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freebsd-dev/sys/nfsclient/nfs_socket.c
Paul Saab 7a5147540a Fix for a potential NFS client race where shared data is updated from 
base context as well as the socket callback.

Submitted by:	Mohan Srinivasan
2005-02-18 23:41:39 +00:00

1698 lines
44 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
/*
* 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;
static int nfs_reconnects;
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");
/*
* 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);
static void wakeup_nfsreq(struct nfsreq *req);
extern struct mtx nfs_reqq_mtx;
extern struct mtx nfs_reply_mtx;
/*
* 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_ASSERT_GIANT();
if (nmp->nm_sotype == SOCK_STREAM) {
mtx_lock(&nmp->nm_nfstcpstate.mtx);
nmp->nm_nfstcpstate.flags |= NFS_TCP_EXPECT_RPCMARKER;
nmp->nm_nfstcpstate.rpcresid = 0;
mtx_unlock(&nmp->nm_nfstcpstate.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.
*/
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.
*/
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;
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;
sosetopt(so, &sopt);
}
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;
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;
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);
/* 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_reconnects++;
nfs_disconnect(nmp);
while ((error = nfs_connect(nmp, rep)) != 0) {
if (error == ERESTART)
error = EINTR;
if (error == EIO || error == EINTR)
return (error);
(void) tsleep(&lbolt, PSOCK, "nfscon", 0);
}
/*
* 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
* the re-transmit the request.
*/
mtx_lock(&nmp->nm_nfstcpstate.mtx);
nmp->nm_nfstcpstate.flags &= ~NFS_TCP_FORCE_RECONNECT;
mtx_unlock(&nmp->nm_nfstcpstate.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)
rp->r_flags |= R_MUSTRESEND;
}
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();
if (nmp->nm_so) {
so = nmp->nm_so;
nmp->nm_so = NULL;
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);
}
}
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_ASSERT_GIANT();
KASSERT(rep, ("nfs_send: called with rep == NULL"));
error = nfs_sigintr(rep->r_nmp, rep, rep->r_td);
if (error) {
m_freem(top);
return (error);
}
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) {
/*
* 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
rep->r_flags |= R_MUSTRESEND;
/*
* Handle any recoverable (soft) socket errors here. (?)
*/
if (error != EINTR && error != ERESTART && error != EIO &&
error != EWOULDBLOCK && error != EPIPE)
error = 0;
}
return (error);
}
int nfs_mrep_before_tsleep = 0;
int
nfs_reply(struct nfsreq *rep)
{
register struct socket *so;
register struct mbuf *m;
int error, sotype, slpflag;
NET_ASSERT_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)
return (error);
tryagain:
if (rep->r_mrep) {
nfs_sndunlock(rep);
return (0);
}
if (rep->r_flags & R_SOFTTERM) {
nfs_sndunlock(rep);
return (EINTR);
}
so = rep->r_nmp->nm_so;
mtx_lock(&rep->r_nmp->nm_nfstcpstate.mtx);
if (!so ||
(rep->r_nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT)) {
mtx_unlock(&rep->r_nmp->nm_nfstcpstate.mtx);
error = nfs_reconnect(rep);
if (error) {
nfs_sndunlock(rep);
return (error);
}
goto tryagain;
} else
mtx_unlock(&rep->r_nmp->nm_nfstcpstate.mtx);
while (rep->r_flags & R_MUSTRESEND) {
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);
return (error);
}
goto tryagain;
}
}
nfs_sndunlock(rep);
}
slpflag = 0;
if (rep->r_nmp->nm_flag & NFSMNT_INT)
slpflag = PCATCH;
mtx_lock(&nfs_reply_mtx);
if (rep->r_mrep != NULL) {
/*
* This is a very rare race, but it does occur. The reply
* could come in and the wakeup could happen before the
* process tsleeps(). Blocking here without checking for
* this results in a missed wakeup(), blocking this request
* forever. The 2 reasons why this could happen are a context
* switch in the stack after the request is sent out, or heavy
* interrupt activity pinning down the process within the window.
* (after the request is sent).
