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freebsd-skq/sys/nfsclient/nfs_socket.c
Chuck Lever 94163ea283 Refactor the NFS over UDP retransmit timeout estimation logic to allow 
the estimator to be more easily tuned and maintained.

There should be no functional change except there is now a lower limit
on the retransmit timeout to prevent the client from retransmitting
faster than the server's disks can fill requests, and an upper limit
to prevent the estimator from taking to long to retransmit during a
server outage.

Reviewed by:	mohan, kris, silby
Sponsored by:	Network Appliance, Incorporated
2006-05-23 18:33:58 +00:00

1912 lines
49 KiB
C
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/*-
* 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.
* 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Socket operations for use by nfs
*/
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/signalvar.h>
#include <sys/syscallsubr.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/vnode.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <rpc/rpcclnt.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfsclient/nfs.h>
#include <nfs/xdr_subs.h>
#include <nfsclient/nfsm_subs.h>
#include <nfsclient/nfsmount.h>
#include <nfsclient/nfsnode.h>
#include <nfs4client/nfs4.h>
#define TRUE 1
#define FALSE 0
extern u_int32_t nfs_xid;
static int nfs_realign_test;
static int nfs_realign_count;
static int nfs_bufpackets = 4;
static int nfs_reconnects;
static int nfs3_jukebox_delay = 10;
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, "");
SYSCTL_INT(_vfs_nfs, OID_AUTO, reconnects, CTLFLAG_RD, &nfs_reconnects, 0,
"number of times the nfs client has had to reconnect");
SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs3_jukebox_delay, CTLFLAG_RW, &nfs3_jukebox_delay, 0,
"number of seconds to delay a retry after receiving EJUKEBOX");
/*
* 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 nfs_callout;
static int nfs_msg(struct thread *, const char *, const char *, int);
static int nfs_realign(struct mbuf **pm, int hsiz);
static int nfs_reply(struct nfsreq *);
static void nfs_softterm(struct nfsreq *rep);
static int nfs_reconnect(struct nfsreq *rep);
static void nfs_clnt_tcp_soupcall(struct socket *so, void *arg, int waitflag);
static void nfs_clnt_udp_soupcall(struct socket *so, void *arg, int waitflag);
extern struct mtx nfs_reqq_mtx;
/*
* RTT estimator
*/
static enum nfs_rto_timer_t nfs_proct[NFS_NPROCS] = {
NFS_DEFAULT_TIMER, /* NULL */
NFS_GETATTR_TIMER, /* GETATTR */
NFS_DEFAULT_TIMER, /* SETATTR */
NFS_LOOKUP_TIMER, /* LOOKUP */
NFS_GETATTR_TIMER, /* ACCESS */
NFS_READ_TIMER, /* READLINK */
NFS_READ_TIMER, /* READ */
NFS_WRITE_TIMER, /* WRITE */
NFS_DEFAULT_TIMER, /* CREATE */
NFS_DEFAULT_TIMER, /* MKDIR */
NFS_DEFAULT_TIMER, /* SYMLINK */
NFS_DEFAULT_TIMER, /* MKNOD */
NFS_DEFAULT_TIMER, /* REMOVE */
NFS_DEFAULT_TIMER, /* RMDIR */
NFS_DEFAULT_TIMER, /* RENAME */
NFS_DEFAULT_TIMER, /* LINK */
NFS_READ_TIMER, /* READDIR */
NFS_READ_TIMER, /* READDIRPLUS */
NFS_DEFAULT_TIMER, /* FSSTAT */
NFS_DEFAULT_TIMER, /* FSINFO */
NFS_DEFAULT_TIMER, /* PATHCONF */
NFS_DEFAULT_TIMER, /* COMMIT */
NFS_DEFAULT_TIMER, /* NOOP */
};
/*
* Choose the correct RTT timer for this NFS procedure.
*/
static inline enum nfs_rto_timer_t
nfs_rto_timer(u_int32_t procnum)
{
return nfs_proct[procnum];
}
/*
* Initialize the RTT estimator state for a new mount point.
*/
static void
nfs_init_rtt(struct nfsmount *nmp)
{
int i;
for (i = 0; i < NFS_MAX_TIMER; i++)
nmp->nm_srtt[i] = NFS_INITRTT;
for (i = 0; i < NFS_MAX_TIMER; i++)
nmp->nm_sdrtt[i] = 0;
}
/*
* Update a mount point's RTT estimator state using data from the
* passed-in request.
*
* Use a gain of 0.125 on the mean and a gain of 0.25 on the deviation.
*
* NB: 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 before calculating the
* update values.
*/
static void
nfs_update_rtt(struct nfsreq *rep)
{
int t1 = rep->r_rtt + 1;
int index = nfs_rto_timer(rep->r_procnum) - 1;
int *srtt = &rep->r_nmp->nm_srtt[index];
int *sdrtt = &rep->r_nmp->nm_sdrtt[index];
t1 -= *srtt >> 3;
*srtt += t1;
if (t1 < 0)
t1 = -t1;
t1 -= *sdrtt >> 2;
*sdrtt += t1;
}
/*
* 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
*/
static int
nfs_estimate_rto(struct nfsmount *nmp, u_int32_t procnum)
{
enum nfs_rto_timer_t timer = nfs_rto_timer(procnum);
int index = timer - 1;
int rto;
switch (timer) {
case NFS_GETATTR_TIMER:
case NFS_LOOKUP_TIMER:
rto = ((nmp->nm_srtt[index] + 3) >> 2) +
((nmp->nm_sdrtt[index] + 1) >> 1);
break;
case NFS_READ_TIMER:
case NFS_WRITE_TIMER:
rto = ((nmp->nm_srtt[index] + 7) >> 3) +
(nmp->nm_sdrtt[index] + 1);
break;
default:
rto = nmp->nm_timeo;
return (rto);
}
if (rto < NFS_MINRTO)
rto = NFS_MINRTO;
else if (rto > NFS_MAXRTO)
rto = NFS_MAXRTO;
return (rto);
}
/*
* 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 error, rcvreserve, sndreserve;
int pktscale;
struct sockaddr *saddr;
struct thread *td = &thread0; /* only used for socreate and sobind */
NET_LOCK_GIANT();
if (nmp->nm_sotype == SOCK_STREAM) {
mtx_lock(&nmp->nm_mtx);
nmp->nm_nfstcpstate.flags |= NFS_TCP_EXPECT_RPCMARKER;
nmp->nm_nfstcpstate.rpcresid = 0;
mtx_unlock(&nmp->nm_mtx);
}
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.
