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freebsd-skq/sys/nfsserver/nfs_syscalls.c
rwatson 9cd72a8223 The socket code upcalls into the NFS server using the so_upcall 
mechanism so that early processing on mbufs can be performed before
a context switch to the NFS server threads.  Because of this, if
the socket code is running without Giant, the NFS server also needs
to be able to run the upcall code without relying on the presence on
Giant.  This change modifies the NFS server to run using a "giant
code lock" covering operation of the whole subsystem.  Work is in
progress to move to data-based locking as part of the NFSv4 server
changes.

Introduce an NFS server subsystem lock, 'nfsd_mtx', and a set of
macros to operate on the lock:

  NFSD_LOCK_ASSERT()    Assert nfsd_mtx owned by current thread
  NFSD_UNLOCK_ASSERT()  Assert nfsd_mtx not owned by current thread
  NFSD_LOCK_DONTCARE()  Advisory: this function doesn't care
  NFSD_LOCK()           Lock nfsd_mtx
  NFSD_UNLOCK()         Unlock nfsd_mtx

Constify a number of global variables/structures in the NFS server
code, as they are not modified and contain constants only:

  nfsrvv2_procid       nfsrv_nfsv3_procid      nonidempotent
  nfsv2_repstat        nfsv2_type              nfsrv_nfsv3_procid
  nfsrvv2_procid       nfsrv_v2errmap          nfsv3err_null
  nfsv3err_getattr     nfsv3err_setattr        nfsv3err_lookup
  nfsv3err_access      nfsv3err_readlink       nfsv3err_read
  nfsv3err_write       nfsv3err_create         nfsv3err_mkdir
  nfsv3err_symlink     nfsv3err_mknod          nfsv3err_remove
  nfsv3err_rmdir       nfsv3err_rename         nfsv3err_link
  nfsv3err_readdir     nfsv3err_readdirplus    nfsv3err_fsstat
  nfsv3err_fsinfo      nfsv3err_pathconf       nfsv3err_commit
  nfsrv_v3errmap

There are additional structures that should be constified but due
to their being passed into general purpose functions without const
arguments, I have not yet converted.

In general, acquire nfsd_mtx when accessing any of the global NFS
structures, including struct nfssvc_sock, struct nfsd, struct
nfsrv_descript.

Release nfsd_mtx whenever calling into VFS, and acquire Giant for
calls into VFS.  Giant is not required for any part of the
operation of the NFS server with the exception of calls into VFS.
Giant will never by acquired in the upcall code path.  However, it
may operate entirely covered by Giant, or not.  If debug.mpsafenet
is set to 0, the system calls will acquire Giant across all
operations, and the upcall will assert Giant.  As such, by default,
this enables locking and allows us to test assertions, but should not
cause any substantial new amount of code to be run without Giant.
Bugs should manifest in the form of lock assertion failures for now.

This approach is similar (but not identical) to modifications to the
BSD/OS NFS server code snapshot provided by BSDi as part of their
SMPng snapshot.  The strategy is almost the same (single lock over
the NFS server), but differs in the following ways:

- Our NFS client and server code bases don't overlap, which means
  both fewer bugs and easier locking (thanks Peter!).  Also means
  NFSD_*() as opposed to NFS_*().

- We make broad use of assertions, whereas the BSD/OS code does not.

- Made slightly different choices about how to handle macros building
  packets but operating with side effects.

- We acquire Giant only when entering VFS from the NFS server daemon
  threads.

- Serious bugs in BSD/OS implementation corrected -- the snapshot we
  received was clearly a work in progress.