*/
mtx_unlock(&nfs_reply_mtx);
nfs_mrep_before_tsleep++;
return (0);
}
error = msleep((caddr_t)rep, &nfs_reply_mtx,
slpflag | (PZERO - 1), "nfsreq", 0);
mtx_unlock(&nfs_reply_mtx);
if (error == EINTR || error == ERESTART)
/* NFS operations aren't restartable. Map ERESTART to EINTR */
return (EINTR);
if (rep->r_flags & R_SOFTTERM)
/* Request was terminated because we exceeded the retries (soft mount) */
return (ETIMEDOUT);
if (sotype == SOCK_STREAM) {
mtx_lock(&rep->r_nmp->nm_nfstcpstate.mtx);
if (((rep->r_nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT) ||
(rep->r_flags & R_MUSTRESEND))) {
mtx_unlock(&rep->r_nmp->nm_nfstcpstate.mtx);
error = nfs_sndlock(rep);
if (error)
return (error);
goto tryagain;
} else
mtx_unlock(&rep->r_nmp->nm_nfstcpstate.mtx);
}
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;
register int32_t t1;
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) {
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, wake up requestor.
*/
if (rep == 0) {
nfsstats.rpcunexpected++;
m_freem(mrep);
} else
wakeup_nfsreq(rep);
mtx_unlock(&nfs_reqq_mtx);
}
/*
* The wakeup of the requestor should be done under the mutex
* to avoid potential missed wakeups.
*/
static void
wakeup_nfsreq(struct nfsreq *req)
{
mtx_lock(&nfs_reply_mtx);
wakeup((caddr_t)req);
mtx_unlock(&nfs_reply_mtx);
}
static void
nfs_mark_for_reconnect(struct nfsmount *nmp)
{
struct nfsreq *rp;
mtx_lock(&nmp->nm_nfstcpstate.mtx);
nmp->nm_nfstcpstate.flags |= NFS_TCP_FORCE_RECONNECT;
mtx_unlock(&nmp->nm_nfstcpstate.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)
wakeup_nfsreq(rp);
}
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_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 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_nfstcpstate.mtx);
if (nmp->nm_nfstcpstate.flags & NFS_TCP_FORCE_RECONNECT) {
mtx_unlock(&nmp->nm_nfstcpstate.mtx);
return;
} else
mtx_unlock(&nmp->nm_nfstcpstate.mtx);
auio.uio_td = curthread;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_READ;
for ( ; ; ) {
if (nmp->nm_nfstcpstate.flags & NFS_TCP_EXPECT_RPCMARKER) {
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 (auio.uio_resid > 0) {
log(LOG_ERR,
"nfs/tcp clnt: Peer closed connection, tearing down TCP connection\n");
} else {
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");
len = ntohl(*mtod(mp, u_int32_t *)) & ~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;
}
nmp->nm_nfstcpstate.rpcresid = len;
nmp->nm_nfstcpstate.flags &= ~(NFS_TCP_EXPECT_RPCMARKER);
}
/*
* Processed RPC marker or no RPC marker to process.
* Pull in and process data.
*/
if (nmp->nm_nfstcpstate.rpcresid > 0) {
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 (auio.uio_resid > 0) {
log(LOG_ERR,
"nfs/tcp clnt: Peer closed connection, tearing down TCP connection\n");
} else {
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");
nmp->nm_nfstcpstate.rpcresid = 0;
nmp->nm_nfstcpstate.flags |= NFS_TCP_EXPECT_RPCMARKER;
/* We got the entire RPC reply. Match XIDs and wake up requestor */
nfs_clnt_match_xid(so, nmp, mp);
}
}
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
*/
/* 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;
struct timeval now;
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);
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);
rep->r_mrep = rep->r_md = NULL;
rep->r_nmp = nmp;
rep->r_vp = vp;
rep->r_td = td;
rep->r_procnum = procnum;
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, &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();
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.
*/
if (nmp->nm_so && (nmp->nm_sotype != SOCK_DGRAM ||
(nmp->nm_flag & NFSMNT_DUMBTIMR) ||
nmp->nm_sent < nmp->nm_cwnd)) {
splx(s);
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);
if (!error && (rep->r_flags & R_MUSTRESEND) == 0) {
nmp->nm_sent += NFS_CWNDSCALE;
rep->r_flags |= R_SENT;
}
mtx_unlock(&nfs_reqq_mtx);
} 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();
mtx_lock(&nfs_reqq_mtx);
TAILQ_REMOVE(&nfs_reqq, rep, r_chain);
if (TAILQ_EMPTY(&nfs_reqq))
callout_stop(&nfs_callout);
mtx_unlock(&nfs_reqq_mtx);
splx(s);
/*
* Decrement the outstanding request count.
*/
mtx_lock(&nfs_reqq_mtx);
if (rep->r_flags & R_SENT) {
rep->r_flags &= ~R_SENT; /* paranoia */
nmp->nm_sent -= NFS_CWNDSCALE;
}
mtx_unlock(&nfs_reqq_mtx);
/*
* If there was a successful reply and a tprintf msg.
