BSD 4_4 release
[unix-history] / usr / src / usr.sbin / amd / amd / srvr_nfs.c
/*
* Copyright (c) 1990 Jan-Simon Pendry
* Copyright (c) 1990 Imperial College of Science, Technology & Medicine
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry at Imperial College, London.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)srvr_nfs.c 8.1 (Berkeley) 6/6/93
*
* $Id: srvr_nfs.c,v 5.2.2.1 1992/02/09 15:09:06 jsp beta $
*
*/
/*
* NFS server modeling
*/
#include "am.h"
#include <netdb.h>
#include <rpc/pmap_prot.h>
#include "mount.h"
extern qelem nfs_srvr_list;
qelem nfs_srvr_list = { &nfs_srvr_list, &nfs_srvr_list };
typedef struct nfs_private {
u_short np_mountd; /* Mount daemon port number */
char np_mountd_inval; /* Port *may* be invalid */
int np_ping; /* Number of failed ping attempts */
time_t np_ttl; /* Time when server is thought dead */
int np_xid; /* RPC transaction id for pings */
int np_error; /* Error during portmap request */
} nfs_private;
static int np_xid; /* For NFS pings */
#define NPXID_ALLOC() (++np_xid)
/*#define NPXID_ALLOC() ((++np_xid&0x0fffffff) == 0 ? npxid_gc() : np_xid)*/
/*
* Number of pings allowed to fail before host is declared down
* - three-fifths of the allowed mount time...
#define MAX_ALLOWED_PINGS ((((ALLOWED_MOUNT_TIME + 5 * AM_PINGER - 1) * 3) / 5) / AM_PINGER)
*/
#define MAX_ALLOWED_PINGS (3 + /* for luck ... */ 1)
/*
* How often to ping when starting a new server
*/
#define FAST_NFS_PING 3
#if (FAST_NFS_PING * MAX_ALLOWED_PINGS) >= ALLOWED_MOUNT_TIME
#error: sanity check failed
/*
you cannot do things this way...
sufficient fast pings must be given the chance to fail
within the allowed mount time
*/
#endif /* (FAST_NFS_PING * MAX_ALLOWED_PINGS) >= ALLOWED_MOUNT_TIME */
static int ping_len;
static char ping_buf[sizeof(struct rpc_msg) + 32];
/*
* Flush any cached data
*/
void flush_srvr_nfs_cache P((void));
void flush_srvr_nfs_cache()
{
fserver *fs = 0;
ITER(fs, fserver, &nfs_srvr_list) {
nfs_private *np = (nfs_private *) fs->fs_private;
if (np) {
np->np_mountd_inval = TRUE;
np->np_error = -1;
}
}
}
/*
* Startup the NFS ping
*/
static void start_ping(P_void);
static void start_ping()
{
XDR ping_xdr;
struct rpc_msg ping_msg;
rpc_msg_init(&ping_msg, NFS_PROGRAM, NFS_VERSION, NFSPROC_NULL);
/*
* Create an XDR endpoint
*/
xdrmem_create(&ping_xdr, ping_buf, sizeof(ping_buf), XDR_ENCODE);
/*
* Create the NFS ping message
*/
if (!xdr_callmsg(&ping_xdr, &ping_msg)) {
plog(XLOG_ERROR, "Couldn't create ping RPC message");
going_down(3);
}
/*
* Find out how long it is
*/
ping_len = xdr_getpos(&ping_xdr);
/*
* Destroy the XDR endpoint - we don't need it anymore
*/
xdr_destroy(&ping_xdr);
}
/*
* Called when a portmap reply arrives
*/
/*ARGSUSED*/
static void got_portmap P((voidp pkt, int len, struct sockaddr_in *sa, struct sockaddr_in *ia, voidp idv, int done));
static void got_portmap(pkt, len, sa, ia, idv, done)
voidp pkt;
int len;
struct sockaddr_in *sa;
struct sockaddr_in *ia;
voidp idv;
int done;
{
fserver *fs2 = (fserver *) idv;
fserver *fs = 0;
/*
* Find which fileserver we are talking about
*/
ITER(fs, fserver, &nfs_srvr_list)
if (fs == fs2)
break;
if (fs == fs2) {
u_long port = 0; /* XXX - should be short but protocol is naff */
int error = done ? pickup_rpc_reply(pkt, len, (voidp) &port, xdr_u_long) : -1;
nfs_private *np = (nfs_private *) fs->fs_private;
if (!error && port) {
#ifdef DEBUG
dlog("got port (%d) for mountd on %s", port, fs->fs_host);
#endif /* DEBUG */
/*
* Grab the port number. Portmap sends back
* an unsigned long in native ordering, so it
* needs converting to a unsigned short in
* network ordering.
