for an nfs rpc sent via. an unreliable datagram. * Use the mean and mean deviation of rtt for the appropriate type of rpc * for the frequent rpcs and a default for the others. * The justification for doing "other" this way is that these rpcs * happen so infrequently that timer est. would probably be stale. * Also, since many of these rpcs are * non-idempotent, a conservative timeout is desired. * getattr, lookup - A+2D * read, write - A+4D * other - nm_timeo */ #define NFS_RTO(n, t) \ ((t) == 0 ? (n)->nm_timeo : \ ((t) < 3 ? \ (((((n)->nm_srtt[t-1] + 3) >> 2) + (n)->nm_sdrtt[t-1] + 1) >> 1) : \ ((((n)->nm_srtt[t-1] + 7) >> 3) + (n)->nm_sdrtt[t-1] + 1))) #define NFS_SRTT(r) (r)->r_nmp->nm_srtt[proct[(r)->r_procnum] - 1] #define NFS_SDRTT(r) (r)->r_nmp->nm_sdrtt[proct[(r)->r_procnum] - 1] /* * Defines which timer to use for the procnum. * 0 - default * 1 - getattr * 2 - lookup * 3 - read * 4 - write */ static int proct[NFS_NPROCS] = { 0, 1, 0, 2, 1, 3, 3, 4, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, }; static int nfs_realign_test; static int nfs_realign_count; static int nfs_bufpackets = 4; SYSCTL_DECL(_vfs_nfs); SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_test, CTLFLAG_RW, &nfs_realign_test, 0, ""); SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_count, CTLFLAG_RW, &nfs_realign_count, 0, ""); SYSCTL_INT(_vfs_nfs, OID_AUTO, bufpackets, CTLFLAG_RW, &nfs_bufpackets, 0, ""); /* * There is a congestion window for outstanding rpcs maintained per mount * point. The cwnd size is adjusted in roughly the way that: * Van Jacobson, Congestion avoidance and Control, In "Proceedings of * SIGCOMM '88". ACM, August 1988. * describes for TCP. The cwnd size is chopped in half on a retransmit timeout * and incremented by 1/cwnd when each rpc reply is received and a full cwnd * of rpcs is in progress. * (The sent count and cwnd are scaled for integer arith.) * Variants of "slow start" were tried and were found to be too much of a * performance hit (ave. rtt 3 times larger), * I suspect due to the large rtt that nfs rpcs have. */ #define NFS_CWNDSCALE 256 #define NFS_MAXCWND (NFS_CWNDSCALE * 32) #define NFS_NBACKOFF 8 static int nfs_backoff[NFS_NBACKOFF] = { 2, 4, 8, 16, 32, 64, 128, 256, }; struct callout_handle nfs_timer_handle; static int nfs_msg(struct thread *, char *, char *); static int nfs_rcvlock(struct nfsreq *); static void nfs_rcvunlock(struct nfsreq *); static void nfs_realign(struct mbuf **pm, int hsiz); static int nfs_receive(struct nfsreq *rep, struct sockaddr **aname, struct mbuf **mp); static int nfs_reply(struct nfsreq *); static void nfs_softterm(struct nfsreq *rep); static int nfs_reconnect(struct nfsreq *rep); /* * Initialize sockets and congestion for a new NFS connection. * We do not free the sockaddr if error. */ int nfs_connect(struct nfsmount *nmp, struct nfsreq *rep) { struct socket *so; int s, error, rcvreserve, sndreserve; int pktscale; struct sockaddr *saddr; struct thread *td = &thread0; /* only used for socreate and sobind */ nmp->nm_so = NULL; saddr = nmp->nm_nam; error = socreate(saddr->sa_family, &nmp->nm_so, nmp->nm_sotype, nmp->nm_soproto, nmp->nm_mountp->mnt_cred, td); if (error) goto bad; so = nmp->nm_so; nmp->nm_soflags = so->so_proto->pr_flags; /* * Some servers require that the client port be a reserved port number. */ if (nmp->nm_flag & NFSMNT_RESVPORT) { struct sockopt sopt; int ip, ip2, len; struct sockaddr_in6 ssin; struct sockaddr *sa; bzero(&sopt, sizeof sopt); switch(saddr->sa_family) { case AF_INET: sopt.sopt_level = IPPROTO_IP; sopt.sopt_name = IP_PORTRANGE; ip = IP_PORTRANGE_LOW; ip2 = IP_PORTRANGE_DEFAULT; len = sizeof (struct sockaddr_in); break; #ifdef INET6 case AF_INET6: sopt.sopt_level = IPPROTO_IPV6; sopt.sopt_name = IPV6_PORTRANGE; ip = IPV6_PORTRANGE_LOW; ip2 = IPV6_PORTRANGE_DEFAULT; len = sizeof (struct sockaddr_in6); break; #endif default: goto noresvport; } sa = (struct