Based on ideas from:	BSDi SMPng Snapshot
Reviewed by:		rick@snowhite.cis.uoguelph.ca
Extensive testing by:	kris
2004-05-24 04:06:14 +00:00

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/*
* Copyright (c) 1989, 1993
* 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_syscalls.c 8.5 (Berkeley) 3/30/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet6.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/vnode.h>
#include <sys/mac.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/namei.h>
#include <sys/fcntl.h>
#include <sys/lockf.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#ifdef INET6
#include <net/if.h>
#include <netinet6/in6_var.h>
#endif
#include <nfs/xdr_subs.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfsserver/nfs.h>
#include <nfsserver/nfsm_subs.h>
#include <nfsserver/nfsrvcache.h>
static MALLOC_DEFINE(M_NFSSVC, "NFS srvsock", "Nfs server structure");
MALLOC_DEFINE(M_NFSRVDESC, "NFSV3 srvdesc", "NFS server socket descriptor");
MALLOC_DEFINE(M_NFSD, "NFS daemon", "Nfs server daemon structure");
#define TRUE 1
#define FALSE 0
SYSCTL_DECL(_vfs_nfsrv);
int nfsd_waiting = 0;
int nfsrv_numnfsd = 0;
static int notstarted = 1;
static int nfs_privport = 0;
SYSCTL_INT(_vfs_nfsrv, NFS_NFSPRIVPORT, nfs_privport, CTLFLAG_RW,
&nfs_privport, 0, "");
SYSCTL_INT(_vfs_nfsrv, OID_AUTO, gatherdelay, CTLFLAG_RW,
&nfsrvw_procrastinate, 0, "");
SYSCTL_INT(_vfs_nfsrv, OID_AUTO, gatherdelay_v3, CTLFLAG_RW,
&nfsrvw_procrastinate_v3, 0, "");
static int nfssvc_addsock(struct file *, struct sockaddr *,
struct thread *);
static void nfsrv_zapsock(struct nfssvc_sock *slp);
static int nfssvc_nfsd(struct thread *);
/*
* NFS server system calls
*/
/*
* Nfs server psuedo system call for the nfsd's
* Based on the flag value it either:
* - adds a socket to the selection list
* - remains in the kernel as an nfsd
* - remains in the kernel as an nfsiod
* For INET6 we suppose that nfsd provides only IN6P_IPV6_V6ONLY sockets
* and that mountd provides
* - sockaddr with no IPv4-mapped addresses
* - mask for both INET and INET6 families if there is IPv4-mapped overlap
*/
#ifndef _SYS_SYSPROTO_H_
struct nfssvc_args {
int flag;
caddr_t argp;
};
#endif
/*
* MPSAFE
*/
int
nfssvc(struct thread *td, struct nfssvc_args *uap)
{
struct file *fp;
struct sockaddr *nam;
struct nfsd_args nfsdarg;
int error;
#ifdef MAC
error = mac_check_system_nfsd(td->td_ucred);
if (error)
return (error);
#endif
error = suser(td);
if (error)
return (error);
NET_LOCK_GIANT();
NFSD_LOCK();
while (nfssvc_sockhead_flag & SLP_INIT) {
nfssvc_sockhead_flag |= SLP_WANTINIT;
(void) msleep(&nfssvc_sockhead, &nfsd_mtx, PSOCK,
"nfsd init", 0);
}
NFSD_UNLOCK();
if (uap->flag & NFSSVC_ADDSOCK) {
error = copyin(uap->argp, (caddr_t)&nfsdarg, sizeof(nfsdarg));
if (error)
goto done2;
if ((error = fget(td, nfsdarg.sock, &fp)) != 0)
goto done2;
if (fp->f_type != DTYPE_SOCKET) {
fdrop(fp, td);
goto done2;
}
/*
* Get the client address for connected sockets.