* tprintf a response.
*/
if (!error)
nfs_up(rep, nmp, rep->r_td, "is alive again", NFSSTA_TIMEO);
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);
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);
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).
*
* XXX -
* For now, since we don't register MPSAFE callouts for the NFS client -
* softclock() acquires Giant before calling us. That prevents req entries
* from being removed from the list (from nfs_request()). But we still
* acquire the nfs reqq mutex to make sure the state of individual req
* entries is not modified from RPC reply handling (from socket callback)
* while nfs_timer is walking the list of reqs.
* 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()). This won't work
* when we move to fine grained locking for NFS. When we get to that point,
* a rewrite of nfs_timer() will be needed.
*/
void
nfs_timer(void *arg)
{
struct nfsreq *rep;
struct mbuf *m;
struct socket *so;
struct nfsmount *nmp;
int timeo;
int s, error;
struct timeval now;
getmicrouptime(&now);
s = splnet();
mtx_lock(&nfs_reqq_mtx);
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))
continue;
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) {
rep->r_lastmsg = now.tv_sec;
nfs_down(rep, nmp, rep->r_td, "not responding",
0, NFSSTA_TIMEO);
#if 0
if (!(nmp->nm_state & NFSSTA_MOUNTED)) {
/* we're not yet completely mounted and */
/* we can't complete an RPC, so we fail */
nfsstats.rpctimeouts++;
nfs_softterm(rep);
continue;
}
#endif
}
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++;
}
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))){
mtx_unlock(&nfs_reqq_mtx);
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);
mtx_lock(&nfs_reqq_mtx);
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(&nfs_reqq_mtx);
splx(s);
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, s;
s = splnet();
mtx_lock(&nfs_reqq_mtx);
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);
}
mtx_unlock(&nfs_reqq_mtx);
splx(s);
for (i = 0; i < 30; i++) {
s = splnet();
mtx_lock(&nfs_reqq_mtx);
TAILQ_FOREACH(req, &nfs_reqq, r_chain) {
if (nmp == req->r_nmp)
break;
}
mtx_unlock(&nfs_reqq_mtx);
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;
}
/*
* Request terminated, wakeup the blocked process, so that we
* can return EINTR back.
*/
wakeup_nfsreq(rep);
}
/*
* Any signal that can interrupt an NFS operation in an intr mount
* should be added to this set.
*/
int nfs_sig_set[] = {
SIGINT,
SIGTERM,
SIGHUP,
SIGKILL,
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);
}
/*
* NFS wrapper to tsleep(), that shoves a new p_sigmask and restores the
* old one after tsleep() returns.
*/
int
nfs_tsleep(struct thread *td, void *ident, int priority, char *wmesg, int timo)
{
sigset_t oldset;
int error;
struct proc *p;
if ((priority & PCATCH) == 0)
return tsleep(ident, priority, wmesg, timo);
if (td == NULL)
td = curthread; /* XXX */
nfs_set_sigmask(td, &oldset);
error = tsleep(ident, 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;
if ((nmp->nm_flag & NFSMNT_NFSV4) != 0)
return nfs4_sigintr(nmp, rep, td);
if (rep && (rep->r_flags & R_SOFTTERM))
return (EIO);
/* Terminate all requests while attempting a forced unmount. */
if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)
return (EIO);
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);
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);
}
/*
* 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;
if (rep->r_nmp->nm_flag & NFSMNT_INT)
slpflag = PCATCH;
while (*statep & NFSSTA_SNDLOCK) {
error = nfs_sigintr(rep->r_nmp, rep, td);
if (error)
return (error);
*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);
}
}
/*
* 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.
*
* XXX - This still looks buggy. If there are multiple mbufs in the mbuf chain
* passed in that are unaligned, the first loop will allocate multiple new
* mbufs. But then, it doesn't seem to chain these together. So, if there are
* multiple unaligned mbufs, we're looking at a pretty serious mbuf leak.
* But, this has been how it is, perhaps the misalignment only happens in the head
* of the chain.
*/
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;
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;
{
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
if (rep)
rep->r_flags |= R_TPRINTFMSG;
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;
{
if (nmp == NULL)
return;
if ((rep == NULL) || (rep->r_flags & R_TPRINTFMSG) != 0)
nfs_msg(td, nmp->nm_mountp->mnt_stat.f_mntfromname, msg, 0);
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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