sockaddr *)&ssin; bzero(sa, len); sa->sa_len = len; sa->sa_family = saddr->sa_family; sopt.sopt_dir = SOPT_SET; sopt.sopt_val = (void *)&ip; sopt.sopt_valsize = sizeof(ip); error = sosetopt(so, &sopt); if (error) goto bad; error = sobind(so, sa, td); if (error) goto bad; ip = ip2; error = sosetopt(so, &sopt); if (error) goto bad; noresvport: ; } /* * Protocols that do not require connections may be optionally left * unconnected for servers that reply from a port other than NFS_PORT. */ if (nmp->nm_flag & NFSMNT_NOCONN) { if (nmp->nm_soflags & PR_CONNREQUIRED) { error = ENOTCONN; goto bad; } } else { error = soconnect(so, nmp->nm_nam, td); if (error) goto bad; /* * Wait for the connection to complete. Cribbed from the * connect system call but with the wait timing out so * that interruptible mounts don't hang here for a long time. */ s = splnet(); while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) { (void) tsleep(&so->so_timeo, PSOCK, "nfscon", 2 * hz); if ((so->so_state & SS_ISCONNECTING) && so->so_error == 0 && rep && (error = nfs_sigintr(nmp, rep, rep->r_td)) != 0) { so->so_state &= ~SS_ISCONNECTING; splx(s); goto bad; } } if (so->so_error) { error = so->so_error; so->so_error = 0; splx(s); goto bad; } splx(s); } so->so_rcv.sb_timeo = 5 * hz; so->so_snd.sb_timeo = 5 * hz; /* * Get buffer reservation size from sysctl, but impose reasonable * limits. */ pktscale = nfs_bufpackets; if (pktscale < 2) pktscale = 2; if (pktscale > 64) pktscale = 64; if (nmp->nm_sotype == SOCK_DGRAM) { sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * pktscale; rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) + NFS_MAXPKTHDR) * pktscale; } else if (nmp->nm_sotype == SOCK_SEQPACKET) { sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * pktscale; rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) + NFS_MAXPKTHDR) * pktscale; } else { if (nmp->nm_sotype != SOCK_STREAM) panic("nfscon sotype"); if (so->so_proto->pr_flags & PR_CONNREQUIRED) { struct sockopt sopt; int val; bzero(&sopt, sizeof sopt); sopt.sopt_level = SOL_SOCKET; sopt.sopt_name = SO_KEEPALIVE; sopt.sopt_val = &val; sopt.sopt_valsize = sizeof val; val = 1; sosetopt(so, &sopt); } if (so->so_proto->pr_protocol == IPPROTO_TCP) { struct sockopt sopt; int val; bzero(&sopt, sizeof sopt); sopt.sopt_level = IPPROTO_TCP; sopt.sopt_name = TCP_NODELAY; sopt.sopt_val = &val; sopt.sopt_valsize = sizeof val; val = 1; sosetopt(so, &sopt); } sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR + sizeof (u_int32_t)) * pktscale; rcvreserve = (nmp->nm_rsize + NFS_MAXPKTHDR + sizeof (u_int32_t)) * pktscale; } error = soreserve(so, sndreserve, rcvreserve); if (error) goto bad; so->so_rcv.sb_flags |= SB_NOINTR; so->so_snd.sb_flags |= SB_NOINTR; /* Initialize other non-zero congestion variables */ nmp->nm_srtt[0] = nmp->nm_srtt[1] = nmp->nm_srtt[2] = nmp->nm_srtt[3] = (NFS_TIMEO << 3); nmp->nm_sdrtt[0] = nmp->nm_sdrtt[1] = nmp->nm_sdrtt[2] = nmp->nm_sdrtt[3] = 0; nmp->nm_cwnd = NFS_MAXCWND / 2; /* Initial send window */ nmp->nm_sent = 0; nmp->nm_timeouts = 0; return (0); bad: nfs_disconnect(nmp); return (error); } /* * Reconnect routine: * Called when a connection is broken on a reliable protocol. * - clean up the old socket * - nfs_connect() again * - set R_MUSTRESEND for all outstanding requests on mount point * If this fails the mount point is DEAD! * nb: Must be called with the nfs_sndlock() set on the mount point. */ static int nfs_reconnect(struct nfsreq *rep) { struct nfsreq *rp; struct nfsmount *nmp = rep->r_nmp; int error; nfs_disconnect(nmp); while ((error = nfs_connect(nmp, rep)) != 0) { if (error == EINTR || error == ERESTART) return (EINTR); (void) tsleep(&lbolt, PSOCK, "nfscon", 0); } /* * Loop through outstanding request list and fix up all requests * on old socket. */ TAILQ_FOREACH(rp, &nfs_reqq, r_chain) { if (rp->r_nmp == nmp) rp->r_flags |= R_MUSTRESEND; } return (0); } /* * NFS