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freebsd-skq/sys/rpc/clnt_vc.c
rmacklem c273faa6c6 Fix the client side krpc from doing TCP reconnects for ERESTART from sosend(). 
When sosend() replies ERESTART in the client side krpc, it indicates that
the RPC message hasn't yet been sent and that the send queue is full or
locked while a signal is posted for the process.
Without this patch, this would result in a RPC_CANTSEND reply from
clnt_vc_call(), which would cause clnt_reconnect_call() to create a new
TCP transport connection. For most NFS servers, this wasn't a serious problem,
although it did imply retries of outstanding RPCs, which could possibly
have missed the DRC.
For an NFSv4.1 mount to AmazonEFS, this caused a serious problem, since
AmazonEFS often didn't retain the NFSv4.1 session and would reply with
NFS4ERR_BAD_SESSION. This implies to the client a crash/reboot which
requires open/lock state recovery.

Three options were considered to fix this:
- Return the ERESTART all the way up to the system call boundary and then
  have the system call redone. This is fraught with risk, due to convoluted
  code paths, asynchronous I/O RPCs etc. cperciva@ worked on this, but it
  is still a work in prgress and may not be feasible.
- Set SB_NOINTR for the socket buffer. This fixes the problem, but makes
  the sosend() completely non interruptible, which kib@ considered
  inappropriate. It also would break forced dismount when a thread
  was blocked in sosend().
- Modify the retry loop in clnt_vc_call(), so that it loops for this case
  for up to 15sec. Testing showed that the sosend() usually succeeded by
  the 2nd retry. The extreme case observed was 111 loop iterations, or
  about 100msec of delay.
This third alternative is what is implemented in this patch, since the
change is:
- localized
- straightforward
- forced dismount is not broken by it.

This patch has been tested by cperciva@ extensively against AmazonEFS.

Reported by:	cperciva
Tested by:	cperciva
MFC after:	2 weeks
2017-05-07 12:12:45 +00:00

1080 lines
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/* $NetBSD: clnt_vc.c,v 1.4 2000/07/14 08:40:42 fvdl Exp $ */
/*-
* Copyright (c) 2009, Sun Microsystems, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - 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.
* - Neither the name of Sun Microsystems, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *sccsid2 = "@(#)clnt_tcp.c 1.37 87/10/05 Copyr 1984 Sun Micro";
static char *sccsid = "@(#)clnt_tcp.c 2.2 88/08/01 4.0 RPCSRC";
static char sccsid3[] = "@(#)clnt_vc.c 1.19 89/03/16 Copyr 1988 Sun Micro";
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* clnt_tcp.c, Implements a TCP/IP based, client side RPC.
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*
* TCP based RPC supports 'batched calls'.
* A sequence of calls may be batched-up in a send buffer. The rpc call
* return immediately to the client even though the call was not necessarily
* sent. The batching occurs if the results' xdr routine is NULL (0) AND
* the rpc timeout value is zero (see clnt.h, rpc).
*
* Clients should NOT casually batch calls that in fact return results; that is,
* the server side should be aware that a call is batched and not produce any
* return message. Batched calls that produce many result messages can
* deadlock (netlock) the client and the server....
*
* Now go hang yourself.
*/
#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/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/syslog.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <net/vnet.h>
#include <netinet/tcp.h>
#include <rpc/rpc.h>
#include <rpc/rpc_com.h>
#include <rpc/krpc.h>
struct cmessage {
struct cmsghdr cmsg;
struct cmsgcred cmcred;
};
static enum clnt_stat clnt_vc_call(CLIENT *, struct rpc_callextra *,
rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
static void clnt_vc_geterr(CLIENT *, struct rpc_err *);
static bool_t clnt_vc_freeres(CLIENT *, xdrproc_t, void *);
static void clnt_vc_abort(CLIENT *);
static bool_t clnt_vc_control(CLIENT *, u_int, void *);
static void clnt_vc_close(CLIENT *);
static void clnt_vc_destroy(CLIENT *);
static bool_t time_not_ok(struct timeval *);
static int clnt_vc_soupcall(struct socket *so, void *arg, int waitflag);
static struct clnt_ops clnt_vc_ops = {
.cl_call = clnt_vc_call,
.cl_abort = clnt_vc_abort,
.cl_geterr = clnt_vc_geterr,
.cl_freeres = clnt_vc_freeres,
.cl_close = clnt_vc_close,
.cl_destroy = clnt_vc_destroy,
.cl_control = clnt_vc_control
};
static void clnt_vc_upcallsdone(struct ct_data *);
static int fake_wchan;
/*
* Create a client handle for a connection.
