freebsd-skq/sys/rpc/clnt_rc.c
rmacklem 6e30b78167 For the case where another thread was doing a connect and that
connect failed, the thread would be left stuck in msleep()
indefinitely, since it would call msleep() again for the case
where rc_client == NULL. Change the loop criteria and the if just
after the loop, so that this case is handled correctly.

Reviewed by:	dfr
Approved by:	kib (mentor)
2009-06-10 19:02:09 +00:00

479 lines
11 KiB
C

/*-
* Copyright (c) 2008 Isilon Inc http://www.isilon.com/
* Authors: Doug Rabson <dfr@rabson.org>
* Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <rpc/rpc.h>
#include <rpc/rpc_com.h>
static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
static void clnt_reconnect_abort(CLIENT *);
static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
static void clnt_reconnect_close(CLIENT *);
static void clnt_reconnect_destroy(CLIENT *);
static struct clnt_ops clnt_reconnect_ops = {
.cl_call = clnt_reconnect_call,
.cl_abort = clnt_reconnect_abort,
.cl_geterr = clnt_reconnect_geterr,
.cl_freeres = clnt_reconnect_freeres,
.cl_close = clnt_reconnect_close,
.cl_destroy = clnt_reconnect_destroy,
.cl_control = clnt_reconnect_control
};
static int fake_wchan;
struct rc_data {
struct mtx rc_lock;
struct sockaddr_storage rc_addr; /* server address */
struct netconfig* rc_nconf; /* network type */
rpcprog_t rc_prog; /* program number */
rpcvers_t rc_vers; /* version number */
size_t rc_sendsz;
size_t rc_recvsz;
struct timeval rc_timeout;
struct timeval rc_retry;
int rc_retries;
int rc_privport;
char *rc_waitchan;
int rc_intr;
int rc_connecting;
int rc_closed;
struct ucred *rc_ucred;
CLIENT* rc_client; /* underlying RPC client */
struct rpc_err rc_err;
};
CLIENT *
clnt_reconnect_create(
struct netconfig *nconf, /* network type */
struct sockaddr *svcaddr, /* servers address */
rpcprog_t program, /* program number */
rpcvers_t version, /* version number */
size_t sendsz, /* buffer recv size */
size_t recvsz) /* buffer send size */
{
CLIENT *cl = NULL; /* client handle */
struct rc_data *rc = NULL; /* private data */
if (svcaddr == NULL) {
rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
return (NULL);
}
cl = mem_alloc(sizeof (CLIENT));
rc = mem_alloc(sizeof (*rc));
mtx_init(&rc->rc_lock, "rc->rc_lock", NULL, MTX_DEF);
(void) memcpy(&rc->rc_addr, svcaddr, (size_t)svcaddr->sa_len);
rc->rc_nconf = nconf;
rc->rc_prog = program;
rc->rc_vers = version;
rc->rc_sendsz = sendsz;
rc->rc_recvsz = recvsz;
rc->rc_timeout.tv_sec = -1;
rc->rc_timeout.tv_usec = -1;
rc->rc_retry.tv_sec = 3;
rc->rc_retry.tv_usec = 0;
rc->rc_retries = INT_MAX;
rc->rc_privport = FALSE;
rc->rc_waitchan = "rpcrecv";
rc->rc_intr = 0;
rc->rc_connecting = FALSE;
rc->rc_closed = FALSE;
rc->rc_ucred = crdup(curthread->td_ucred);
rc->rc_client = NULL;
cl->cl_refs = 1;
cl->cl_ops = &clnt_reconnect_ops;
cl->cl_private = (caddr_t)(void *)rc;
cl->cl_auth = authnone_create();
cl->cl_tp = NULL;
cl->cl_netid = NULL;
return (cl);
}
static enum clnt_stat
clnt_reconnect_connect(CLIENT *cl)
{
struct thread *td = curthread;
struct rc_data *rc = (struct rc_data *)cl->cl_private;
struct socket *so;
enum clnt_stat stat;
int error;
int one = 1;
struct ucred *oldcred;
mtx_lock(&rc->rc_lock);
again:
if (rc->rc_closed) {
mtx_unlock(&rc->rc_lock);
return (RPC_CANTSEND);
}
if (rc->rc_connecting) {
while (!rc->rc_closed && !rc->rc_client && rc->rc_connecting) {
error = msleep(rc, &rc->rc_lock,
rc->rc_intr ? PCATCH : 0, "rpcrecon", 0);
if (error) {
mtx_unlock(&rc->rc_lock);
return (RPC_INTR);
}
}
/*
* If the other guy failed to connect, we might as
* well have another go.