*/
if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
nam = NULL;
else {
error = getsockaddr(&nam, nfsdarg.name,
nfsdarg.namelen);
if (error) {
fdrop(fp, td);
goto done2;
}
}
error = nfssvc_addsock(fp, nam, td);
fdrop(fp, td);
} else if (uap->flag & NFSSVC_NFSD) {
error = nfssvc_nfsd(td);
} else {
error = ENXIO;
}
if (error == EINTR || error == ERESTART)
error = 0;
done2:
NET_UNLOCK_GIANT();
return (error);
}
/*
* Adds a socket to the list for servicing by nfsds.
*/
static int
nfssvc_addsock(struct file *fp, struct sockaddr *mynam, struct thread *td)
{
int siz;
struct nfssvc_sock *slp;
struct socket *so;
int error, s;
NET_ASSERT_GIANT();
so = fp->f_data;
#if 0
/*
* XXXRW: If this code is ever enabled, there's a race when running
* MPSAFE.
*/
tslp = NULL;
/*
* Add it to the list, as required.
*/
if (so->so_proto->pr_protocol == IPPROTO_UDP) {
tslp = nfs_udpsock;
if (tslp->ns_flag & SLP_VALID) {
if (mynam != NULL)
FREE(mynam, M_SONAME);
return (EPERM);
}
}
#endif
if (so->so_type == SOCK_STREAM)
siz = NFS_MAXPACKET + sizeof (u_long);
else
siz = NFS_MAXPACKET;
error = soreserve(so, siz, siz);
if (error) {
if (mynam != NULL)
FREE(mynam, M_SONAME);
return (error);
}
/*
* Set protocol specific options { for now TCP only } and
* reserve some space. For datagram sockets, this can get called
* repeatedly for the same socket, but that isn't harmful.
*/
if (so->so_type == SOCK_STREAM) {
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);
}
so->so_rcv.sb_flags &= ~SB_NOINTR;
so->so_rcv.sb_timeo = 0;
so->so_snd.sb_flags &= ~SB_NOINTR;
so->so_snd.sb_timeo = 0;
slp = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC,
M_WAITOK | M_ZERO);
STAILQ_INIT(&slp->ns_rec);
NFSD_LOCK();
TAILQ_INSERT_TAIL(&nfssvc_sockhead, slp, ns_chain);
slp->ns_so = so;
slp->ns_nam = mynam;
fhold(fp);
slp->ns_fp = fp;
/*
* XXXRW: Socket locking here?
*/
s = splnet();
so->so_upcallarg = (caddr_t)slp;
so->so_upcall = nfsrv_rcv;
so->so_rcv.sb_flags |= SB_UPCALL;
slp->ns_flag = (SLP_VALID | SLP_NEEDQ);
nfsrv_wakenfsd(slp);
splx(s);
NFSD_UNLOCK();
return (0);
}
/*
* Called by nfssvc() for nfsds. Just loops around servicing rpc requests
* until it is killed by a signal.
*/
static int
nfssvc_nfsd(struct thread *td)
{
int siz;
struct nfssvc_sock *slp;
struct nfsd *nfsd;
struct nfsrv_descript *nd = NULL;
struct mbuf *m, *mreq;
int error = 0, cacherep, s, sotype, writes_todo;
int procrastinate;
u_quad_t cur_usec;
NET_ASSERT_GIANT();
#ifndef nolint
cacherep = RC_DOIT;
writes_todo = 0;
#endif
nfsd = (struct nfsd *)
malloc(sizeof (struct nfsd), M_NFSD, M_WAITOK | M_ZERO);
s = splnet();
NFSD_LOCK();
nfsd->nfsd_td = td;
TAILQ_INSERT_TAIL(&nfsd_head, nfsd, nfsd_chain);
nfsrv_numnfsd++;
/*
* Loop getting rpc requests until SIGKILL.
*/
for (;;) {
if ((nfsd->nfsd_flag & NFSD_REQINPROG) == 0) {
while (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) == 0) {
nfsd->nfsd_flag |= NFSD_WAITING;
nfsd_waiting++;
error = msleep(nfsd, &nfsd_mtx,