*/
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_flag & NFSMNT_NOCONN) {
if (nmp->nm_soflags & PR_CONNREQUIRED) {
error = ENOTCONN;
mtx_unlock(&nmp->nm_mtx);
goto bad;
} else
mtx_unlock(&nmp->nm_mtx);
} else {
mtx_unlock(&nmp->nm_mtx);
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.
*/
SOCK_LOCK(so);
while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
(void) msleep(&so->so_timeo, SOCK_MTX(so),
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;
SOCK_UNLOCK(so);
goto bad;
}
}
if (so->so_error) {
error = so->so_error;
so->so_error = 0;
SOCK_UNLOCK(so);
goto bad;
}
SOCK_UNLOCK(so);
}
so->so_rcv.sb_timeo = 12 * 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;
mtx_lock(&nmp->nm_mtx);
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_dir = SOPT_SET;
sopt.sopt_level = SOL_SOCKET;
sopt.sopt_name = SO_KEEPALIVE;
sopt.sopt_val = &val;
sopt.sopt_valsize = sizeof val;
val = 1;
mtx_unlock(&nmp->nm_mtx);
sosetopt(so, &sopt);
mtx_lock(&nmp->nm_mtx);
}
if (so->so_proto->pr_protocol == IPPROTO_TCP) {
struct sockopt sopt;
int val;
bzero(&sopt, sizeof sopt);
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = IPPROTO_TCP;
sopt.sopt_name = TCP_NODELAY;
sopt.sopt_val = &val;
sopt.sopt_valsize = sizeof val;
val = 1;
mtx_unlock(&nmp->nm_mtx);
sosetopt(so, &sopt);
mtx_lock(&nmp->nm_mtx);
}
sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR +
sizeof (u_int32_t)) * pktscale;
rcvreserve = (nmp->nm_rsize + NFS_MAXPKTHDR +
sizeof (u_int32_t)) * pktscale;
}
mtx_unlock(&nmp->nm_mtx);
error = soreserve(so, sndreserve, rcvreserve);
if (error)
goto bad;
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_flags |= SB_NOINTR;
so->so_upcallarg = (caddr_t)nmp;
if (so->so_type == SOCK_STREAM)
so->so_upcall = nfs_clnt_tcp_soupcall;
else
so->so_upcall = nfs_clnt_udp_soupcall;
so->so_rcv.sb_flags |= SB_UPCALL;
SOCKBUF_UNLOCK(&so->so_rcv);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_flags |= SB_NOINTR;
SOCKBUF_UNLOCK(&so->so_snd);
mtx_lock(&nmp->nm_mtx);
/* Initialize other non-zero congestion variables */
nfs_init_rtt(nmp);
nmp->nm_cwnd = NFS_MAXCWND / 2; /* Initial send window */
nmp->nm_sent = 0;
nmp->nm_timeouts = 0;
mtx_unlock(&nmp->nm_mtx);
NET_UNLOCK_GIANT();
return (0);
bad:
nfs_disconnect(nmp);
NET_UNLOCK_GIANT();
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_reconnects++;
nfs_disconnect(nmp);
while ((error = nfs_connect(nmp, rep)) != 0) {
if (error == ERESTART)
error = EINTR;
if (error == EIO || error == EINTR)
return (error);
mtx_lock(&Giant);
(void) tsleep(&lbolt, PSOCK, "nfscon", 0);
mtx_unlock(&Giant);
}
/*
* Clear the FORCE_RECONNECT flag only after the connect
* succeeds. To prevent races between multiple processes
* waiting on the mountpoint where the connection is being
* torn down. The first one to acquire the sndlock will
* retry the connection. The others block on the sndlock
* until the connection is established successfully, and
* then re-transmit the request.
*/
mtx_lock(&nmp->nm_mtx);
nmp->nm_nfstcpstate.flags &= ~NFS_TCP_FORCE_RECONNECT;
nmp->nm_nfstcpstate.rpcresid = 0;
mtx_unlock(&nmp->nm_mtx);
/*
* Loop through outstanding request list and fix up all requests
* on old socket.
*/
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(rp, &nfs_reqq, r_chain) {
if (rp->r_nmp == nmp) {
mtx_lock(&rp->r_mtx);
rp->r_flags |= R_MUSTRESEND;
mtx_unlock(&rp->r_mtx);
}
}
mtx_unlock(&nfs_reqq_mtx);
return (0);
}
/*
* NFS disconnect. Clean up and unlink.