* Default options are set, which the user can change using clnt_control()'s.
* The rpc/vc package does buffering similar to stdio, so the client
* must pick send and receive buffer sizes, 0 => use the default.
* NB: fd is copied into a private area.
* NB: The rpch->cl_auth is set null authentication. Caller may wish to
* set this something more useful.
*
* fd should be an open socket
*/
CLIENT *
clnt_vc_create(
struct socket *so, /* open file descriptor */
struct sockaddr *raddr, /* servers address */
const rpcprog_t prog, /* program number */
const rpcvers_t vers, /* version number */
size_t sendsz, /* buffer recv size */
size_t recvsz, /* buffer send size */
int intrflag) /* interruptible */
{
CLIENT *cl; /* client handle */
struct ct_data *ct = NULL; /* client handle */
struct timeval now;
struct rpc_msg call_msg;
static uint32_t disrupt;
struct __rpc_sockinfo si;
XDR xdrs;
int error, interrupted, one = 1, sleep_flag;
struct sockopt sopt;
if (disrupt == 0)
disrupt = (uint32_t)(long)raddr;
cl = (CLIENT *)mem_alloc(sizeof (*cl));
ct = (struct ct_data *)mem_alloc(sizeof (*ct));
mtx_init(&ct->ct_lock, "ct->ct_lock", NULL, MTX_DEF);
ct->ct_threads = 0;
ct->ct_closing = FALSE;
ct->ct_closed = FALSE;
ct->ct_upcallrefs = 0;
if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
error = soconnect(so, raddr, curthread);
SOCK_LOCK(so);
interrupted = 0;
sleep_flag = PSOCK;
if (intrflag != 0)
sleep_flag |= PCATCH;
while ((so->so_state & SS_ISCONNECTING)
&& so->so_error == 0) {
error = msleep(&so->so_timeo, SOCK_MTX(so),
sleep_flag, "connec", 0);
if (error) {
if (error == EINTR || error == ERESTART)
interrupted = 1;
break;
}
}
if (error == 0) {
error = so->so_error;
so->so_error = 0;
}
SOCK_UNLOCK(so);
if (error) {
if (!interrupted)
so->so_state &= ~SS_ISCONNECTING;
rpc_createerr.cf_stat = RPC_SYSTEMERROR;
rpc_createerr.cf_error.re_errno = error;
goto err;
}
}
if (!__rpc_socket2sockinfo(so, &si)) {
goto err;
}
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
bzero(&sopt, sizeof(sopt));
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = SOL_SOCKET;
sopt.sopt_name = SO_KEEPALIVE;
sopt.sopt_val = &one;
sopt.sopt_valsize = sizeof(one);
sosetopt(so, &sopt);
}
if (so->so_proto->pr_protocol == IPPROTO_TCP) {
bzero(&sopt, sizeof(sopt));
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = IPPROTO_TCP;
sopt.sopt_name = TCP_NODELAY;
sopt.sopt_val = &one;
sopt.sopt_valsize = sizeof(one);
sosetopt(so, &sopt);
}
ct->ct_closeit = FALSE;
/*
* Set up private data struct
*/
ct->ct_socket = so;
ct->ct_wait.tv_sec = -1;
ct->ct_wait.tv_usec = -1;
memcpy(&ct->ct_addr, raddr, raddr->sa_len);
/*
* Initialize call message
*/
getmicrotime(&now);
ct->ct_xid = ((uint32_t)++disrupt) ^ __RPC_GETXID(&now);
call_msg.rm_xid = ct->ct_xid;
call_msg.rm_direction = CALL;
call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
call_msg.rm_call.cb_prog = (uint32_t)prog;
call_msg.rm_call.cb_vers = (uint32_t)vers;
/*
* pre-serialize the static part of the call msg and stash it away
*/
xdrmem_create(&xdrs, ct->ct_mcallc, MCALL_MSG_SIZE,
XDR_ENCODE);
if (! xdr_callhdr(&xdrs, &call_msg)) {
if (ct->ct_closeit) {
soclose(ct->ct_socket);
}
goto err;
}
ct->ct_mpos = XDR_GETPOS(&xdrs);
XDR_DESTROY(&xdrs);
ct->ct_waitchan = "rpcrecv";
ct->ct_waitflag = 0;
/*
* Create a client handle which uses xdrrec for serialization
* and authnone for authentication.