disconnect. Clean up and unlink. */ void nfs_disconnect(struct nfsmount *nmp) { struct socket *so; if (nmp->nm_so) { so = nmp->nm_so; nmp->nm_so = NULL; soshutdown(so, 2); soclose(so); } } void nfs_safedisconnect(struct nfsmount *nmp) { struct nfsreq dummyreq; bzero(&dummyreq, sizeof(dummyreq)); dummyreq.r_nmp = nmp; nfs_rcvlock(&dummyreq); nfs_disconnect(nmp); nfs_rcvunlock(&dummyreq); } /* * This is the nfs send routine. For connection based socket types, it * must be called with an nfs_sndlock() on the socket. * - return EINTR if the RPC is terminated, 0 otherwise * - set R_MUSTRESEND if the send fails for any reason * - do any cleanup required by recoverable socket errors (?) */ int nfs_send(struct socket *so, struct sockaddr *nam, struct mbuf *top, struct nfsreq *rep) { struct sockaddr *sendnam; int error, soflags, flags; KASSERT(rep, ("nfs_send: called with rep == NULL")); if (rep->r_flags & R_SOFTTERM) { m_freem(top); return (EINTR); } if ((so = rep->r_nmp->nm_so) == NULL) { rep->r_flags |= R_MUSTRESEND; m_freem(top); return (0); } rep->r_flags &= ~R_MUSTRESEND; soflags = rep->r_nmp->nm_soflags; if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED)) sendnam = NULL; else sendnam = nam; if (so->so_type == SOCK_SEQPACKET) flags = MSG_EOR; else flags = 0; error = so->so_proto->pr_usrreqs->pru_sosend(so, sendnam, 0, top, 0, flags, curthread /*XXX*/); if (error == ENOBUFS && so->so_type == SOCK_DGRAM) { error = 0; rep->r_flags |= R_MUSTRESEND; } if (error) { log(LOG_INFO, "nfs send error %d for server %s\n", error, rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname); /* * Deal with errors for the client side. */ if (rep->r_flags & R_SOFTTERM) error = EINTR; else rep->r_flags |= R_MUSTRESEND; /* * Handle any recoverable (soft) socket errors here. (?) */ if (error != EINTR && error != ERESTART && error != EWOULDBLOCK && error != EPIPE) error = 0; } return (error); } /* * Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all * done by soreceive(), but for SOCK_STREAM we must deal with the Record * Mark and consolidate the data into a new mbuf list. * nb: Sometimes TCP passes the data up to soreceive() in long lists of * small mbufs. * For SOCK_STREAM we must be very careful to read an entire record once * we have read any of it, even if the system call has been interrupted. */ static int nfs_receive(struct nfsreq *rep, struct sockaddr **aname, struct mbuf **mp) { struct socket *so; struct uio auio; struct iovec aio; struct mbuf *m; struct mbuf *control; u_int32_t len; struct sockaddr **getnam; int error, sotype, rcvflg; struct thread *td = curthread; /* XXX */ /* * Set up arguments for soreceive() */ *mp = NULL; *aname = NULL; sotype = rep->r_nmp->nm_sotype; /* * For reliable protocols, lock against other senders/receivers * in case a reconnect is necessary. * For SOCK_STREAM, first get the Record Mark to find out how much * more there is to get. * We must lock the socket against other receivers * until we have an entire rpc request/reply. */ if (sotype != SOCK_DGRAM) { error = nfs_sndlock(rep); if (error) return (error); tryagain: /* * Check for fatal errors and resending request. */ /* * Ugh: If a reconnect attempt just happened, nm_so * would have changed. NULL indicates a failed * attempt that has essentially shut down this * mount point. */ if (rep->r_mrep || (rep->r_flags & R_SOFTTERM)) { nfs_sndunlock(rep); return (EINTR); } so = rep->r_nmp->nm_so; if (!so) { error = nfs_reconnect(rep); if (error) { nfs_sndunlock(rep); return (error); } goto tryagain; } while (rep->r_flags & R_MUSTRESEND) { m = m_copym(rep->r_mreq, 0, M_COPYALL, M_TRYWAIT); nfsstats.rpcretries++; error = nfs_send(so, rep->r_nmp->nm_nam, m, rep); if (error) { if (error == EINTR || error == ERESTART || (error = nfs_reconnect(rep)) != 0) { nfs_sndunlock(rep); return (error); } goto tryagain; } } nfs_sndunlock(rep); if (sotype == SOCK_STREAM) { aio.iov_base = (caddr_t) &len; aio.iov_len = sizeof(u_int32_t); auio.uio_iov = &aio; auio.uio_iovcnt = 1; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_READ; auio.uio_offset = 0; auio.uio_resid = sizeof(u_int32_t); auio.uio_td = td; do { rcvflg = MSG_WAITALL; error = so->so_proto->pr_usrreqs->pru_soreceive (so, NULL, &auio, NULL, NULL, &rcvflg); if (error == EWOULDBLOCK && rep) { if (rep->r_flags & R_SOFTTERM) return (EINTR); } } while (error == EWOULDBLOCK); if (!error && auio.uio_resid > 0) { /* * Don't log a 0 byte receive; it means * that the socket has been closed, and * can happen during normal operation * (forcible unmount or Solaris server). */ if (auio.uio_resid != sizeof (u_int32_t)) log(LOG_INFO, "short receive (%d/%d) from nfs server %s\n", (int)(sizeof(u_int32_t) - auio.uio_resid), (int)sizeof(u_int32_t), rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname); error = EPIPE; } if (error) goto errout; len = ntohl(len) & ~0x80000000; /* * This is SERIOUS! We are out of sync with the sender * and forcing a disconnect/reconnect is all I can do. */ if (len > NFS_MAXPACKET) { log(LOG_ERR, "%s (%d) from nfs server %s\n", "impossible packet length", len, rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname); error = EFBIG; goto errout; } auio.uio_resid = len; do { rcvflg = MSG_WAITALL; error = so->so_proto->pr_usrreqs->pru_soreceive (so, NULL, &auio, mp, NULL, &rcvflg); } while (error == EWOULDBLOCK || error == EINTR || error == ERESTART); if (!error && auio.uio_resid > 0) { if (len != auio.uio_resid) log(LOG_INFO, "short receive (%d/%d) from nfs server %s\n", len - auio.uio_resid, len, rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname); error = EPIPE; } } else { /* * NB: Since uio_resid is big, MSG_WAITALL is ignored * and soreceive() will return when it has either a * control msg or a data msg. * We have no use for control msg., but must grab them * and then throw them away so we know what is going * on. */ auio.uio_resid = len = 100000000; /* Anything Big */ auio.uio_td = td; do { rcvflg = 0; error = so->so_proto->pr_usrreqs->pru_soreceive (so, NULL, &auio, mp, &control, &rcvflg); if (control) m_freem(control); if (error == EWOULDBLOCK && rep) { if (rep->r_flags & R_SOFTTERM) return (EINTR); } } while (error == EWOULDBLOCK || (!error && *mp == NULL && control)); if ((rcvflg & MSG_EOR) == 0) printf("Egad!!\n"); if (!error && *mp == NULL) error = EPIPE; len -= auio.uio_resid; } errout: if (error && error != EINTR && error != ERESTART) { m_freem(*mp); *mp = NULL; if (error != EPIPE) log(LOG_INFO, "receive error %d from nfs server %s\n", error, rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname); error = nfs_sndlock(rep); if (!error) { error = nfs_reconnect(rep); if (!error) goto tryagain; else nfs_sndunlock(rep); } } } else { if ((so = rep->r_nmp->nm_so) == NULL) return (EACCES); if (so->so_state & SS_ISCONNECTED) getnam = NULL; else getnam = aname; auio.uio_resid = len = 1000000; auio.uio_td = td; do { rcvflg = 0; error = so->so_proto->pr_usrreqs->pru_soreceive (so, getnam, &auio, mp, NULL, &rcvflg); if (error == EWOULDBLOCK && (rep->r_flags & R_SOFTTERM)) return (EINTR); } while (error == EWOULDBLOCK); len -= auio.uio_resid; } if (error) { m_freem(*mp); *mp = NULL; } /* * Search for any mbufs that are not a multiple of 4 bytes long * or with m_data not longword aligned. * These could cause pointer alignment problems, so copy them to * well aligned mbufs. */ nfs_realign(mp, 5 * NFSX_UNSIGNED); return (error); } /* * Implement receipt of reply on a socket. * We must search through the list of received datagrams matching them * with outstanding requests using the xid, until ours is found. */ /* ARGSUSED */ static int nfs_reply(struct nfsreq *myrep) { struct nfsreq *rep; struct nfsmount *nmp = myrep->r_nmp; int32_t t1; struct mbuf *mrep, *md; struct sockaddr *nam; u_int32_t rxid, *tl; caddr_t dpos; int error; /* * Loop