*/
void
nfs_disconnect(struct nfsmount *nmp)
{
struct socket *so;
NET_ASSERT_GIANT();
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_so) {
so = nmp->nm_so;
nmp->nm_so = NULL;
mtx_unlock(&nmp->nm_mtx);
SOCKBUF_LOCK(&so->so_rcv);
so->so_upcallarg = NULL;
so->so_upcall = NULL;
so->so_rcv.sb_flags &= ~SB_UPCALL;
SOCKBUF_UNLOCK(&so->so_rcv);
soshutdown(so, SHUT_WR);
soclose(so);
} else
mtx_unlock(&nmp->nm_mtx);
}
void
nfs_safedisconnect(struct nfsmount *nmp)
{
struct nfsreq dummyreq;
bzero(&dummyreq, sizeof(dummyreq));
dummyreq.r_nmp = nmp;
nfs_disconnect(nmp);
}
/*
* 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, error2, soflags, flags;
NET_LOCK_GIANT();
KASSERT(rep, ("nfs_send: called with rep == NULL"));
error = nfs_sigintr(rep->r_nmp, rep, rep->r_td);
if (error) {
m_freem(top);
goto out;
}
mtx_lock(&rep->r_nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
if ((so = rep->r_nmp->nm_so) == NULL) {
rep->r_flags |= R_MUSTRESEND;
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
m_freem(top);
error = 0;
goto out;
}
rep->r_flags &= ~R_MUSTRESEND;
soflags = rep->r_nmp->nm_soflags;
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
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;
mtx_lock(&rep->r_mtx);
rep->r_flags |= R_MUSTRESEND;
mtx_unlock(&rep->r_mtx);
}
if (error) {
/*
* Don't report EPIPE errors on nfs sockets.
* These can be due to idle tcp mounts which will be closed by
* netapp, solaris, etc. if left idle too long.
*/
if (error != EPIPE) {
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.
*/
error2 = NFS_SIGREP(rep);
if (error2)
error = error2;
else {
mtx_lock(&rep->r_mtx);
rep->r_flags |= R_MUSTRESEND;
mtx_unlock(&rep->r_mtx);
}
/*
* Handle any recoverable (soft) socket errors here. (?)
*/
if (error != EINTR && error != ERESTART && error != EIO &&
error != EWOULDBLOCK && error != EPIPE)
error = 0;
}
out:
NET_UNLOCK_GIANT();
return (error);
}
int
nfs_reply(struct nfsreq *rep)
{
register struct socket *so;
register struct mbuf *m;
int error = 0, sotype, slpflag;
NET_LOCK_GIANT();
sotype = rep->r_nmp->nm_sotype;
/*
* For reliable protocols, lock against other senders/receivers
* in case a reconnect is necessary.
*/
if (sotype != SOCK_DGRAM) {
error = nfs_sndlock(rep);
if (error)
goto out;
tryagain:
mtx_lock(&rep->r_nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
if (rep->r_mrep) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
nfs_sndunlock(rep);
error = 0;
goto out;
}
if (rep->r_flags & R_SOFTTERM) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
nfs_sndunlock(rep);
error = EINTR;
goto out;
}
so = rep->r_nmp->nm_so;
if (!so ||
(rep->r_nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT)) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
error = nfs_reconnect(rep);
if (error) {
nfs_sndunlock(rep);
goto out;
}
goto tryagain;
}
while (rep->r_flags & R_MUSTRESEND) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAIT);
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);
goto out;
}
goto tryagain;
}
mtx_lock(&rep->r_nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
}
mtx_unlock(&rep->r_nmp->nm_mtx);
mtx_unlock(&rep->r_mtx);
nfs_sndunlock(rep);
}
slpflag = 0;
mtx_lock(&rep->r_nmp->nm_mtx);
if (rep->r_nmp->nm_flag & NFSMNT_INT)
slpflag = PCATCH;
mtx_unlock(&rep->r_nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
while ((rep->r_mrep == NULL) && (error == 0) &&
((rep->r_flags & R_SOFTTERM) == 0) &&
((sotype == SOCK_DGRAM) || ((rep->r_flags & R_MUSTRESEND) == 0)))
error = msleep((caddr_t)rep, &rep->r_mtx,
slpflag | (PZERO - 1), "nfsreq", 0);
if (error == EINTR || error == ERESTART) {
/* NFS operations aren't restartable. Map ERESTART to EINTR */
error = EINTR;
mtx_unlock(&rep->r_mtx);
goto out;
}
if (rep->r_flags & R_SOFTTERM) {
/* Request was terminated because we exceeded the retries (soft mount) */
error = ETIMEDOUT;
mtx_unlock(&rep->r_mtx);
goto out;
}
mtx_unlock(&rep->r_mtx);
if (sotype == SOCK_STREAM) {
mtx_lock(&rep->r_nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
if (((rep->r_nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT) ||
(rep->r_flags & R_MUSTRESEND))) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
error = nfs_sndlock(rep);
if (error)
goto out;
goto tryagain;
} else {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&rep->r_nmp->nm_mtx);
}
}
out:
NET_UNLOCK_GIANT();
return (error);
}
/*
* XXX TO DO
* Make nfs_realign() non-blocking. Also make nfsm_dissect() nonblocking.
*/
static void
nfs_clnt_match_xid(struct socket *so,
struct nfsmount *nmp,
struct mbuf *mrep)
{
struct mbuf *md;
caddr_t dpos;
u_int32_t rxid, *tl;
struct nfsreq *rep;
int error;
/*
* 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.