*/
sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
error = soreserve(ct->ct_socket, sendsz, recvsz);
if (error != 0) {
if (ct->ct_closeit) {
soclose(ct->ct_socket);
}
goto err;
}
cl->cl_refs = 1;
cl->cl_ops = &clnt_vc_ops;
cl->cl_private = ct;
cl->cl_auth = authnone_create();
SOCKBUF_LOCK(&ct->ct_socket->so_rcv);
soupcall_set(ct->ct_socket, SO_RCV, clnt_vc_soupcall, ct);
SOCKBUF_UNLOCK(&ct->ct_socket->so_rcv);
ct->ct_record = NULL;
ct->ct_record_resid = 0;
TAILQ_INIT(&ct->ct_pending);
return (cl);
err:
mtx_destroy(&ct->ct_lock);
mem_free(ct, sizeof (struct ct_data));
mem_free(cl, sizeof (CLIENT));
return ((CLIENT *)NULL);
}
static enum clnt_stat
clnt_vc_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 ct_data *ct = (struct ct_data *) cl->cl_private;
AUTH *auth;
struct rpc_err *errp;
enum clnt_stat stat;
XDR xdrs;
struct rpc_msg reply_msg;
bool_t ok;
int nrefreshes = 2; /* number of times to refresh cred */
struct timeval timeout;
uint32_t xid;
struct mbuf *mreq = NULL, *results;
struct ct_request *cr;
int error, trycnt;
cr = malloc(sizeof(struct ct_request), M_RPC, M_WAITOK);
mtx_lock(&ct->ct_lock);
if (ct->ct_closing || ct->ct_closed) {
mtx_unlock(&ct->ct_lock);
free(cr, M_RPC);
return (RPC_CANTSEND);
}
ct->ct_threads++;
if (ext) {
auth = ext->rc_auth;
errp = &ext->rc_err;
} else {
auth = cl->cl_auth;
errp = &ct->ct_error;
}
cr->cr_mrep = NULL;
cr->cr_error = 0;
if (ct->ct_wait.tv_usec == -1) {
timeout = utimeout; /* use supplied timeout */
} else {
timeout = ct->ct_wait; /* use default timeout */
}
/*
* After 15sec of looping, allow it to return RPC_CANTSEND, which will
* cause the clnt_reconnect layer to create a new TCP connection.
*/
trycnt = 15 * hz;
call_again:
mtx_assert(&ct->ct_lock, MA_OWNED);
if (ct->ct_closing || ct->ct_closed) {
ct->ct_threads--;
wakeup(ct);
mtx_unlock(&ct->ct_lock);
free(cr, M_RPC);
return (RPC_CANTSEND);
}
ct->ct_xid++;
xid = ct->ct_xid;
mtx_unlock(&ct->ct_lock);
/*
* Leave space to pre-pend the record mark.
*/
mreq = m_gethdr(M_WAITOK, MT_DATA);
mreq->m_data += sizeof(uint32_t);
KASSERT(ct->ct_mpos + sizeof(uint32_t) <= MHLEN,
("RPC header too big"));
bcopy(ct->ct_mcallc, mreq->m_data, ct->ct_mpos);
mreq->m_len = ct->ct_mpos;
/*
* The XID is the first thing in the request.