*/
if (!rc->rc_client || rc->rc_closed)
goto again;
mtx_unlock(&rc->rc_lock);
return (RPC_SUCCESS);
} else {
rc->rc_connecting = TRUE;
}
mtx_unlock(&rc->rc_lock);
so = __rpc_nconf2socket(rc->rc_nconf);
if (!so) {
stat = rpc_createerr.cf_stat = RPC_TLIERROR;
rpc_createerr.cf_error.re_errno = 0;
goto out;
}
oldcred = td->td_ucred;
td->td_ucred = rc->rc_ucred;
if (rc->rc_privport)
bindresvport(so, NULL);
if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS)
rc->rc_client = clnt_dg_create(so,
(struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
rc->rc_sendsz, rc->rc_recvsz);
else
rc->rc_client = clnt_vc_create(so,
(struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
rc->rc_sendsz, rc->rc_recvsz);
td->td_ucred = oldcred;
if (!rc->rc_client) {
soclose(so);
rc->rc_err = rpc_createerr.cf_error;
stat = rpc_createerr.cf_stat;
goto out;
}
CLNT_CONTROL(rc->rc_client, CLSET_FD_CLOSE, 0);
CLNT_CONTROL(rc->rc_client, CLSET_CONNECT, &one);
CLNT_CONTROL(rc->rc_client, CLSET_TIMEOUT, &rc->rc_timeout);
CLNT_CONTROL(rc->rc_client, CLSET_RETRY_TIMEOUT, &rc->rc_retry);
CLNT_CONTROL(rc->rc_client, CLSET_WAITCHAN, rc->rc_waitchan);
CLNT_CONTROL(rc->rc_client, CLSET_INTERRUPTIBLE, &rc->rc_intr);
stat = RPC_SUCCESS;
out:
mtx_lock(&rc->rc_lock);
if (rc->rc_closed) {
if (rc->rc_client) {
CLNT_CLOSE(rc->rc_client);
CLNT_RELEASE(rc->rc_client);
rc->rc_client = NULL;
}
}
rc->rc_connecting = FALSE;
wakeup(rc);
mtx_unlock(&rc->rc_lock);
return (stat);
}
static enum clnt_stat
clnt_reconnect_call(
CLIENT *cl, /* client handle */
struct rpc_callextra *ext, /* call metadata */
rpcproc_t proc, /* procedure number */
struct mbuf *args, /* pointer to args */
struct mbuf **resultsp, /* pointer to results */
struct timeval utimeout)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
CLIENT *client;
enum clnt_stat stat;
int tries;
tries = 0;
do {
if (rc->rc_closed) {
return (RPC_CANTSEND);
}
if (!rc->rc_client) {
stat = clnt_reconnect_connect(cl);
if (stat == RPC_SYSTEMERROR) {
(void) tsleep(&fake_wchan, 0,
"rpccon", hz);
tries++;
if (tries >= rc->rc_retries)
return (stat);
continue;
}
if (stat != RPC_SUCCESS)
return (stat);
}
mtx_lock(&rc->rc_lock);
if (!rc->rc_client) {
mtx_unlock(&rc->rc_lock);
stat = RPC_FAILED;
continue;
}
CLNT_ACQUIRE(rc->rc_client);
client = rc->rc_client;
mtx_unlock(&rc->rc_lock);
stat = CLNT_CALL_MBUF(client, ext, proc, args,
resultsp, utimeout);
if (stat != RPC_SUCCESS) {
if (!ext)
CLNT_GETERR(client, &rc->rc_err);
}
CLNT_RELEASE(client);
if (stat == RPC_TIMEDOUT) {
/*
* Check for async send misfeature for NLM
* protocol.