*/
if (nfs_realign(&mrep, 5 * NFSX_UNSIGNED) == ENOMEM) {
m_freem(mrep);
nfsstats.rpcinvalid++;
return;
}
/*
* Get the xid and check that it is an rpc reply
*/
md = mrep;
dpos = mtod(md, caddr_t);
tl = nfsm_dissect_nonblock(u_int32_t *, 2*NFSX_UNSIGNED);
rxid = *tl++;
if (*tl != rpc_reply) {
m_freem(mrep);
nfsmout:
nfsstats.rpcinvalid++;
return;
}
mtx_lock(&nfs_reqq_mtx);
/*
* Loop through the request list to match up the reply
* Iff no match, just drop the datagram
*/
TAILQ_FOREACH(rep, &nfs_reqq, r_chain) {
mtx_lock(&nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
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;
}
if (rep->r_flags & R_TIMING)
nfs_update_rtt(rep);
nmp->nm_timeouts = 0;
wakeup((caddr_t)rep);
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
break;
}
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
}
/*
* If not matched to a request, drop it.
* If it's mine, wake up requestor.
*/
if (rep == 0) {
nfsstats.rpcunexpected++;
m_freem(mrep);
}
mtx_unlock(&nfs_reqq_mtx);
}
static void
nfs_mark_for_reconnect(struct nfsmount *nmp)
{
struct nfsreq *rp;
mtx_lock(&nmp->nm_mtx);
nmp->nm_nfstcpstate.flags |= NFS_TCP_FORCE_RECONNECT;
mtx_unlock(&nmp->nm_mtx);
/*
* Wakeup all processes that are waiting for replies
* on this mount point. One of them does the reconnect.
*/
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(rp, &nfs_reqq, r_chain) {
if (rp->r_nmp == nmp) {
mtx_lock(&rp->r_mtx);
rp->r_flags |= R_MUSTRESEND;
wakeup((caddr_t)rp);
mtx_unlock(&rp->r_mtx);
}
}
mtx_unlock(&nfs_reqq_mtx);
}
static int
nfstcp_readable(struct socket *so, int bytes)
{
int retval;
SOCKBUF_LOCK(&so->so_rcv);
retval = (so->so_rcv.sb_cc >= (bytes) ||
(so->so_rcv.sb_state & SBS_CANTRCVMORE) ||
so->so_error);
SOCKBUF_UNLOCK(&so->so_rcv);
return (retval);
}
#define nfstcp_marker_readable(so) nfstcp_readable(so, sizeof(u_int32_t))
static int
nfs_copy_len(struct mbuf *mp, char *buf, int len)
{
while (len > 0 && mp != NULL) {
int copylen = min(len, mp->m_len);
bcopy(mp->m_data, buf, copylen);
buf += copylen;
len -= copylen;
mp = mp->m_next;
}
return (len);
}
static void
nfs_clnt_tcp_soupcall(struct socket *so, void *arg, int waitflag)
{
struct nfsmount *nmp = (struct nfsmount *)arg;
struct mbuf *mp = NULL;
struct uio auio;
int error;
u_int32_t len;
int rcvflg;
/*
* Don't pick any more data from the socket if we've marked the
* mountpoint for reconnect.
*/
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT) {
mtx_unlock(&nmp->nm_mtx);
return;
} else
mtx_unlock(&nmp->nm_mtx);
auio.uio_td = curthread;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_READ;
for ( ; ; ) {
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_nfstcpstate.flags & NFS_TCP_EXPECT_RPCMARKER) {
int resid;
mtx_unlock(&nmp->nm_mtx);
if (!nfstcp_marker_readable(so)) {
/* Marker is not readable */
return;
}
auio.uio_resid = sizeof(u_int32_t);
auio.uio_iov = NULL;
auio.uio_iovcnt = 0;
mp = NULL;
rcvflg = (MSG_DONTWAIT | MSG_SOCALLBCK);
error = so->so_proto->pr_usrreqs->pru_soreceive
(so, (struct sockaddr **)0,
&auio, &mp, (struct mbuf **)0, &rcvflg);
/*
* We've already tested that the socket is readable. 2 cases
* here, we either read 0 bytes (client closed connection),
* or got some other error. In both cases, we tear down the
* connection.
*/
if (error || auio.uio_resid > 0) {
if (error && error != ECONNRESET) {
log(LOG_ERR,
"nfs/tcp clnt: Error %d reading socket, tearing down TCP connection\n",
error);
}
goto mark_reconnect;
}
if (mp == NULL)
panic("nfs_clnt_tcp_soupcall: Got empty mbuf chain from sorecv\n");
/*
* Sigh. We can't do the obvious thing here (which would
* be to have soreceive copy the length from mbufs for us).
* Calling uiomove() from the context of a socket callback
* (even for kernel-kernel copies) leads to LORs (since
* we hold network locks at this point).
*/
if ((resid = nfs_copy_len(mp, (char *)&len,
sizeof(u_int32_t)))) {
log(LOG_ERR, "%s (%d) from nfs server %s\n",
"Bad RPC HDR length",
(int)(sizeof(u_int32_t) - resid),
nmp->nm_mountp->mnt_stat.f_mntfromname);
goto mark_reconnect;
}
len = ntohl(len) & ~0x80000000;
m_freem(mp);
/*
* 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 || len == 0) {
log(LOG_ERR, "%s (%d) from nfs server %s\n",
"impossible packet length",
len,
nmp->nm_mountp->mnt_stat.f_mntfromname);
goto mark_reconnect;
}
mtx_lock(&nmp->nm_mtx);
nmp->nm_nfstcpstate.rpcresid = len;
nmp->nm_nfstcpstate.flags &= ~(NFS_TCP_EXPECT_RPCMARKER);
mtx_unlock(&nmp->nm_mtx);
} else
mtx_unlock(&nmp->nm_mtx);
/*
* Processed RPC marker or no RPC marker to process.
* Pull in and process data.