*/
*mtod(mreq, uint32_t *) = htonl(xid);
xdrmbuf_create(&xdrs, mreq, XDR_ENCODE);
errp->re_status = stat = RPC_SUCCESS;
if ((! XDR_PUTINT32(&xdrs, &proc)) ||
(! AUTH_MARSHALL(auth, xid, &xdrs,
m_copym(args, 0, M_COPYALL, M_WAITOK)))) {
errp->re_status = stat = RPC_CANTENCODEARGS;
mtx_lock(&ct->ct_lock);
goto out;
}
mreq->m_pkthdr.len = m_length(mreq, NULL);
/*
* Prepend a record marker containing the packet length.
*/
M_PREPEND(mreq, sizeof(uint32_t), M_WAITOK);
*mtod(mreq, uint32_t *) =
htonl(0x80000000 | (mreq->m_pkthdr.len - sizeof(uint32_t)));
cr->cr_xid = xid;
mtx_lock(&ct->ct_lock);
/*
* Check to see if the other end has already started to close down
* the connection. The upcall will have set ct_error.re_status
* to RPC_CANTRECV if this is the case.
* If the other end starts to close down the connection after this
* point, it will be detected later when cr_error is checked,
* since the request is in the ct_pending queue.
*/
if (ct->ct_error.re_status == RPC_CANTRECV) {
if (errp != &ct->ct_error) {
errp->re_errno = ct->ct_error.re_errno;
errp->re_status = RPC_CANTRECV;
}
stat = RPC_CANTRECV;
goto out;
}
TAILQ_INSERT_TAIL(&ct->ct_pending, cr, cr_link);
mtx_unlock(&ct->ct_lock);
/*
* sosend consumes mreq.
*/
error = sosend(ct->ct_socket, NULL, NULL, mreq, NULL, 0, curthread);
mreq = NULL;
if (error == EMSGSIZE || (error == ERESTART &&
(ct->ct_waitflag & PCATCH) == 0 && trycnt-- > 0)) {
SOCKBUF_LOCK(&ct->ct_socket->so_snd);
sbwait(&ct->ct_socket->so_snd);
SOCKBUF_UNLOCK(&ct->ct_socket->so_snd);
AUTH_VALIDATE(auth, xid, NULL, NULL);
mtx_lock(&ct->ct_lock);
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
/* Sleep for 1 clock tick before trying the sosend() again. */
msleep(&fake_wchan, &ct->ct_lock, 0, "rpclpsnd", 1);
goto call_again;
}
reply_msg.acpted_rply.ar_verf.oa_flavor = AUTH_NULL;
reply_msg.acpted_rply.ar_verf.oa_base = cr->cr_verf;
reply_msg.acpted_rply.ar_verf.oa_length = 0;
reply_msg.acpted_rply.ar_results.where = NULL;
reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
mtx_lock(&ct->ct_lock);
if (error) {
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
errp->re_errno = error;
errp->re_status = stat = RPC_CANTSEND;
goto out;
}
/*
* Check to see if we got an upcall while waiting for the
* lock. In both these cases, the request has been removed
* from ct->ct_pending.
*/
if (cr->cr_error) {
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
errp->re_errno = cr->cr_error;
errp->re_status = stat = RPC_CANTRECV;
goto out;
}
if (cr->cr_mrep) {
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
goto got_reply;
}
/*
* Hack to provide rpc-based message passing
*/
if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
errp->re_status = stat = RPC_TIMEDOUT;
goto out;
}
error = msleep(cr, &ct->ct_lock, ct->ct_waitflag, ct->ct_waitchan,
tvtohz(&timeout));
TAILQ_REMOVE(&ct->ct_pending, cr, cr_link);
if (error) {
/*
* The sleep returned an error so our request is still
* on the list. Turn the error code into an
* appropriate client status.
*/
errp->re_errno = error;
switch (error) {
case EINTR:
stat = RPC_INTR;
break;
case EWOULDBLOCK:
stat = RPC_TIMEDOUT;
break;
default:
stat = RPC_CANTRECV;
}
errp->re_status = stat;
goto out;
} else {
/*
* We were woken up by the upcall. If the
* upcall had a receive error, report that,
* otherwise we have a reply.
*/
if (cr->cr_error) {
errp->re_errno = cr->cr_error;
errp->re_status = stat = RPC_CANTRECV;
goto out;
}
}
got_reply:
/*
* Now decode and validate the response. We need to drop the
* lock since xdr_replymsg may end up sleeping in malloc.