*/
if ((rc->rc_timeout.tv_sec == 0
&& rc->rc_timeout.tv_usec == 0)
|| (rc->rc_timeout.tv_sec == -1
&& utimeout.tv_sec == 0
&& utimeout.tv_usec == 0)) {
break;
}
}
if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND
|| stat == RPC_CANTRECV) {
tries++;
if (tries >= rc->rc_retries)
break;
if (ext && ext->rc_feedback)
ext->rc_feedback(FEEDBACK_RECONNECT, proc,
ext->rc_feedback_arg);
mtx_lock(&rc->rc_lock);
/*
* Make sure that someone else hasn't already
* reconnected.
*/
if (rc->rc_client == client) {
CLNT_RELEASE(rc->rc_client);
rc->rc_client = NULL;
}
mtx_unlock(&rc->rc_lock);
} else {
break;
}
} while (stat != RPC_SUCCESS);
KASSERT(stat != RPC_SUCCESS || *resultsp,
("RPC_SUCCESS without reply"));
return (stat);
}
static void
clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
*errp = rc->rc_err;
}
static bool_t
clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr));
}
/*ARGSUSED*/
static void
clnt_reconnect_abort(CLIENT *h)
{
}
static bool_t
clnt_reconnect_control(CLIENT *cl, u_int request, void *info)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
if (info == NULL) {
return (FALSE);
}
switch (request) {
case CLSET_TIMEOUT:
rc->rc_timeout = *(struct timeval *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_TIMEOUT:
*(struct timeval *)info = rc->rc_timeout;
break;
case CLSET_RETRY_TIMEOUT:
rc->rc_retry = *(struct timeval *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_RETRY_TIMEOUT:
*(struct timeval *)info = rc->rc_retry;
break;
case CLGET_VERS:
*(uint32_t *)info = rc->rc_vers;
break;
case CLSET_VERS:
rc->rc_vers = *(uint32_t *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, CLSET_VERS, info);
break;
case CLGET_PROG:
*(uint32_t *)info = rc->rc_prog;
break;
case CLSET_PROG:
rc->rc_prog = *(uint32_t *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLSET_WAITCHAN:
rc->rc_waitchan = (char *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_WAITCHAN:
*(const char **) info = rc->rc_waitchan;
break;
case CLSET_INTERRUPTIBLE:
rc->rc_intr = *(int *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_INTERRUPTIBLE:
*(int *) info = rc->rc_intr;
break;
case CLSET_RETRIES:
rc->rc_retries = *(int *) info;
break;
case CLGET_RETRIES:
*(int *) info = rc->rc_retries;
break;
case CLSET_PRIVPORT:
rc->rc_privport = *(int *) info;
break;
case CLGET_PRIVPORT:
*(int *) info = rc->rc_privport;
break;
default:
return (FALSE);
}
return (TRUE);
}
static void
clnt_reconnect_close(CLIENT *cl)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
CLIENT *client;
mtx_lock(&rc->rc_lock);
if (rc->rc_closed) {
mtx_unlock(&rc->rc_lock);
return;
}
rc->rc_closed = TRUE;
client = rc->rc_client;
rc->rc_client = NULL;
mtx_unlock(&rc->rc_lock);
if (client) {
CLNT_CLOSE(client);
CLNT_RELEASE(client);
}
}
static void
clnt_reconnect_destroy(CLIENT *cl)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
if (rc->rc_client)
CLNT_DESTROY(rc->rc_client);
crfree(rc->rc_ucred);
mtx_destroy(&rc->rc_lock);
mem_free(rc, sizeof(*rc));
mem_free(cl, sizeof (CLIENT));
}