*/
np->np_mountd = htons((u_short) port);
np->np_mountd_inval = FALSE;
np->np_error = 0;
} else {
#ifdef DEBUG
dlog("Error fetching port for mountd on %s", fs->fs_host);
#endif /* DEBUG */
/*
* Almost certainly no mountd running on remote host
*/
np->np_error = error ? error : ETIMEDOUT;
}
if (fs->fs_flags & FSF_WANT)
wakeup_srvr(fs);
} else if (done) {
#ifdef DEBUG
dlog("Got portmap for old port request");
#endif /* DEBUG */
} else {
#ifdef DEBUG
dlog("portmap request timed out");
#endif /* DEBUG */
}
}
/*
* Obtain portmap information
*/
static int call_portmap P((fserver *fs, AUTH *auth, unsigned long prog, unsigned long vers, unsigned long prot));
static int call_portmap(fs, auth, prog, vers, prot)
fserver *fs;
AUTH *auth;
unsigned long prog, vers, prot;
{
struct rpc_msg pmap_msg;
int len;
char iobuf[UDPMSGSIZE];
int error;
struct pmap pmap;
rpc_msg_init(&pmap_msg, PMAPPROG, PMAPVERS, (unsigned long) 0);
pmap.pm_prog = prog;
pmap.pm_vers = vers;
pmap.pm_prot = prot;
pmap.pm_port = 0;
len = make_rpc_packet(iobuf, sizeof(iobuf), PMAPPROC_GETPORT,
&pmap_msg, (voidp) &pmap, xdr_pmap, auth);
if (len > 0) {
struct sockaddr_in sin;
bzero((voidp) &sin, sizeof(sin));
sin = *fs->fs_ip;
sin.sin_port = htons(PMAPPORT);
error = fwd_packet(RPC_XID_PORTMAP, (voidp) iobuf, len,
&sin, &sin, (voidp) fs, got_portmap);
} else {
error = -len;
}
return error;
}
static void nfs_keepalive P((fserver*));
static void recompute_portmap P((fserver *fs));
static void recompute_portmap(fs)
fserver *fs;
{
int error;
if (nfs_auth)
error = 0;
else
error = make_nfs_auth();
if (error) {
nfs_private *np = (nfs_private *) fs->fs_private;
np->np_error = error;
} else {
call_portmap(fs, nfs_auth, MOUNTPROG,
MOUNTVERS, (unsigned long) IPPROTO_UDP);
}
}
/*
* This is called when we get a reply to an RPC ping.
* The value of id was taken from the nfs_private
* structure when the ping was transmitted.
*/
/*ARGSUSED*/
static void nfs_pinged P((voidp pkt, int len, struct sockaddr_in *sp, struct sockaddr_in *tsp, voidp idv, int done));
static void nfs_pinged(pkt, len, sp, tsp, idv, done)
voidp pkt;
int len;
struct sockaddr_in *sp;
struct sockaddr_in *tsp;
voidp idv;
int done;
{
int xid = (int) idv;
fserver *fs;
#ifdef DEBUG
int found_map = 0;
#endif /* DEBUG */
if (!done)
return;
/*
* For each node...