*/
mtx_unlock(&ct->ct_lock);
if (ext && ext->rc_feedback)
ext->rc_feedback(FEEDBACK_OK, proc, ext->rc_feedback_arg);
xdrmbuf_create(&xdrs, cr->cr_mrep, XDR_DECODE);
ok = xdr_replymsg(&xdrs, &reply_msg);
cr->cr_mrep = NULL;
if (ok) {
if ((reply_msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
(reply_msg.acpted_rply.ar_stat == SUCCESS))
errp->re_status = stat = RPC_SUCCESS;
else
stat = _seterr_reply(&reply_msg, errp);
if (stat == RPC_SUCCESS) {
results = xdrmbuf_getall(&xdrs);
if (!AUTH_VALIDATE(auth, xid,
&reply_msg.acpted_rply.ar_verf,
&results)) {
errp->re_status = stat = RPC_AUTHERROR;
errp->re_why = AUTH_INVALIDRESP;
} else {
KASSERT(results,
("auth validated but no result"));
*resultsp = results;
}
} /* end successful completion */
/*
* If unsuccessful AND error is an authentication error
* then refresh credentials and try again, else break
*/
else if (stat == RPC_AUTHERROR)
/* maybe our credentials need to be refreshed ... */
if (nrefreshes > 0 &&
AUTH_REFRESH(auth, &reply_msg)) {
nrefreshes--;
XDR_DESTROY(&xdrs);
mtx_lock(&ct->ct_lock);
goto call_again;
}
/* end of unsuccessful completion */
} /* end of valid reply message */
else {
errp->re_status = stat = RPC_CANTDECODERES;
}
XDR_DESTROY(&xdrs);
mtx_lock(&ct->ct_lock);
out:
mtx_assert(&ct->ct_lock, MA_OWNED);
KASSERT(stat != RPC_SUCCESS || *resultsp,
("RPC_SUCCESS without reply"));
if (mreq)
m_freem(mreq);
if (cr->cr_mrep)
m_freem(cr->cr_mrep);
ct->ct_threads--;
if (ct->ct_closing)
wakeup(ct);
mtx_unlock(&ct->ct_lock);
if (auth && stat != RPC_SUCCESS)
AUTH_VALIDATE(auth, xid, NULL, NULL);
free(cr, M_RPC);
return (stat);
}
static void
clnt_vc_geterr(CLIENT *cl, struct rpc_err *errp)
{
struct ct_data *ct = (struct ct_data *) cl->cl_private;
*errp = ct->ct_error;
}
static bool_t
clnt_vc_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
{
XDR xdrs;
bool_t dummy;
xdrs.x_op = XDR_FREE;
dummy = (*xdr_res)(&xdrs, res_ptr);
return (dummy);
}
/*ARGSUSED*/
static void
clnt_vc_abort(CLIENT *cl)
{
}
static bool_t
clnt_vc_control(CLIENT *cl, u_int request, void *info)
{
struct ct_data *ct = (struct ct_data *)cl->cl_private;
void *infop = info;
SVCXPRT *xprt;
mtx_lock(&ct->ct_lock);
switch (request) {
case CLSET_FD_CLOSE:
ct->ct_closeit = TRUE;
mtx_unlock(&ct->ct_lock);
return (TRUE);
case CLSET_FD_NCLOSE:
ct->ct_closeit = FALSE;
mtx_unlock(&ct->ct_lock);
return (TRUE);
default:
break;
}
/* for other requests which use info */
if (info == NULL) {
mtx_unlock(&ct->ct_lock);
return (FALSE);
}
switch (request) {
case CLSET_TIMEOUT:
if (time_not_ok((struct timeval *)info)) {
mtx_unlock(&ct->ct_lock);
return (FALSE);
}
ct->ct_wait = *(struct timeval *)infop;
break;
case CLGET_TIMEOUT:
*(struct timeval *)infop = ct->ct_wait;
break;
case CLGET_SERVER_ADDR:
(void) memcpy(info, &ct->ct_addr, (size_t)ct->ct_addr.ss_len);
break;
case CLGET_SVC_ADDR:
/*
* Slightly different semantics to userland - we use
* sockaddr instead of netbuf.