*/
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_nfstcpstate.rpcresid > 0) {
mtx_unlock(&nmp->nm_mtx);
if (!nfstcp_readable(so, nmp->nm_nfstcpstate.rpcresid)) {
/* All data not readable */
return;
}
auio.uio_resid = nmp->nm_nfstcpstate.rpcresid;
auio.uio_iov = NULL;
auio.uio_iovcnt = 0;
mp = NULL;
rcvflg = (MSG_DONTWAIT | MSG_SOCALLBCK);
error = so->so_proto->pr_usrreqs->pru_soreceive
(so, (struct sockaddr **)0,
&auio, &mp, (struct mbuf **)0, &rcvflg);
if (error || auio.uio_resid > 0) {
if (error && error != ECONNRESET) {
log(LOG_ERR,
"nfs/tcp clnt: Error %d reading socket, tearing down TCP connection\n",
error);
}
goto mark_reconnect;
}
if (mp == NULL)
panic("nfs_clnt_tcp_soupcall: Got empty mbuf chain from sorecv\n");
mtx_lock(&nmp->nm_mtx);
nmp->nm_nfstcpstate.rpcresid = 0;
nmp->nm_nfstcpstate.flags |= NFS_TCP_EXPECT_RPCMARKER;
mtx_unlock(&nmp->nm_mtx);
/* We got the entire RPC reply. Match XIDs and wake up requestor */
nfs_clnt_match_xid(so, nmp, mp);
} else
mtx_unlock(&nmp->nm_mtx);
}
mark_reconnect:
nfs_mark_for_reconnect(nmp);
}
static void
nfs_clnt_udp_soupcall(struct socket *so, void *arg, int waitflag)
{
struct nfsmount *nmp = (struct nfsmount *)arg;
struct uio auio;
struct mbuf *mp = NULL;
struct mbuf *control = NULL;
int error, rcvflag;
auio.uio_resid = 1000000;
auio.uio_td = curthread;
rcvflag = MSG_DONTWAIT;
auio.uio_resid = 1000000000;
do {
mp = control = NULL;
error = so->so_proto->pr_usrreqs->pru_soreceive(so,
NULL, &auio, &mp,
&control, &rcvflag);
if (control)
m_freem(control);
if (mp)
nfs_clnt_match_xid(so, nmp, mp);
} while (mp && !error);
}
/*
* 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
*/
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 error = 0, mrest_len, auth_len, auth_type;
struct timeval now;
u_int32_t *xidp;
/* 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);
if ((nmp->nm_flag & NFSMNT_NFSV4) != 0)
return nfs4_request(vp, mrest, procnum, td, cred, mrp, mdp, dposp);
MALLOC(rep, struct nfsreq *, sizeof(struct nfsreq), M_NFSREQ, M_WAITOK);
bzero(rep, sizeof(struct nfsreq));
rep->r_nmp = nmp;
rep->r_vp = vp;
rep->r_td = td;
rep->r_procnum = procnum;
mtx_init(&rep->r_mtx, "NFSrep lock", NULL, MTX_DEF);
getmicrouptime(&now);
rep->r_lastmsg = now.tv_sec -
((nmp->nm_tprintf_delay) - (nmp->nm_tprintf_initial_delay));
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, &xidp);
/*
* 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 = *xidp;
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 (nfs_rto_timer(procnum) != NFS_DEFAULT_TIMER)
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.
*/
mtx_lock(&nfs_reqq_mtx);
if (TAILQ_EMPTY(&nfs_reqq))
callout_reset(&nfs_callout, nfs_ticks, nfs_timer, NULL);
TAILQ_INSERT_TAIL(&nfs_reqq, rep, r_chain);
mtx_unlock(&nfs_reqq_mtx);
/*
* 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.
*/
mtx_lock(&nmp->nm_mtx);
if (nmp->nm_so && (nmp->nm_sotype != SOCK_DGRAM ||
(nmp->nm_flag & NFSMNT_DUMBTIMR) ||
nmp->nm_sent < nmp->nm_cwnd)) {
mtx_unlock(&nmp->nm_mtx);
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);
nfs_sndunlock(rep);
}
mtx_lock(&nfs_reqq_mtx);
/*
* nfs_timer() could've re-transmitted the request if we ended up
* blocking on nfs_send() too long, so check for R_SENT here.
*/
if (!error && (rep->r_flags & (R_SENT | R_MUSTRESEND)) == 0) {
mtx_lock(&nmp->nm_mtx);
nmp->nm_sent += NFS_CWNDSCALE;
mtx_unlock(&nmp->nm_mtx);
rep->r_flags |= R_SENT;
}
mtx_unlock(&nfs_reqq_mtx);
} else {
mtx_unlock(&nmp->nm_mtx);
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.
*/
mtx_lock(&nfs_reqq_mtx);
/*
* nfs_timer() may be in the process of re-transmitting this request.
* nfs_timer() drops the nfs_reqq_mtx before the pru_send() (to avoid LORs).
* Wait till nfs_timer() completes the re-transmission. When the reply
* comes back, it will be discarded (since the req struct for it no longer
* exists).
*/
while (rep->r_flags & R_REXMIT_INPROG) {
msleep((caddr_t)&rep->r_flags, &nfs_reqq_mtx,
(PZERO - 1), "nfsrxmt", 0);
}
TAILQ_REMOVE(&nfs_reqq, rep, r_chain);
if (TAILQ_EMPTY(&nfs_reqq))
callout_stop(&nfs_callout);
/*
* Decrement the outstanding request count.