*/
ITER(fs, fserver, &nfs_srvr_list) {
nfs_private *np = (nfs_private *) fs->fs_private;
if (np->np_xid == xid) {
/*
* Reset the ping counter.
* Update the keepalive timer.
* Log what happened.
*/
if (fs->fs_flags & FSF_DOWN) {
fs->fs_flags &= ~FSF_DOWN;
if (fs->fs_flags & FSF_VALID) {
srvrlog(fs, "is up");
} else {
if (np->np_ping > 1)
srvrlog(fs, "ok");
#ifdef DEBUG
else
srvrlog(fs, "starts up");
#endif
fs->fs_flags |= FSF_VALID;
}
#ifdef notdef
/* why ??? */
if (fs->fs_flags & FSF_WANT)
wakeup_srvr(fs);
#endif /* notdef */
map_flush_srvr(fs);
} else {
if (fs->fs_flags & FSF_VALID) {
#ifdef DEBUG
dlog("file server %s type nfs is still up", fs->fs_host);
#endif /* DEBUG */
} else {
if (np->np_ping > 1)
srvrlog(fs, "ok");
fs->fs_flags |= FSF_VALID;
}
}
/*
* Adjust ping interval
*/
untimeout(fs->fs_cid);
fs->fs_cid = timeout(fs->fs_pinger, nfs_keepalive, (voidp) fs);
/*
* Update ttl for this server
*/
np->np_ttl = clocktime() +
(MAX_ALLOWED_PINGS - 1) * FAST_NFS_PING + fs->fs_pinger - 1;
/*
* New RPC xid...
*/
np->np_xid = NPXID_ALLOC();
/*
* Failed pings is zero...
*/
np->np_ping = 0;
/*
* Recompute portmap information if not known
*/
if (np->np_mountd_inval)
recompute_portmap(fs);
#ifdef DEBUG
found_map++;
#endif /* DEBUG */
break;
}
}
#ifdef DEBUG
if (found_map == 0)
dlog("Spurious ping packet");
#endif /* DEBUG */
}
/*
* Called when no ping-reply received
*/
static void nfs_timed_out P((fserver *fs));
static void nfs_timed_out(fs)
fserver *fs;
{
nfs_private *np = (nfs_private *) fs->fs_private;
/*
* Another ping has failed
*/
np->np_ping++;
/*
* Not known to be up any longer
*/
if (FSRV_ISUP(fs)) {
fs->fs_flags &= ~FSF_VALID;
if (np->np_ping > 1)
srvrlog(fs, "not responding");
}
/*
* If ttl has expired then guess that it is dead
*/
if (np->np_ttl < clocktime()) {
int oflags = fs->fs_flags;
if ((fs->fs_flags & FSF_DOWN) == 0) {
/*
* Server was up, but is now down.
*/
srvrlog(fs, "is down");
fs->fs_flags |= FSF_DOWN|FSF_VALID;
/*
* Since the server is down, the portmap
* information may now be wrong, so it
* must be flushed from the local cache
*/
flush_nfs_fhandle_cache(fs);
np->np_error = -1;
#ifdef notdef
/*
* Pretend just one ping has failed now
*/
np->np_ping = 1;
#endif
} else {
/*
* Known to be down
*/
#ifdef DEBUG
if ((fs->fs_flags & FSF_VALID) == 0)
srvrlog(fs, "starts down");
#endif
fs->fs_flags |= FSF_VALID;
}
if (oflags != fs->fs_flags && (fs->fs_flags & FSF_WANT))
wakeup_srvr(fs);
} else {
#ifdef DEBUG
if (np->np_ping > 1)
dlog("%d pings to %s failed - at most %d allowed", np->np_ping, fs->fs_host, MAX_ALLOWED_PINGS);
#endif /* DEBUG */
}
/*
* Run keepalive again
*/
nfs_keepalive(fs);
}
/*
* Keep track of whether a server is alive
*/
static void nfs_keepalive P((fserver *fs));
static void nfs_keepalive(fs)
fserver *fs;
{
int error;
nfs_private *np = (nfs_private *) fs->fs_private;
int fstimeo = -1;
/*
* Send an NFS ping to this node
*/
if (ping_len == 0)
start_ping();
/*
* Queue the packet...