*/
memcpy(info, &ct->ct_addr, ct->ct_addr.ss_len);
break;
case CLSET_SVC_ADDR: /* set to new address */
mtx_unlock(&ct->ct_lock);
return (FALSE);
case CLGET_XID:
*(uint32_t *)info = ct->ct_xid;
break;
case CLSET_XID:
/* This will set the xid of the NEXT call */
/* decrement by 1 as clnt_vc_call() increments once */
ct->ct_xid = *(uint32_t *)info - 1;
break;
case CLGET_VERS:
/*
* This RELIES on the information that, in the call body,
* the version number field is the fifth field from the
* beginning of the RPC header. MUST be changed if the
* call_struct is changed
*/
*(uint32_t *)info =
ntohl(*(uint32_t *)(void *)(ct->ct_mcallc +
4 * BYTES_PER_XDR_UNIT));
break;
case CLSET_VERS:
*(uint32_t *)(void *)(ct->ct_mcallc +
4 * BYTES_PER_XDR_UNIT) =
htonl(*(uint32_t *)info);
break;
case CLGET_PROG:
/*
* This RELIES on the information that, in the call body,
* the program number field is the fourth field from the
* beginning of the RPC header. MUST be changed if the
* call_struct is changed
*/
*(uint32_t *)info =
ntohl(*(uint32_t *)(void *)(ct->ct_mcallc +
3 * BYTES_PER_XDR_UNIT));
break;
case CLSET_PROG:
*(uint32_t *)(void *)(ct->ct_mcallc +
3 * BYTES_PER_XDR_UNIT) =
htonl(*(uint32_t *)info);
break;
case CLSET_WAITCHAN:
ct->ct_waitchan = (const char *)info;
break;
case CLGET_WAITCHAN:
*(const char **) info = ct->ct_waitchan;
break;
case CLSET_INTERRUPTIBLE:
if (*(int *) info)
ct->ct_waitflag = PCATCH;
else
ct->ct_waitflag = 0;
break;
case CLGET_INTERRUPTIBLE:
if (ct->ct_waitflag)
*(int *) info = TRUE;
else
*(int *) info = FALSE;
break;
case CLSET_BACKCHANNEL:
xprt = (SVCXPRT *)info;
if (ct->ct_backchannelxprt == NULL) {
xprt->xp_p2 = ct;
ct->ct_backchannelxprt = xprt;
}
break;
default:
mtx_unlock(&ct->ct_lock);
return (FALSE);
}
mtx_unlock(&ct->ct_lock);
return (TRUE);
}
static void
clnt_vc_close(CLIENT *cl)
{
struct ct_data *ct = (struct ct_data *) cl->cl_private;
struct ct_request *cr;
mtx_lock(&ct->ct_lock);
if (ct->ct_closed) {
mtx_unlock(&ct->ct_lock);
return;
}
if (ct->ct_closing) {
while (ct->ct_closing)
msleep(ct, &ct->ct_lock, 0, "rpcclose", 0);
KASSERT(ct->ct_closed, ("client should be closed"));
mtx_unlock(&ct->ct_lock);
return;
}
if (ct->ct_socket) {
ct->ct_closing = TRUE;
mtx_unlock(&ct->ct_lock);
SOCKBUF_LOCK(&ct->ct_socket->so_rcv);
soupcall_clear(ct->ct_socket, SO_RCV);
clnt_vc_upcallsdone(ct);
SOCKBUF_UNLOCK(&ct->ct_socket->so_rcv);
/*
* Abort any pending requests and wait until everyone
* has finished with clnt_vc_call.