around until we get our own reply */ for (;;) { /* * Lock against other receivers so that I don't get stuck in * sbwait() after someone else has received my reply for me. * Also necessary for connection based protocols to avoid * race conditions during a reconnect. * If nfs_rcvlock() returns EALREADY, that means that * the reply has already been recieved by another * process and we can return immediately. In this * case, the lock is not taken to avoid races with * other processes. */ error = nfs_rcvlock(myrep); if (error == EALREADY) return (0); if (error) return (error); /* * Get the next Rpc reply off the socket */ error = nfs_receive(myrep, &nam, &mrep); nfs_rcvunlock(myrep); if (error) { /* * Ignore routing errors on connectionless protocols?? */ if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) { nmp->nm_so->so_error = 0; if (myrep->r_flags & R_GETONEREP) return (0); continue; } return (error); } if (nam) FREE(nam, M_SONAME); /* * Get the xid and check that it is an rpc reply */ md = mrep; dpos = mtod(md, caddr_t); tl = nfsm_dissect(u_int32_t *, 2 * NFSX_UNSIGNED); rxid = *tl++; if (*tl != rpc_reply) { nfsstats.rpcinvalid++; m_freem(mrep); nfsmout: if (myrep->r_flags & R_GETONEREP) return (0); continue; } /* * Loop through the request list to match up the reply * Iff no match, just drop the datagram */ TAILQ_FOREACH(rep, &nfs_reqq, r_chain) { if (rep->r_mrep == NULL && rxid == rep->r_xid) { /* Found it.. */ rep->r_mrep = mrep; rep->r_md = md; rep->r_dpos = dpos; /* * Update congestion window. * Do the additive increase of * one rpc/rtt. */ if (nmp->nm_cwnd <= nmp->nm_sent) { nmp->nm_cwnd += (NFS_CWNDSCALE * NFS_CWNDSCALE + (nmp->nm_cwnd >> 1)) / nmp->nm_cwnd; if (nmp->nm_cwnd > NFS_MAXCWND) nmp->nm_cwnd = NFS_MAXCWND; } if (rep->r_flags & R_SENT) { rep->r_flags &= ~R_SENT; nmp->nm_sent -= NFS_CWNDSCALE; } /* * Update rtt using a gain of 0.125 on the mean * and a gain of 0.25 on the deviation. */ if (rep->r_flags & R_TIMING) { /* * Since the timer resolution of * NFS_HZ is so course, it can often * result in r_rtt == 0. Since * r_rtt == N means that the actual * rtt is between N+dt and N+2-dt ticks, * add 1. */ t1 = rep->r_rtt + 1; t1 -= (NFS_SRTT(rep) >> 3); NFS_SRTT(rep) += t1; if (t1 < 0) t1 = -t1; t1 -= (NFS_SDRTT(rep) >> 2); NFS_SDRTT(rep) += t1; } nmp->nm_timeouts = 0; break; } } /* * If not matched to a request, drop it. * If it's mine, get out. */ if (rep == 0) { nfsstats.rpcunexpected++; m_freem(mrep); } else if (rep == myrep) { if (rep->r_mrep == NULL) panic("nfsreply nil"); return (0); } if (myrep->r_flags & R_GETONEREP) return (0); } } /* * nfs_request - goes something like this * - fill in request struct * - links it into list * - calls nfs_send() for first transmit * - calls nfs_receive() to get reply * - break down rpc header and return with nfs reply pointed to * by mrep or error * nb: always frees up mreq mbuf list */ /* XXX overloaded before */ #define NQ_TRYLATERDEL 15 /* Initial try later delay (sec) */ int nfs_request(struct vnode *vp, struct mbuf *mrest, int procnum, struct thread *td, struct ucred *cred, struct mbuf **mrp, struct mbuf **mdp, caddr_t *dposp) { struct mbuf *mrep, *m2; struct nfsreq *rep; u_int32_t *tl; int i; struct nfsmount *nmp; struct mbuf *m, *md, *mheadend; time_t waituntil; caddr_t dpos; int s, error = 0, mrest_len, auth_len, auth_type; int trylater_delay = NQ_TRYLATERDEL, trylater_cnt = 0; u_int32_t xid; /* Reject requests while attempting a forced unmount. */ if (vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF) { m_freem(mrest); return (ESTALE); } nmp = VFSTONFS(vp->v_mount); MALLOC(rep, struct nfsreq *, sizeof(struct nfsreq), M_NFSREQ, M_WAITOK); rep->r_nmp = nmp; rep->r_vp = vp; rep->r_td = td; rep->r_procnum = procnum; mrest_len = m_length(mrest, NULL); /* * Get the RPC header with authorization. */ auth_type = RPCAUTH_UNIX; if (cred->cr_ngroups < 1) panic("nfsreq nogrps"); auth_len = ((((cred->cr_ngroups - 1) > nmp->nm_numgrps) ? nmp->nm_numgrps : (cred->cr_ngroups - 1)) << 2) + 5 * NFSX_UNSIGNED; m = nfsm_rpchead(cred, nmp->nm_flag, procnum, auth_type, auth_len, mrest, mrest_len, &mheadend, &xid); /* * For stream protocols, insert a Sun RPC Record Mark. */ if (nmp->nm_sotype == SOCK_STREAM) { M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT); *mtod(m, u_int32_t *) = htonl(0x80000000 | (m->m_pkthdr.len - NFSX_UNSIGNED)); } rep->r_mreq = m; rep->r_xid = xid; tryagain: if (nmp->nm_flag & NFSMNT_SOFT) rep->r_retry = nmp->nm_retry; else rep->r_retry = NFS_MAXREXMIT + 1; /* past clip limit */ rep->r_rtt = rep->r_rexmit = 0; if (proct[procnum] > 0) rep->r_flags = R_TIMING; else rep->r_flags = 0; rep->r_mrep = NULL; /* * Do the client side RPC. */ nfsstats.rpcrequests++; /* * Chain request into list of outstanding requests. Be sure * to put it LAST so timer finds oldest requests first. */ s = splsoftclock(); TAILQ_INSERT_TAIL(&nfs_reqq, rep, r_chain); /* * If backing off another request or avoiding congestion, don't * send this one now but let timer do it. If not timing a request, * do it now. */ if (nmp->nm_so && (nmp->nm_sotype != SOCK_DGRAM || (nmp->nm_flag & NFSMNT_DUMBTIMR) || nmp->nm_sent < nmp->nm_cwnd)) { splx(s); if (nmp->nm_soflags & PR_CONNREQUIRED) error = nfs_sndlock(rep); if (!error) { m2 = m_copym(m, 0, M_COPYALL, M_TRYWAIT); error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep); if (nmp->nm_soflags & PR_CONNREQUIRED) nfs_sndunlock(rep); } if (!error && (rep->r_flags & R_MUSTRESEND) == 0) { nmp->nm_sent += NFS_CWNDSCALE; rep->r_flags |= R_SENT; } } else { splx(s); rep->r_rtt = -1; } /* * Wait for the reply from our send or the timer's. */ if (!error || error == EPIPE) error = nfs_reply(rep); /* * RPC done, unlink the request. */ s = splsoftclock(); TAILQ_REMOVE(&nfs_reqq, rep, r_chain); splx(s); /* * Decrement the outstanding request count. */ if (rep->r_flags & R_SENT) { rep->r_flags &= ~R_SENT; /* paranoia */ nmp->nm_sent -= NFS_CWNDSCALE; } /* * If there was a successful reply and a tprintf msg. * tprintf a response. */ if (!error && (rep->r_flags & R_TPRINTFMSG)) nfs_msg(rep->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname, "is alive again"); mrep = rep->r_mrep; md = rep->r_md; dpos = rep->r_dpos; if (error) { m_freem(rep->r_mreq); free((caddr_t)rep, M_NFSREQ); return (error); } /* * break down the rpc header and check if ok */ tl = nfsm_dissect(u_int32_t *, 3 * NFSX_UNSIGNED); if (*tl++ == rpc_msgdenied) { if (*tl == rpc_mismatch) error = EOPNOTSUPP; else error = EACCES; m_freem(mrep); m_freem(rep->r_mreq); free((caddr_t)rep, M_NFSREQ); return (error); } /* * Just throw away any verifyer (ie: kerberos etc). */ i = fxdr_unsigned(int, *tl++); /* verf type */ i = fxdr_unsigned(int32_t, *tl); /* len */ if (i > 0) nfsm_adv(nfsm_rndup(i)); tl = nfsm_dissect(u_int32_t *, NFSX_UNSIGNED); /* 0 == ok */ if (*tl == 0) { tl = nfsm_dissect(u_int32_t *, NFSX_UNSIGNED); if (*tl != 0) { error = fxdr_unsigned(int, *tl); if ((nmp->nm_flag & NFSMNT_NFSV3) && error == NFSERR_TRYLATER) { m_freem(mrep); error = 0; waituntil = time_second + trylater_delay; while (time_second < waituntil) (void) tsleep(&lbolt, PSOCK, "nqnfstry", 0); trylater_delay *= nfs_backoff[trylater_cnt]; if (trylater_cnt < NFS_NBACKOFF - 1) trylater_cnt++; goto tryagain; } /* * If the File Handle was stale, invalidate the * lookup cache, just in case. */ if (error == ESTALE) cache_purge(vp); if (nmp->nm_flag & NFSMNT_NFSV3) { *mrp = mrep; *mdp = md; *dposp = dpos; error |= NFSERR_RETERR; } else m_freem(mrep); m_freem(rep->r_mreq); free((caddr_t)rep, M_NFSREQ); return (error); } *mrp = mrep; *mdp = md; *dposp = dpos; m_freem(rep->r_mreq); FREE((caddr_t)rep, M_NFSREQ); return (0); } m_freem(mrep); error = EPROTONOSUPPORT; nfsmout: m_freem(rep->r_mreq); free((caddr_t)rep, M_NFSREQ); return (error); } /* * Nfs timer routine * Scan