*/
error = fwd_packet(MK_RPC_XID(RPC_XID_NFSPING, np->np_xid), (voidp) ping_buf,
ping_len, fs->fs_ip, (struct sockaddr_in *) 0, (voidp) np->np_xid, nfs_pinged);
/*
* See if a hard error occured
*/
switch (error) {
case ENETDOWN:
case ENETUNREACH:
case EHOSTDOWN:
case EHOSTUNREACH:
np->np_ping = MAX_ALLOWED_PINGS; /* immediately down */
np->np_ttl = (time_t) 0;
/*
* This causes an immediate call to nfs_timed_out
* whenever the server was thought to be up.
* See +++ below.
*/
fstimeo = 0;
break;
case 0:
#ifdef DEBUG
dlog("Sent NFS ping to %s", fs->fs_host);
#endif /* DEBUG */
break;
}
#ifdef DEBUG
/*dlog("keepalive, ping = %d", np->np_ping);*/
#endif /* DEBUG */
/*
* Back off the ping interval if we are not getting replies and
* the remote system is know to be down.
*/
switch (fs->fs_flags & (FSF_DOWN|FSF_VALID)) {
case FSF_VALID: /* Up */
if (fstimeo < 0) /* +++ see above */
fstimeo = FAST_NFS_PING;
break;
case FSF_VALID|FSF_DOWN: /* Down */
fstimeo = fs->fs_pinger;
break;
default: /* Unknown */
fstimeo = FAST_NFS_PING;
break;
}
#ifdef DEBUG
dlog("NFS timeout in %d seconds", fstimeo);
#endif /* DEBUG */
fs->fs_cid = timeout(fstimeo, nfs_timed_out, (voidp) fs);
}
int nfs_srvr_port P((fserver *fs, u_short *port, voidp wchan));
int nfs_srvr_port(fs, port, wchan)
fserver *fs;
u_short *port;
voidp wchan;
{
int error = -1;
if ((fs->fs_flags & FSF_VALID) == FSF_VALID) {
if ((fs->fs_flags & FSF_DOWN) == 0) {
nfs_private *np = (nfs_private *) fs->fs_private;
if (np->np_error == 0) {
*port = np->np_mountd;
error = 0;
} else {
error = np->np_error;
}
/*
* Now go get the port mapping again in case it changed.
* Note that it is used even if (np_mountd_inval)
* is True. The flag is used simply as an
* indication that the mountd may be invalid, not
* that it is known to be invalid.
*/
if (np->np_mountd_inval)
recompute_portmap(fs);
else
np->np_mountd_inval = TRUE;
} else {
error = EWOULDBLOCK;
}
}
if (error < 0 && wchan && !(fs->fs_flags & FSF_WANT)) {
/*
* If a wait channel is supplied, and no
* error has yet occured, then arrange
* that a wakeup is done on the wait channel,
* whenever a wakeup is done on this fs node.
* Wakeup's are done on the fs node whenever
* it changes state - thus causing control to
* come back here and new, better things to happen.
*/
fs->fs_flags |= FSF_WANT;
sched_task(wakeup_task, wchan, (voidp) fs);
}
return error;
}
static void start_nfs_pings P((fserver *fs, int pingval));
static void start_nfs_pings(fs, pingval)
fserver *fs;
int pingval;
{
if (!(fs->fs_flags & FSF_PINGING)) {
fs->fs_flags |= FSF_PINGING;
if (fs->fs_cid)
untimeout(fs->fs_cid);
if (pingval < 0) {
srvrlog(fs, "wired up");
fs->fs_flags |= FSF_VALID;
fs->fs_flags &= ~FSF_DOWN;
} else {
nfs_keepalive(fs);
}
} else {
#ifdef DEBUG
dlog("Already running pings to %s", fs->fs_host);
#endif /* DEBUG */
}
}
/*
* Find an nfs server for a host.