*/
mtx_lock(&ct->ct_lock);
TAILQ_FOREACH(cr, &ct->ct_pending, cr_link) {
cr->cr_xid = 0;
cr->cr_error = ESHUTDOWN;
wakeup(cr);
}
while (ct->ct_threads)
msleep(ct, &ct->ct_lock, 0, "rpcclose", 0);
}
ct->ct_closing = FALSE;
ct->ct_closed = TRUE;
mtx_unlock(&ct->ct_lock);
wakeup(ct);
}
static void
clnt_vc_destroy(CLIENT *cl)
{
struct ct_data *ct = (struct ct_data *) cl->cl_private;
struct socket *so = NULL;
SVCXPRT *xprt;
clnt_vc_close(cl);
mtx_lock(&ct->ct_lock);
xprt = ct->ct_backchannelxprt;
ct->ct_backchannelxprt = NULL;
if (xprt != NULL) {
mtx_unlock(&ct->ct_lock); /* To avoid a LOR. */
sx_xlock(&xprt->xp_lock);
mtx_lock(&ct->ct_lock);
xprt->xp_p2 = NULL;
sx_xunlock(&xprt->xp_lock);
}
if (ct->ct_socket) {
if (ct->ct_closeit) {
so = ct->ct_socket;
}
}
mtx_unlock(&ct->ct_lock);
mtx_destroy(&ct->ct_lock);
if (so) {
soshutdown(so, SHUT_WR);
soclose(so);
}
mem_free(ct, sizeof(struct ct_data));
if (cl->cl_netid && cl->cl_netid[0])
mem_free(cl->cl_netid, strlen(cl->cl_netid) +1);
if (cl->cl_tp && cl->cl_tp[0])
mem_free(cl->cl_tp, strlen(cl->cl_tp) +1);
mem_free(cl, sizeof(CLIENT));
}
/*
* Make sure that the time is not garbage. -1 value is disallowed.
* Note this is different from time_not_ok in clnt_dg.c
*/
static bool_t
time_not_ok(struct timeval *t)
{
return (t->tv_sec <= -1 || t->tv_sec > 100000000 ||
t->tv_usec <= -1 || t->tv_usec > 1000000);
}
int
clnt_vc_soupcall(struct socket *so, void *arg, int waitflag)
{
struct ct_data *ct = (struct ct_data *) arg;
struct uio uio;
struct mbuf *m, *m2;
struct ct_request *cr;
int error, rcvflag, foundreq;
uint32_t xid_plus_direction[2], header;
bool_t do_read;
SVCXPRT *xprt;
struct cf_conn *cd;
CTASSERT(sizeof(xid_plus_direction) == 2 * sizeof(uint32_t));
ct->ct_upcallrefs++;
uio.uio_td = curthread;
do {
/*
* If ct_record_resid is zero, we are waiting for a
* record mark.
*/
if (ct->ct_record_resid == 0) {
/*
* Make sure there is either a whole record
* mark in the buffer or there is some other
* error condition
*/
do_read = FALSE;
if (sbavail(&so->so_rcv) >= sizeof(uint32_t)
|| (so->so_rcv.sb_state & SBS_CANTRCVMORE)
|| so->so_error)
do_read = TRUE;
if (!do_read)
break;
SOCKBUF_UNLOCK(&so->so_rcv);
uio.uio_resid = sizeof(uint32_t);
m = NULL;
rcvflag = MSG_DONTWAIT | MSG_SOCALLBCK;
error = soreceive(so, NULL, &uio, &m, NULL, &rcvflag);
SOCKBUF_LOCK(&so->so_rcv);
if (error == EWOULDBLOCK)
break;
/*
* If there was an error, wake up all pending
* requests.
*/
if (error || uio.uio_resid > 0) {
wakeup_all:
mtx_lock(&ct->ct_lock);
if (!error) {
/*
* We must have got EOF trying
* to read from the stream.
*/
error = ECONNRESET;
}
ct->ct_error.re_status = RPC_CANTRECV;
ct->ct_error.re_errno = error;
TAILQ_FOREACH(cr, &ct->ct_pending, cr_link) {
cr->cr_error = error;
wakeup(cr);
}
mtx_unlock(&ct->ct_lock);
break;
}
m_copydata(m, 0, sizeof(uint32_t), (char *)&header);
header = ntohl(header);
ct->ct_record = NULL;
ct->ct_record_resid = header & 0x7fffffff;
ct->ct_record_eor = ((header & 0x80000000) != 0);
m_freem(m);
} else {
/*
* Wait until the socket has the whole record
* buffered.