the nfsreq list and retranmit any requests that have timed out * To avoid retransmission attempts on STREAM sockets (in the future) make * sure to set the r_retry field to 0 (implies nm_retry == 0). */ void nfs_timer(void *arg) { struct nfsreq *rep; struct mbuf *m; struct socket *so; struct nfsmount *nmp; int timeo; int s, error; struct thread *td; td = &thread0; /* XXX for credentials, may break if sleep */ s = splnet(); TAILQ_FOREACH(rep, &nfs_reqq, r_chain) { nmp = rep->r_nmp; if (rep->r_mrep || (rep->r_flags & R_SOFTTERM)) continue; if (nfs_sigintr(nmp, rep, rep->r_td)) { nfs_softterm(rep); continue; } if (rep->r_rtt >= 0) { rep->r_rtt++; if (nmp->nm_flag & NFSMNT_DUMBTIMR) timeo = nmp->nm_timeo; else timeo = NFS_RTO(nmp, proct[rep->r_procnum]); if (nmp->nm_timeouts > 0) timeo *= nfs_backoff[nmp->nm_timeouts - 1]; if (rep->r_rtt <= timeo) continue; if (nmp->nm_timeouts < NFS_NBACKOFF) nmp->nm_timeouts++; } /* * Check for server not responding */ if ((rep->r_flags & R_TPRINTFMSG) == 0 && rep->r_rexmit > nmp->nm_deadthresh) { nfs_msg(rep->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname, "not responding"); rep->r_flags |= R_TPRINTFMSG; } if (rep->r_rexmit >= rep->r_retry) { /* too many */ nfsstats.rpctimeouts++; nfs_softterm(rep); continue; } if (nmp->nm_sotype != SOCK_DGRAM) { if (++rep->r_rexmit > NFS_MAXREXMIT) rep->r_rexmit = NFS_MAXREXMIT; continue; } if ((so = nmp->nm_so) == NULL) continue; /* * If there is enough space and the window allows.. * Resend it * Set r_rtt to -1 in case we fail to send it now. */ rep->r_rtt = -1; if (sbspace(&so->so_snd) >= rep->r_mreq->m_pkthdr.len && ((nmp->nm_flag & NFSMNT_DUMBTIMR) || (rep->r_flags & R_SENT) || nmp->nm_sent < nmp->nm_cwnd) && (m = m_copym(rep->r_mreq, 0, M_COPYALL, M_DONTWAIT))){ if ((nmp->nm_flag & NFSMNT_NOCONN) == 0) error = (*so->so_proto->pr_usrreqs->pru_send) (so, 0, m, NULL, NULL, td); else error = (*so->so_proto->pr_usrreqs->pru_send) (so, 0, m, nmp->nm_nam, NULL, td); if (error) { if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) so->so_error = 0; } else { /* * Iff first send, start timing * else turn timing off, backoff timer * and divide congestion window by 2. */ if (rep->r_flags & R_SENT) { rep->r_flags &= ~R_TIMING; if (++rep->r_rexmit > NFS_MAXREXMIT) rep->r_rexmit = NFS_MAXREXMIT; nmp->nm_cwnd >>= 1; if (nmp->nm_cwnd < NFS_CWNDSCALE) nmp->nm_cwnd = NFS_CWNDSCALE; nfsstats.rpcretries++; } else { rep->r_flags |= R_SENT; nmp->nm_sent += NFS_CWNDSCALE; } rep->r_rtt = 0; } } } splx(s); nfs_timer_handle = timeout(nfs_timer, NULL, nfs_ticks); } /* * Mark all of an nfs mount's outstanding requests with R_SOFTTERM and * wait for all requests to complete. This is used by forced unmounts * to terminate any outstanding RPCs. */ int nfs_nmcancelreqs(nmp) struct nfsmount *nmp; { struct nfsreq *req; int i, s; s = splnet(); TAILQ_FOREACH(req, &nfs_reqq, r_chain) { if (nmp != req->r_nmp || req->r_mrep != NULL || (req->r_flags & R_SOFTTERM)) continue; nfs_softterm(req); } splx(s); for (i = 0; i < 30; i++) { s = splnet(); TAILQ_FOREACH(req, &nfs_reqq, r_chain) { if (nmp == req->r_nmp) break; } splx(s); if (req == NULL) return (0); tsleep(&lbolt, PSOCK, "nfscancel", 0); } return (EBUSY); } /* * Flag a request as being about to terminate (due to NFSMNT_INT/NFSMNT_SOFT). * The nm_send count is decremented now to avoid deadlocks when the process in * soreceive() hasn't yet managed to send its own request. */ static void nfs_softterm(struct nfsreq *rep) { rep->r_flags |= R_SOFTTERM; if (rep->r_flags & R_SENT) { rep->r_nmp->nm_sent -= NFS_CWNDSCALE; rep->r_flags &= ~R_SENT; } } /* * Test for a termination condition pending on the process. * This is used for NFSMNT_INT mounts. */ int nfs_sigintr(struct nfsmount *nmp, struct nfsreq *rep, struct thread *td) { struct proc *p; sigset_t tmpset; if (rep && (rep->r_flags & R_SOFTTERM)) return (EINTR); /* Terminate all requests while attempting a forced unmount. */ if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF) return (EINTR); if (!