*/
if (rep->r_flags & R_SENT) {
rep->r_flags &= ~R_SENT; /* paranoia */
mtx_lock(&nmp->nm_mtx);
nmp->nm_sent -= NFS_CWNDSCALE;
mtx_unlock(&nmp->nm_mtx);
}
mtx_unlock(&nfs_reqq_mtx);
/*
* If there was a successful reply and a tprintf msg.
* tprintf a response.
*/
if (!error) {
mtx_lock(&Giant);
nfs_up(rep, nmp, rep->r_td, "is alive again", NFSSTA_TIMEO);
mtx_unlock(&Giant);
}
mrep = rep->r_mrep;
md = rep->r_md;
dpos = rep->r_dpos;
if (error) {
/*
* If we got interrupted by a signal in nfs_reply(), there's
* a very small window where the reply could've come in before
* this process got scheduled in. To handle that case, we need
* to free the reply if it was delivered.
*/
if (rep->r_mrep != NULL)
m_freem(rep->r_mrep);
m_freem(rep->r_mreq);
mtx_destroy(&rep->r_mtx);
free((caddr_t)rep, M_NFSREQ);
return (error);
}
if (rep->r_mrep == NULL)
panic("nfs_request: rep->r_mrep shouldn't be NULL if no error\n");
/*
* 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);
mtx_destroy(&rep->r_mtx);
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 + nfs3_jukebox_delay;
while (time_second < waituntil) {
mtx_lock(&Giant);
(void) tsleep(&lbolt, PSOCK, "nqnfstry", 0);
mtx_unlock(&Giant);
}
mtx_lock(&nfs_reqq_mtx);
if (++nfs_xid == 0)
nfs_xid++;
rep->r_xid = *xidp = txdr_unsigned(nfs_xid);
mtx_unlock(&nfs_reqq_mtx);
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);
mtx_destroy(&rep->r_mtx);
free((caddr_t)rep, M_NFSREQ);
return (error);
}
*mrp = mrep;
*mdp = md;
*dposp = dpos;
m_freem(rep->r_mreq);
mtx_destroy(&rep->r_mtx);
FREE((caddr_t)rep, M_NFSREQ);
return (0);
}
m_freem(mrep);
error = EPROTONOSUPPORT;
nfsmout:
m_freem(rep->r_mreq);
mtx_destroy(&rep->r_mtx);
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).
*
* The nfs reqq lock cannot be held while we do the pru_send() because of a
* lock ordering violation. The NFS client socket callback acquires
* inp_lock->nfsreq mutex and pru_send acquires inp_lock. So we drop the
* reqq mutex (and reacquire it after the pru_send()). The req structure
* (for the rexmit) is prevented from being removed by the R_REXMIT_INPROG flag.
*/
void
nfs_timer(void *arg)
{
struct nfsreq *rep;
struct mbuf *m;
struct socket *so;
struct nfsmount *nmp;
int timeo;
int error;
struct timeval now;
getmicrouptime(&now);
mtx_lock(&Giant); /* nfs_down -> tprintf */
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(rep, &nfs_reqq, r_chain) {
nmp = rep->r_nmp;
mtx_lock(&rep->r_mtx);
if (rep->r_mrep || (rep->r_flags & R_SOFTTERM)) {
mtx_unlock(&rep->r_mtx);
continue;
} else
mtx_unlock(&rep->r_mtx);
if (nfs_sigintr(nmp, rep, rep->r_td))
continue;
mtx_lock(&nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
if (nmp->nm_tprintf_initial_delay != 0 &&
(rep->r_rexmit > 2 || (rep->r_flags & R_RESENDERR)) &&
rep->r_lastmsg + nmp->nm_tprintf_delay < now.tv_sec) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
rep->r_lastmsg = now.tv_sec;
nfs_down(rep, nmp, rep->r_td, "not responding",
0, NFSSTA_TIMEO);
mtx_lock(&nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
}
if (rep->r_rtt >= 0) {
rep->r_rtt++;
if (nmp->nm_flag & NFSMNT_DUMBTIMR)
timeo = nmp->nm_timeo;
else
timeo = nfs_estimate_rto(nmp, rep->r_procnum);
if (nmp->nm_timeouts > 0)
timeo *= nfs_backoff[nmp->nm_timeouts - 1];
if (rep->r_rtt <= timeo) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
continue;
}
if (nmp->nm_timeouts < NFS_NBACKOFF)
nmp->nm_timeouts++;
}
if (rep->r_rexmit >= rep->r_retry) { /* too many */
nfsstats.rpctimeouts++;
nfs_softterm(rep);
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
continue;
}
if (nmp->nm_sotype != SOCK_DGRAM) {
if (++rep->r_rexmit > NFS_MAXREXMIT)
rep->r_rexmit = NFS_MAXREXMIT;
/*
* For NFS/TCP, setting R_MUSTRESEND and waking up
* the requester will cause the request to be
* retransmitted (in nfs_reply()), re-connecting
* if necessary.
*/
rep->r_flags |= R_MUSTRESEND;
wakeup((caddr_t)rep);
rep->r_rtt = 0;
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
continue;
}
if ((so = nmp->nm_so) == NULL) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
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)) {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
if ((m = m_copym(rep->r_mreq, 0, M_COPYALL, M_DONTWAIT))) {
/*
* Mark the request to indicate that a XMIT is in
* progress to prevent the req structure being
* removed in nfs_request().