*/
do_read = FALSE;
if (sbavail(&so->so_rcv) >= ct->ct_record_resid
|| (so->so_rcv.sb_state & SBS_CANTRCVMORE)
|| so->so_error)
do_read = TRUE;
if (!do_read)
break;
/*
* We have the record mark. Read as much as
* the socket has buffered up to the end of
* this record.
*/
SOCKBUF_UNLOCK(&so->so_rcv);
uio.uio_resid = ct->ct_record_resid;
m = NULL;
rcvflag = MSG_DONTWAIT | MSG_SOCALLBCK;
error = soreceive(so, NULL, &uio, &m, NULL, &rcvflag);
SOCKBUF_LOCK(&so->so_rcv);
if (error == EWOULDBLOCK)
break;
if (error || uio.uio_resid == ct->ct_record_resid)
goto wakeup_all;
/*
* If we have part of the record already,
* chain this bit onto the end.
*/
if (ct->ct_record)
m_last(ct->ct_record)->m_next = m;
else
ct->ct_record = m;
ct->ct_record_resid = uio.uio_resid;
/*
* If we have the entire record, see if we can
* match it to a request.
*/
if (ct->ct_record_resid == 0
&& ct->ct_record_eor) {
/*
* The XID is in the first uint32_t of
* the reply and the message direction
* is the second one.
*/
if (ct->ct_record->m_len <
sizeof(xid_plus_direction) &&
m_length(ct->ct_record, NULL) <
sizeof(xid_plus_direction)) {
m_freem(ct->ct_record);
break;
}
m_copydata(ct->ct_record, 0,
sizeof(xid_plus_direction),
(char *)xid_plus_direction);
xid_plus_direction[0] =
ntohl(xid_plus_direction[0]);
xid_plus_direction[1] =
ntohl(xid_plus_direction[1]);
/* Check message direction. */
if (xid_plus_direction[1] == CALL) {
/* This is a backchannel request. */
mtx_lock(&ct->ct_lock);
xprt = ct->ct_backchannelxprt;
if (xprt == NULL) {
mtx_unlock(&ct->ct_lock);
/* Just throw it away. */
m_freem(ct->ct_record);
ct->ct_record = NULL;
} else {
cd = (struct cf_conn *)
xprt->xp_p1;
m2 = cd->mreq;
/*
* The requests are chained
* in the m_nextpkt list.
*/
while (m2 != NULL &&
m2->m_nextpkt != NULL)
/* Find end of list. */
m2 = m2->m_nextpkt;
if (m2 != NULL)
m2->m_nextpkt =
ct->ct_record;
else
cd->mreq =
ct->ct_record;
ct->ct_record->m_nextpkt =
NULL;
ct->ct_record = NULL;
xprt_active(xprt);
mtx_unlock(&ct->ct_lock);
}
} else {
mtx_lock(&ct->ct_lock);
foundreq = 0;
TAILQ_FOREACH(cr, &ct->ct_pending,
cr_link) {
if (cr->cr_xid ==
xid_plus_direction[0]) {
/*
* This one
* matches. We leave
* the reply mbuf in
* cr->cr_mrep. Set
* the XID to zero so
* that we will ignore
* any duplicated
* replies.
*/
cr->cr_xid = 0;
cr->cr_mrep =
ct->ct_record;
cr->cr_error = 0;
foundreq = 1;
wakeup(cr);
break;
}
}
mtx_unlock(&ct->ct_lock);
if (!foundreq)
m_freem(ct->ct_record);
ct->ct_record = NULL;
}
}
}
} while (m);
ct->ct_upcallrefs--;
if (ct->ct_upcallrefs < 0)
panic("rpcvc upcall refcnt");
if (ct->ct_upcallrefs == 0)
wakeup(&ct->ct_upcallrefs);
return (SU_OK);
}
/*
* Wait for all upcalls in progress to complete.
*/
static void
clnt_vc_upcallsdone(struct ct_data *ct)
{
SOCKBUF_LOCK_ASSERT(&ct->ct_socket->so_rcv);
while (ct->ct_upcallrefs > 0)
(void) msleep(&ct->ct_upcallrefs,
SOCKBUF_MTX(&ct->ct_socket->so_rcv), 0, "rpcvcup", 0);
}
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