*/
fserver *find_nfs_srvr P((mntfs *mf));
fserver *find_nfs_srvr(mf)
mntfs *mf;
{
fserver *fs;
struct hostent *hp = 0;
char *host = mf->mf_fo->opt_rhost;
struct sockaddr_in *ip;
nfs_private *np;
int pingval;
/*
* Get ping interval from mount options.
* Current only used to decide whether pings
* are required or not. < 0 = no pings.
*/
{ struct mntent mnt;
mnt.mnt_opts = mf->mf_mopts;
pingval = hasmntval(&mnt, "ping");
#ifdef HAS_TCP_NFS
/*
* Over TCP mount, don't bother to do pings.
* This is experimental - maybe you want to
* do pings anyway...
*/
if (pingval == 0 && hasmntopt(&mnt, "tcp"))
pingval = -1;
#endif /* HAS_TCP_NFS */
}
/*
* lookup host address and canonical name
*/
hp = gethostbyname(host);
/*
* New code from Bob Harris <harris@basil-rathbone.mit.edu>
* Use canonical name to keep track of file server
* information. This way aliases do not generate
* multiple NFS pingers. (Except when we're normalizing
* hosts.)
*/
if (hp && !normalize_hosts) host = hp->h_name;
ITER(fs, fserver, &nfs_srvr_list) {
if (STREQ(host, fs->fs_host)) {
start_nfs_pings(fs, pingval);
fs->fs_refc++;
return fs;
}
}
/*
* Get here if we can't find an entry
*/
if (hp) {
switch (hp->h_addrtype) {
case AF_INET:
ip = ALLOC(sockaddr_in);
bzero((voidp) ip, sizeof(*ip));
ip->sin_family = AF_INET;
bcopy((voidp) hp->h_addr, (voidp) &ip->sin_addr, sizeof(ip->sin_addr));
ip->sin_port = htons(NFS_PORT);
break;
default:
ip = 0;
break;
}
} else {
plog(XLOG_USER, "Unknown host: %s", host);
ip = 0;
}
/*
* Allocate a new server
*/
fs = ALLOC(fserver);
fs->fs_refc = 1;
fs->fs_host = strdup(hp ? hp->h_name : "unknown_hostname");
if (normalize_hosts) host_normalize(&fs->fs_host);
fs->fs_ip = ip;
fs->fs_cid = 0;
if (ip) {
fs->fs_flags = FSF_DOWN; /* Starts off down */
} else {
fs->fs_flags = FSF_ERROR|FSF_VALID;
mf->mf_flags |= MFF_ERROR;
mf->mf_error = ENOENT;
}
fs->fs_type = "nfs";
fs->fs_pinger = AM_PINGER;
np = ALLOC(nfs_private);
bzero((voidp) np, sizeof(*np));
np->np_mountd_inval = TRUE;
np->np_xid = NPXID_ALLOC();
np->np_error = -1;
/*
* Initially the server will be deemed dead after
* MAX_ALLOWED_PINGS of the fast variety have failed.
*/
np->np_ttl = clocktime() + MAX_ALLOWED_PINGS * FAST_NFS_PING - 1;
fs->fs_private = (voidp) np;
fs->fs_prfree = (void (*)()) free;
if (!(fs->fs_flags & FSF_ERROR)) {
/*
* Start of keepalive timer
*/
start_nfs_pings(fs, pingval);
}
/*
* Add to list of servers
*/
ins_que(&fs->fs_q, &nfs_srvr_list);
return fs;
}