*/
mtx_lock(&rep->r_mtx);
rep->r_flags |= R_REXMIT_INPROG;
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nfs_reqq_mtx);
NET_LOCK_GIANT();
if ((nmp->nm_flag & NFSMNT_NOCONN) == 0)
error = (*so->so_proto->pr_usrreqs->pru_send)
(so, 0, m, NULL, NULL, curthread);
else
error = (*so->so_proto->pr_usrreqs->pru_send)
(so, 0, m, nmp->nm_nam, NULL,
curthread);
NET_UNLOCK_GIANT();
mtx_lock(&nfs_reqq_mtx);
mtx_lock(&nmp->nm_mtx);
mtx_lock(&rep->r_mtx);
rep->r_flags &= ~R_REXMIT_INPROG;
wakeup((caddr_t)&rep->r_flags);
if (error) {
if (NFSIGNORE_SOERROR(nmp->nm_soflags, error))
so->so_error = 0;
rep->r_flags |= R_RESENDERR;
} else {
/*
* Iff first send, start timing
* else turn timing off, backoff timer
* and divide congestion window by 2.
*/
rep->r_flags &= ~R_RESENDERR;
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;
}
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
}
} else {
mtx_unlock(&rep->r_mtx);
mtx_unlock(&nmp->nm_mtx);
}
}
mtx_unlock(&nfs_reqq_mtx);
mtx_unlock(&Giant); /* nfs_down -> tprintf */
callout_reset(&nfs_callout, nfs_ticks, nfs_timer, NULL);
}
/*
* 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;
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(req, &nfs_reqq, r_chain) {
mtx_lock(&req->r_mtx);
if (nmp != req->r_nmp || req->r_mrep != NULL ||
(req->r_flags & R_SOFTTERM)) {
mtx_unlock(&req->r_mtx);
continue;
}
nfs_softterm(req);
mtx_unlock(&req->r_mtx);
}
mtx_unlock(&nfs_reqq_mtx);
for (i = 0; i < 30; i++) {
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(req, &nfs_reqq, r_chain) {
if (nmp == req->r_nmp)
break;
}
mtx_unlock(&nfs_reqq_mtx);
if (req == NULL)
return (0);
mtx_lock(&Giant);
tsleep(&lbolt, PSOCK, "nfscancel", 0);
mtx_unlock(&Giant);
}
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)
{
KASSERT(mtx_owned(&rep->r_mtx), ("NFS req lock not owned !"));
rep->r_flags |= R_SOFTTERM;
if (rep->r_flags & R_SENT) {
rep->r_nmp->nm_sent -= NFS_CWNDSCALE;
rep->r_flags &= ~R_SENT;
}
/*
* Request terminated, wakeup the blocked process, so that we
* can return EINTR back.
*/
wakeup((caddr_t)rep);
}
/*
* Any signal that can interrupt an NFS operation in an intr mount
* should be added to this set. SIGSTOP and SIGKILL cannot be masked.
*/
int nfs_sig_set[] = {
SIGINT,
SIGTERM,
SIGHUP,
SIGKILL,
SIGSTOP,
SIGQUIT
};
/*
* Check to see if one of the signals in our subset is pending on
* the process (in an intr mount).
*/
static int
nfs_sig_pending(sigset_t set)
{
int i;
for (i = 0 ; i < sizeof(nfs_sig_set)/sizeof(int) ; i++)
if (SIGISMEMBER(set, nfs_sig_set[i]))
return (1);
return (0);
}
/*
* The set/restore sigmask functions are used to (temporarily) overwrite
* the process p_sigmask during an RPC call (for example). These are also
* used in other places in the NFS client that might tsleep().
*/
void
nfs_set_sigmask(struct thread *td, sigset_t *oldset)
{
sigset_t newset;
int i;
struct proc *p;
SIGFILLSET(newset);
if (td == NULL)
td = curthread; /* XXX */
p = td->td_proc;
/* Remove the NFS set of signals from newset */
PROC_LOCK(p);
mtx_lock(&p->p_sigacts->ps_mtx);
for (i = 0 ; i < sizeof(nfs_sig_set)/sizeof(int) ; i++) {
/*
* But make sure we leave the ones already masked
* by the process, ie. remove the signal from the
* temporary signalmask only if it wasn't already
* in p_sigmask.
*/
if (!SIGISMEMBER(td->td_sigmask, nfs_sig_set[i]) &&
!SIGISMEMBER(p->p_sigacts->ps_sigignore, nfs_sig_set[i]))
SIGDELSET(newset, nfs_sig_set[i]);
}
mtx_unlock(&p->p_sigacts->ps_mtx);
PROC_UNLOCK(p);
kern_sigprocmask(td, SIG_SETMASK, &newset, oldset, 0);
}
void
nfs_restore_sigmask(struct thread *td, sigset_t *set)
{
if (td == NULL)
td = curthread; /* XXX */
kern_sigprocmask(td, SIG_SETMASK, set, NULL, 0);
}
/*
* NFS wrapper to msleep(), that shoves a new p_sigmask and restores the
* old one after msleep() returns.