(nmp->nm_flag & NFSMNT_INT)) return (0); if (td == NULL) return (0); p = td->td_proc; PROC_LOCK(p); tmpset = p->p_siglist; SIGSETNAND(tmpset, td->td_sigmask); SIGSETNAND(tmpset, p->p_sigignore); if (SIGNOTEMPTY(p->p_siglist) && NFSINT_SIGMASK(tmpset)) { PROC_UNLOCK(p); return (EINTR); } PROC_UNLOCK(p); return (0); } /* * Lock a socket against others. * Necessary for STREAM sockets to ensure you get an entire rpc request/reply * and also to avoid race conditions between the processes with nfs requests * in progress when a reconnect is necessary. */ int nfs_sndlock(struct nfsreq *rep) { int *statep = &rep->r_nmp->nm_state; struct thread *td; int slpflag = 0, slptimeo = 0; td = rep->r_td; if (rep->r_nmp->nm_flag & NFSMNT_INT) slpflag = PCATCH; while (*statep & NFSSTA_SNDLOCK) { if (nfs_sigintr(rep->r_nmp, rep, td)) return (EINTR); *statep |= NFSSTA_WANTSND; (void) tsleep(statep, slpflag | (PZERO - 1), "nfsndlck", slptimeo); if (slpflag == PCATCH) { slpflag = 0; slptimeo = 2 * hz; } } *statep |= NFSSTA_SNDLOCK; return (0); } /* * Unlock the stream socket for others. */ void nfs_sndunlock(struct nfsreq *rep) { int *statep = &rep->r_nmp->nm_state; if ((*statep & NFSSTA_SNDLOCK) == 0) panic("nfs sndunlock"); *statep &= ~NFSSTA_SNDLOCK; if (*statep & NFSSTA_WANTSND) { *statep &= ~NFSSTA_WANTSND; wakeup(statep); } } static int nfs_rcvlock(struct nfsreq *rep) { int *statep = &rep->r_nmp->nm_state; int slpflag, slptimeo = 0; if (rep->r_nmp->nm_flag & NFSMNT_INT) slpflag = PCATCH; else slpflag = 0; while (*statep & NFSSTA_RCVLOCK) { if (nfs_sigintr(rep->r_nmp, rep, rep->r_td)) return (EINTR); *statep |= NFSSTA_WANTRCV; (void) tsleep(statep, slpflag | (PZERO - 1), "nfsrcvlk", slptimeo); /* * If our reply was recieved while we were sleeping, * then just return without taking the lock to avoid a * situation where a single iod could 'capture' the * recieve lock. */ if (rep->r_mrep != NULL) return (EALREADY); if (slpflag == PCATCH) { slpflag = 0; slptimeo = 2 * hz; } } /* Always fail if our request has been cancelled. */ if (rep != NULL && (rep->r_flags & R_SOFTTERM)) return (EINTR); *statep |= NFSSTA_RCVLOCK; return (0); } /* * Unlock the stream socket for others. */ static void nfs_rcvunlock(struct nfsreq *rep) { int *statep = &rep->r_nmp->nm_state; if ((*statep & NFSSTA_RCVLOCK) == 0) panic("nfs rcvunlock"); *statep &= ~NFSSTA_RCVLOCK; if (*statep & NFSSTA_WANTRCV) { *statep &= ~NFSSTA_WANTRCV; wakeup(statep); } } /* * nfs_realign: * * Check for badly aligned mbuf data and realign by copying the unaligned * portion of the data into a new mbuf chain and freeing the portions * of the old chain that were replaced. * * We cannot simply realign the data within the existing mbuf chain * because the underlying buffers may contain other rpc commands and * we cannot afford to overwrite them. * * We would prefer to avoid this situation entirely. The situation does * not occur with NFS/UDP and is supposed to only occassionally occur * with TCP. Use vfs.nfs.realign_count and realign_test to check this. */ static void nfs_realign(struct mbuf **pm, int hsiz) { struct mbuf *m; struct mbuf *n = NULL; int off = 0; ++nfs_realign_test; while ((m = *pm) != NULL) { if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3)) { MGET(n, M_TRYWAIT, MT_DATA); if (m->m_len >= MINCLSIZE) { MCLGET(n, M_TRYWAIT); } n->m_len = 0; break; } pm = &m->m_next; } /* * If n is non-NULL, loop on m copying data, then replace the * portion of the chain that had to be realigned. */ if (n != NULL) { ++nfs_realign_count; while (m) { m_copyback(n, off, m->m_len, mtod(m, caddr_t)); off += m->m_len; m = m->m_next; } m_freem(*pm); *pm = n; } } static int nfs_msg(struct thread *td, char *server, char *msg) { tprintf(td ? td->td_proc : NULL, LOG_INFO, "nfs server %s: %s\n", server, msg); return (0); }