/*- * 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; CLIENT *newclient = NULL; mtx_lock(&rc->rc_lock); while (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 (rc->rc_closed) { mtx_unlock(&rc->rc_lock); return (RPC_CANTSEND); } if (rc->rc_client) { mtx_unlock(&rc->rc_lock); return (RPC_SUCCESS); } /* * My turn to attempt a connect. The rc_connecting variable * serializes the following code sequence, so it is guaranteed * that rc_client will still be NULL after it is re-locked below, * since that is the only place it is set non-NULL. */ rc->rc_connecting = TRUE; mtx_unlock(&rc->rc_lock); oldcred = td->td_ucred; td->td_ucred = rc->rc_ucred; so = __rpc_nconf2socket(rc->rc_nconf); if (!so) { stat = rpc_createerr.cf_stat = RPC_TLIERROR; rpc_createerr.cf_error.re_errno = 0; td->td_ucred = oldcred; goto out; } if (rc->rc_privport) bindresvport(so, NULL); if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS) newclient = clnt_dg_create(so, (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers, rc->rc_sendsz, rc->rc_recvsz); else newclient = clnt_vc_create(so, (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers, rc->rc_sendsz, rc->rc_recvsz, rc->rc_intr); td->td_ucred = oldcred; if (!newclient) { soclose(so); rc->rc_err = rpc_createerr.cf_error; stat = rpc_createerr.cf_stat; goto out; } CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0); CLNT_CONTROL(newclient, CLSET_CONNECT, &one); CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout); CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry); CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan); CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr); stat = RPC_SUCCESS; out: mtx_lock(&rc->rc_lock); KASSERT(rc->rc_client == NULL, ("rc_client not null")); if (!rc->rc_closed) { rc->rc_client = newclient; newclient = NULL; } rc->rc_connecting = FALSE; wakeup(rc); mtx_unlock(&rc->rc_lock); if (newclient) { /* * It has been closed, so discard the new client. * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot * be called with the rc_lock mutex held, since they may * msleep() while holding a different mutex. */ CLNT_CLOSE(newclient); CLNT_RELEASE(newclient); } 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, error; tries = 0; do { mtx_lock(&rc->rc_lock); if (rc->rc_closed) { mtx_unlock(&rc->rc_lock); return (RPC_CANTSEND); } if (!rc->rc_client) { mtx_unlock(&rc->rc_lock); stat = clnt_reconnect_connect(cl); if (stat == RPC_SYSTEMERROR) { error = tsleep(&fake_wchan, rc->rc_intr ? PCATCH | PBDRY : 0, "rpccon", hz); if (error == EINTR || error == ERESTART) return (RPC_INTR); 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); } 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)) { CLNT_RELEASE(client); break; } } if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND || stat == RPC_CANTRECV) { tries++; if (tries >= rc->rc_retries) { CLNT_RELEASE(client); 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 by checking if rc_client has changed. * If not, we are done with the client and must * do CLNT_RELEASE(client) twice to dispose of it, * because there is both an initial refcnt and one * acquired by CLNT_ACQUIRE() above. */ if (rc->rc_client == client) { rc->rc_client = NULL; mtx_unlock(&rc->rc_lock); CLNT_RELEASE(client); } else { mtx_unlock(&rc->rc_lock); } CLNT_RELEASE(client); } else { CLNT_RELEASE(client); 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; } /* * Since this function requires that rc_client be valid, it can * only be called when that is guaranteed to be the case. */ 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) { } /* * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must * always be called before CLNT_CALL_MBUF() by a single thread only. */ 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)); }