*/
int
nfs_msleep(struct thread *td, void *ident, struct mtx *mtx, int priority, char *wmesg, int timo)
{
sigset_t oldset;
int error;
struct proc *p;
if ((priority & PCATCH) == 0)
return msleep(ident, mtx, priority, wmesg, timo);
if (td == NULL)
td = curthread; /* XXX */
nfs_set_sigmask(td, &oldset);
error = msleep(ident, mtx, priority, wmesg, timo);
nfs_restore_sigmask(td, &oldset);
p = td->td_proc;
return (error);
}
/*
* 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;
int error = 0;
if ((nmp->nm_flag & NFSMNT_NFSV4) != 0)
return nfs4_sigintr(nmp, rep, td);
if (rep) {
mtx_lock(&rep->r_mtx);
if (rep->r_flags & R_SOFTTERM) {
mtx_unlock(&rep->r_mtx);
error = EIO;
goto out;
} else
mtx_unlock(&rep->r_mtx);
}
/* Terminate all requests while attempting a forced unmount. */
if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF) {
error = EIO;
goto out;
}
if (!(nmp->nm_flag & NFSMNT_INT))
goto out;
if (td == NULL)
return (0);
p = td->td_proc;
PROC_LOCK(p);
tmpset = p->p_siglist;
SIGSETNAND(tmpset, td->td_sigmask);
mtx_lock(&p->p_sigacts->ps_mtx);
SIGSETNAND(tmpset, p->p_sigacts->ps_sigignore);
mtx_unlock(&p->p_sigacts->ps_mtx);
if (SIGNOTEMPTY(p->p_siglist) && nfs_sig_pending(tmpset)) {
PROC_UNLOCK(p);
return (EINTR);
}
PROC_UNLOCK(p);
return (0);
out:
return(error);
}
/*
* 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 error, slpflag = 0, slptimeo = 0;
td = rep->r_td;
mtx_lock(&rep->r_nmp->nm_mtx);
if (rep->r_nmp->nm_flag & NFSMNT_INT)
slpflag = PCATCH;
while (*statep & NFSSTA_SNDLOCK) {
error = nfs_sigintr(rep->r_nmp, rep, td);
if (error) {
mtx_unlock(&rep->r_nmp->nm_mtx);
return (error);
}
*statep |= NFSSTA_WANTSND;
(void) msleep(statep, &rep->r_nmp->nm_mtx,
slpflag | (PZERO - 1), "nfsndlck", slptimeo);
if (slpflag == PCATCH) {
slpflag = 0;
slptimeo = 2 * hz;
}
}
*statep |= NFSSTA_SNDLOCK;
mtx_unlock(&rep->r_nmp->nm_mtx);
return (0);
}
/*
* Unlock the stream socket for others.
*/
void
nfs_sndunlock(struct nfsreq *rep)
{
int *statep = &rep->r_nmp->nm_state;
mtx_lock(&rep->r_nmp->nm_mtx);
if ((*statep & NFSSTA_SNDLOCK) == 0)
panic("nfs sndunlock");
*statep &= ~NFSSTA_SNDLOCK;
if (*statep & NFSSTA_WANTSND) {
*statep &= ~NFSSTA_WANTSND;
wakeup(statep);
}
mtx_unlock(&rep->r_nmp->nm_mtx);
}
/*
* 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 int
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_DONTWAIT, MT_DATA);
if (n == NULL)
return (ENOMEM);
if (m->m_len >= MINCLSIZE) {
MCLGET(n, M_DONTWAIT);
if (n->m_ext.ext_buf == NULL) {
m_freem(n);
return (ENOMEM);
}
}
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;
}
return (0);
}
static int
nfs_msg(struct thread *td, const char *server, const char *msg, int error)
{
struct proc *p;
GIANT_REQUIRED; /* tprintf */
p = td ? td->td_proc : NULL;
if (error) {
tprintf(p, LOG_INFO, "nfs server %s: %s, error %d\n", server,
msg, error);
} else {
tprintf(p, LOG_INFO, "nfs server %s: %s\n", server, msg);
}
return (0);
}
void
nfs_down(rep, nmp, td, msg, error, flags)
struct nfsreq *rep;
struct nfsmount *nmp;
struct thread *td;
const char *msg;
int error, flags;
{
GIANT_REQUIRED; /* nfs_msg */
if (nmp == NULL)
return;
if ((flags & NFSSTA_TIMEO) && !(nmp->nm_state & NFSSTA_TIMEO)) {
vfs_event_signal(&nmp->nm_mountp->mnt_stat.f_fsid,
VQ_NOTRESP, 0);
nmp->nm_state |= NFSSTA_TIMEO;
}
#ifdef NFSSTA_LOCKTIMEO
if ((flags & NFSSTA_LOCKTIMEO) && !(nmp->nm_state & NFSSTA_LOCKTIMEO)) {
vfs_event_signal(&nmp->nm_mountp->mnt_stat.f_fsid,
VQ_NOTRESPLOCK, 0);
nmp->nm_state |= NFSSTA_LOCKTIMEO;
}
#endif
mtx_lock(&rep->r_mtx);
if (rep)
rep->r_flags |= R_TPRINTFMSG;
mtx_unlock(&rep->r_mtx);
nfs_msg(td, nmp->nm_mountp->mnt_stat.f_mntfromname, msg, error);
}
void
nfs_up(rep, nmp, td, msg, flags)
struct nfsreq *rep;
struct nfsmount *nmp;
struct thread *td;
const char *msg;
int flags;
{
GIANT_REQUIRED; /* nfs_msg */
if (nmp == NULL)
return;
mtx_lock(&rep->r_mtx);
if ((rep == NULL) || (rep->r_flags & R_TPRINTFMSG) != 0)
nfs_msg(td, nmp->nm_mountp->mnt_stat.f_mntfromname, msg, 0);
mtx_unlock(&rep->r_mtx);
if ((flags & NFSSTA_TIMEO) && (nmp->nm_state & NFSSTA_TIMEO)) {
nmp->nm_state &= ~NFSSTA_TIMEO;
vfs_event_signal(&nmp->nm_mountp->mnt_stat.f_fsid,
VQ_NOTRESP, 1);
}
#ifdef NFSSTA_LOCKTIMEO
if ((flags & NFSSTA_LOCKTIMEO) && (nmp->nm_state & NFSSTA_LOCKTIMEO)) {
nmp->nm_state &= ~NFSSTA_LOCKTIMEO;
vfs_event_signal(&nmp->nm_mountp->mnt_stat.f_fsid,
VQ_NOTRESPLOCK, 1);
}
#endif
}
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