PSOCK | PCATCH, "-", 0);
nfsd_waiting--;
if (error)
goto done;
}
if (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) != 0) {
TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
if ((slp->ns_flag & (SLP_VALID | SLP_DOREC))
== (SLP_VALID | SLP_DOREC)) {
slp->ns_flag &= ~SLP_DOREC;
slp->ns_sref++;
nfsd->nfsd_slp = slp;
break;
}
}
if (slp == NULL)
nfsd_head_flag &= ~NFSD_CHECKSLP;
}
if ((slp = nfsd->nfsd_slp) == NULL)
continue;
if (slp->ns_flag & SLP_VALID) {
if (slp->ns_flag & SLP_DISCONN)
nfsrv_zapsock(slp);
else if (slp->ns_flag & SLP_NEEDQ) {
slp->ns_flag &= ~SLP_NEEDQ;
(void) nfs_slplock(slp, 1);
NFSD_UNLOCK();
nfsrv_rcv(slp->ns_so, (caddr_t)slp,
M_TRYWAIT);
NFSD_LOCK();
nfs_slpunlock(slp);
}
error = nfsrv_dorec(slp, nfsd, &nd);
cur_usec = nfs_curusec();
if (error && LIST_FIRST(&slp->ns_tq) &&
LIST_FIRST(&slp->ns_tq)->nd_time <= cur_usec) {
error = 0;
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
nfsd->nfsd_flag |= NFSD_REQINPROG;
}
} else {
error = 0;
slp = nfsd->nfsd_slp;
}
if (error || (slp->ns_flag & SLP_VALID) == 0) {
if (nd) {
free((caddr_t)nd, M_NFSRVDESC);
nd = NULL;
}
nfsd->nfsd_slp = NULL;
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsrv_slpderef(slp);
continue;
}
splx(s);
sotype = slp->ns_so->so_type;
if (nd) {
getmicrotime(&nd->nd_starttime);
if (nd->nd_nam2)
nd->nd_nam = nd->nd_nam2;
else
nd->nd_nam = slp->ns_nam;
/*
* Check to see if authorization is needed.
*/
cacherep = nfsrv_getcache(nd, &mreq);
if (nfs_privport) {
/* Check if source port is privileged */
u_short port;
struct sockaddr *nam = nd->nd_nam;
struct sockaddr_in *sin;
sin = (struct sockaddr_in *)nam;
/*
* INET/INET6 - same code:
* sin_port and sin6_port are at same offset
*/
port = ntohs(sin->sin_port);
if (port >= IPPORT_RESERVED &&
nd->nd_procnum != NFSPROC_NULL) {
#if defined(INET6) && defined(KLD_MODULE)
/* do not use ip6_sprintf: the nfs module should work without INET6 */
char b6[INET6_ADDRSTRLEN];
#define ip6_sprintf(a) \
(sprintf(b6, "%x:%x:%x:%x:%x:%x:%x:%x", \
(a)->s6_addr16[0], (a)->s6_addr16[1], \
(a)->s6_addr16[2], (a)->s6_addr16[3], \
(a)->s6_addr16[4], (a)->s6_addr16[5], \
(a)->s6_addr16[6], (a)->s6_addr16[7]), \
b6)
#endif
nd->nd_procnum = NFSPROC_NOOP;
nd->nd_repstat = (NFSERR_AUTHERR | AUTH_TOOWEAK);
cacherep = RC_DOIT;
printf("NFS request from unprivileged port (%s:%d)\n",
#ifdef INET6
sin->sin_family == AF_INET6 ?
ip6_sprintf(&satosin6(sin)->sin6_addr) :
#undef ip6_sprintf
#endif
inet_ntoa(sin->sin_addr), port);
}
}
}
/*
* Loop to get all the write rpc relies that have been
* gathered together.
*/
do {
switch (cacherep) {
case RC_DOIT:
if (nd && (nd->nd_flag & ND_NFSV3))
procrastinate = nfsrvw_procrastinate_v3;
else
procrastinate = nfsrvw_procrastinate;
if (writes_todo || (nd->nd_procnum == NFSPROC_WRITE &&
procrastinate > 0 && !notstarted))
error = nfsrv_writegather(&nd, slp,
nfsd->nfsd_td, &mreq);
else
error = (*(nfsrv3_procs[nd->nd_procnum]))(nd,
slp, nfsd->nfsd_td, &mreq);
if (mreq == NULL)
break;
if (error != 0 && error != NFSERR_RETVOID) {
nfsrvstats.srv_errs++;
nfsrv_updatecache(nd, FALSE, mreq);
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
break;
}
nfsrvstats.srvrpccnt[nd->nd_procnum]++;
nfsrv_updatecache(nd, TRUE, mreq);
nd->nd_mrep = NULL;
/* FALLTHROUGH */
case RC_REPLY:
NFSD_UNLOCK();
siz = m_length(mreq, NULL);
if (siz <= 0 || siz > NFS_MAXPACKET) {
printf("mbuf siz=%d\n",siz);
panic("Bad nfs svc reply");
}
m = mreq;
m->m_pkthdr.len = siz;
m->m_pkthdr.rcvif = NULL;
/*
* For stream protocols, prepend a Sun RPC
* Record Mark.
*/
if (sotype == SOCK_STREAM) {
M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
*mtod(m, u_int32_t *) = htonl(0x80000000 | siz);
}
NFSD_LOCK();
if (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)
(void) nfs_slplock(slp, 1);
if (slp->ns_flag & SLP_VALID) {
NFSD_UNLOCK();
NET_LOCK_GIANT();
error = nfsrv_send(slp->ns_so, nd->nd_nam2, m);
NET_UNLOCK_GIANT();
NFSD_LOCK();
} else {
error = EPIPE;
m_freem(m);
}
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
if (nd->nd_mrep)
m_freem(nd->nd_mrep);
if (error == EPIPE)
nfsrv_zapsock(slp);
if (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)
nfs_slpunlock(slp);
if (error == EINTR || error == ERESTART) {
free((caddr_t)nd, M_NFSRVDESC);
nfsrv_slpderef(slp);
s = splnet();
goto done;
}
break;
case RC_DROPIT:
m_freem(nd->nd_mrep);
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
break;
};
if (nd) {
FREE((caddr_t)nd, M_NFSRVDESC);
nd = NULL;
}
/*
* Check to see if there are outstanding writes that
* need to be serviced.
*/
cur_usec = nfs_curusec();
s = splsoftclock();
if (LIST_FIRST(&slp->ns_tq) &&
LIST_FIRST(&slp->ns_tq)->nd_time <= cur_usec) {
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
splx(s);
} while (writes_todo);
s = splnet();
if (nfsrv_dorec(slp, nfsd, &nd)) {
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsd->nfsd_slp = NULL;
nfsrv_slpderef(slp);
}
}
done:
TAILQ_REMOVE(&nfsd_head, nfsd, nfsd_chain);
splx(s);
free((caddr_t)nfsd, M_NFSD);
if (--nfsrv_numnfsd == 0)
nfsrv_init(TRUE); /* Reinitialize everything */
NFSD_UNLOCK();
return (error);
}
/*
* Shut down a socket associated with an nfssvc_sock structure.
* Should be called with the send lock set, if required.
* The trick here is to increment the sref at the start, so that the nfsds
* will stop using it and clear ns_flag at the end so that it will not be
* reassigned during cleanup.
*/
static void
nfsrv_zapsock(struct nfssvc_sock *slp)
{
struct nfsrv_descript *nwp, *nnwp;
struct socket *so;
struct file *fp;
struct nfsrv_rec *rec;
int s;
NET_ASSERT_GIANT();
NFSD_LOCK_ASSERT();
/*
* XXXRW: By clearing all flags, other threads/etc should ignore
* this slp and we can safely release nfsd_mtx so we can clean
* up the slp safely.
*/
slp->ns_flag &= ~SLP_ALLFLAGS;
fp = slp->ns_fp;
if (fp) {
NFSD_UNLOCK();
slp->ns_fp = NULL;
so = slp->ns_so;
so->so_rcv.sb_flags &= ~SB_UPCALL;
so->so_upcall = NULL;
so->so_upcallarg = NULL;
soshutdown(so, SHUT_RDWR);
closef(fp, NULL);
NFSD_LOCK();
if (slp->ns_nam)
FREE(slp->ns_nam, M_SONAME);
m_freem(slp->ns_raw);
while ((rec = STAILQ_FIRST(&slp->ns_rec)) != NULL) {
STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
if (rec->nr_address)
FREE(rec->nr_address, M_SONAME);
m_freem(rec->nr_packet);
free(rec, M_NFSRVDESC);
}
s = splsoftclock();
for (nwp = LIST_FIRST(&slp->ns_tq); nwp; nwp = nnwp) {
nnwp = LIST_NEXT(nwp, nd_tq);
LIST_REMOVE(nwp, nd_tq);
free((caddr_t)nwp, M_NFSRVDESC);
}
LIST_INIT(&slp->ns_tq);
splx(s);
}
}
/*
* Derefence a server socket structure. If it has no more references and
* is no longer valid, you can throw it away.
*/
void
nfsrv_slpderef(struct nfssvc_sock *slp)
{
NFSD_LOCK_ASSERT();
if (--(slp->ns_sref) == 0 && (slp->ns_flag & SLP_VALID) == 0) {
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
}
/*
* Lock a socket against others.
*
* XXXRW: Wait argument is always 1 in the caller. Replace with a real
* sleep lock?
*/
int
nfs_slplock(struct nfssvc_sock *slp, int wait)
{
int *statep = &slp->ns_solock;
NFSD_LOCK_ASSERT();
if (!wait && (*statep & NFSRV_SNDLOCK))
return(0); /* already locked, fail */
while (*statep & NFSRV_SNDLOCK) {
*statep |= NFSRV_WANTSND;
(void) msleep(statep, &nfsd_mtx, PZERO - 1, "nfsslplck", 0);
}
*statep |= NFSRV_SNDLOCK;
return (1);
}
/*
* Unlock the stream socket for others.
*/
void
nfs_slpunlock(struct nfssvc_sock *slp)
{
int *statep = &slp->ns_solock;
NFSD_LOCK_ASSERT();
if ((*statep & NFSRV_SNDLOCK) == 0)
panic("nfs slpunlock");
*statep &= ~NFSRV_SNDLOCK;
if (*statep & NFSRV_WANTSND) {
*statep &= ~NFSRV_WANTSND;
wakeup(statep);
}
}
/*
* Initialize the data structures for the server.
* Handshake with any new nfsds starting up to avoid any chance of
* corruption.
*/
void
nfsrv_init(int terminating)
{
struct nfssvc_sock *slp, *nslp;
NET_ASSERT_GIANT();
NFSD_LOCK_ASSERT();
if (nfssvc_sockhead_flag & SLP_INIT)
panic("nfsd init");
nfssvc_sockhead_flag |= SLP_INIT;
if (terminating) {
for (slp = TAILQ_FIRST(&nfssvc_sockhead); slp != NULL;
slp = nslp) {
nslp = TAILQ_NEXT(slp, ns_chain);
if (slp->ns_flag & SLP_VALID)
nfsrv_zapsock(slp);
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
nfsrv_cleancache(); /* And clear out server cache */
} else
nfs_pub.np_valid = 0;
TAILQ_INIT(&nfssvc_sockhead);
nfssvc_sockhead_flag &= ~SLP_INIT;
if (nfssvc_sockhead_flag & SLP_WANTINIT) {
nfssvc_sockhead_flag &= ~SLP_WANTINIT;
wakeup(&nfssvc_sockhead);
}
TAILQ_INIT(&nfsd_head);
nfsd_head_flag &= ~NFSD_CHECKSLP;
#if 0
nfs_udpsock = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
STAILQ_INIT(&nfs_udpsock->ns_rec);
TAILQ_INSERT_HEAD(&nfssvc_sockhead, nfs_udpsock, ns_chain);
nfs_cltpsock = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
STAILQ_INIT(&nfs_cltpsock->ns_rec);
TAILQ_INSERT_TAIL(&nfssvc_sockhead, nfs_cltpsock, ns_chain);
#endif
}
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