From 6feb6a4c157d48f2e40de4116d96cfc05726231e Mon Sep 17 00:00:00 2001 From: iedowse Date: Tue, 16 Oct 2001 21:55:53 +0000 Subject: When nfsd was started with only UDP servers, the master nfsd would spin in a loop eating CPU time. This bug has existed since the TI-RPC import. The problem is that we should only enter the select loop if at least one TCP server was started. Fix this by having the master nfsd become a UDP server itself if there are no TCP servers. Also improve/correct the code for cleaning up slave nfsd processes and unregistering with rpcbind when the master nfsd exits. One issue that remains open is that if a slave nfsd dies, then all nfsds will shut down. This is because nfssvc() in the master nfsd returns 0 when the master nfsd receives a SIGCHLD. Submitted by: tmm --- sbin/nfsd/nfsd.c | 182 ++++++++++++++++++++++++++++++++----------------------- 1 file changed, 106 insertions(+), 76 deletions(-) (limited to 'sbin/nfsd') diff --git a/sbin/nfsd/nfsd.c b/sbin/nfsd/nfsd.c index a00dc88..bb67b54 100644 --- a/sbin/nfsd/nfsd.c +++ b/sbin/nfsd/nfsd.c @@ -52,6 +52,8 @@ static const char rcsid[] = #include #include #include +#include +#include #include #include @@ -64,6 +66,7 @@ static const char rcsid[] = #include #include +#include #include #include #include @@ -86,12 +89,16 @@ pid_t children[MAXNFSDCNT]; /* PIDs of children */ int nfsdcnt; /* number of children */ void cleanup(int); +void child_cleanup(int); void killchildren(void); -void nonfs (int); -void reapchild (int); -int setbindhost (struct addrinfo **ia, const char *bindhost, struct addrinfo hints); -void unregistration (void); -void usage (void); +void nfsd_exit(int); +void nonfs(int); +void reapchild(int); +int setbindhost(struct addrinfo **ia, const char *bindhost, + struct addrinfo hints); +void start_server(int); +void unregistration(void); +void usage(void); /* * Nfs server daemon mostly just a user context for nfssvc() @@ -126,13 +133,12 @@ main(argc, argv, envp) fd_set ready, sockbits; fd_set v4bits, v6bits; int ch, connect_type_cnt, i, len, maxsock, msgsock; - int nfssvc_flag, on = 1, unregister, reregister, sock; + int on = 1, unregister, reregister, sock; int tcp6sock, ip6flag, tcpflag, tcpsock; - int udpflag, ecode, s; - int bindhostc = 0, bindanyflag, rpcbreg, rpcbregcnt; + int udpflag, ecode, s, srvcnt; + int bindhostc, bindanyflag, rpcbreg, rpcbregcnt; char **bindhost = NULL; pid_t pid; - int error; if (modfind("nfsserver") < 0) { /* Not present in kernel, try loading it */ @@ -141,8 +147,8 @@ main(argc, argv, envp) } nfsdcnt = DEFNFSDCNT; - unregister = reregister = tcpflag = 0; - bindanyflag = udpflag; + unregister = reregister = tcpflag = maxsock = 0; + bindanyflag = udpflag = connect_type_cnt = bindhostc = 0; #define GETOPT "ah:n:rdtu" #define USAGE "[-ardtu] [-n num_servers] [-h bindip]" while ((ch = getopt(argc, argv, GETOPT)) != -1) @@ -313,8 +319,6 @@ main(argc, argv, envp) daemon(0, 0); (void)signal(SIGHUP, SIG_IGN); (void)signal(SIGINT, SIG_IGN); - (void)signal(SIGSYS, nonfs); - (void)signal(SIGUSR1, cleanup); /* * nfsd sits in the kernel most of the time. It needs * to ignore SIGTERM/SIGQUIT in order to stay alive as long @@ -324,40 +328,31 @@ main(argc, argv, envp) (void)signal(SIGTERM, SIG_IGN); (void)signal(SIGQUIT, SIG_IGN); } + (void)signal(SIGSYS, nonfs); (void)signal(SIGCHLD, reapchild); - openlog("nfsd:", LOG_PID, LOG_DAEMON); + openlog("nfsd", LOG_PID, LOG_DAEMON); - for (i = 0; i < nfsdcnt; i++) { + /* If we use UDP only, we start the last server below. */ + srvcnt = tcpflag ? nfsdcnt : nfsdcnt - 1; + for (i = 0; i < srvcnt; i++) { switch ((pid = fork())) { case -1: syslog(LOG_ERR, "fork: %m"); - killchildren(); - exit (1); + nfsd_exit(1); case 0: break; default: children[i] = pid; continue; } - + (void)signal(SIGUSR1, child_cleanup); setproctitle("server"); - nfssvc_flag = NFSSVC_NFSD; - nsd.nsd_nfsd = NULL; - while (nfssvc(nfssvc_flag, &nsd) < 0) { - if (errno) { - syslog(LOG_ERR, "nfssvc: %m"); - exit(1); - } - nfssvc_flag = NFSSVC_NFSD; - } - exit(0); + + start_server(0); } - if (atexit(killchildren) == -1) { - syslog(LOG_ERR, "atexit: %s", strerror(errno)); - exit(1); - } + (void)signal(SIGUSR1, cleanup); FD_ZERO(&v4bits); FD_ZERO(&v6bits); @@ -379,14 +374,14 @@ main(argc, argv, envp) ai_udp->ai_protocol)) < 0) { syslog(LOG_ERR, "can't create udp socket"); - exit(1); + nfsd_exit(1); } if (bind(sock, ai_udp->ai_addr, ai_udp->ai_addrlen) < 0) { syslog(LOG_ERR, "can't bind udp addr %s: %m", bindhost[i]); - exit(1); + nfsd_exit(1); } freeaddrinfo(ai_udp); nfsdargs.sock = sock; @@ -394,7 +389,7 @@ main(argc, argv, envp) nfsdargs.namelen = 0; if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) { syslog(LOG_ERR, "can't Add UDP socket"); - exit(1); + nfsd_exit(1); } (void)close(sock); } @@ -409,7 +404,7 @@ main(argc, argv, envp) if (ecode != 0) { syslog(LOG_ERR, "getaddrinfo udp: %s", gai_strerror(ecode)); - exit(1); + nfsd_exit(1); } nconf_udp = getnetconfigent("udp"); if (nconf_udp == NULL) @@ -440,7 +435,7 @@ main(argc, argv, envp) ai_udp6->ai_protocol)) < 0) { syslog(LOG_ERR, "can't create udp6 socket"); - exit(1); + nfsd_exit(1); } if (setsockopt(sock, IPPROTO_IPV6, IPV6_BINDV6ONLY, @@ -448,14 +443,14 @@ main(argc, argv, envp) syslog(LOG_ERR, "can't set v6-only binding for " "udp6 socket: %m"); - exit(1); + nfsd_exit(1); } if (bind(sock, ai_udp6->ai_addr, ai_udp6->ai_addrlen) < 0) { syslog(LOG_ERR, "can't bind udp6 addr %s: %m", bindhost[i]); - exit(1); + nfsd_exit(1); } freeaddrinfo(ai_udp6); nfsdargs.sock = sock; @@ -464,7 +459,7 @@ main(argc, argv, envp) if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) { syslog(LOG_ERR, "can't add UDP6 socket"); - exit(1); + nfsd_exit(1); } (void)close(sock); } @@ -479,7 +474,7 @@ main(argc, argv, envp) if (ecode != 0) { syslog(LOG_ERR, "getaddrinfo udp6: %s", gai_strerror(ecode)); - exit(1); + nfsd_exit(1); } nconf_udp6 = getnetconfigent("udp6"); if (nconf_udp6 == NULL) @@ -509,7 +504,7 @@ main(argc, argv, envp) 0)) < 0) { syslog(LOG_ERR, "can't create tpc socket"); - exit(1); + nfsd_exit(1); } if (setsockopt(tcpsock, SOL_SOCKET, SO_REUSEADDR, @@ -521,11 +516,11 @@ main(argc, argv, envp) syslog(LOG_ERR, "can't bind tcp addr %s: %m", bindhost[i]); - exit(1); + nfsd_exit(1); } if (listen(tcpsock, 5) < 0) { syslog(LOG_ERR, "listen failed"); - exit(1); + nfsd_exit(1); } freeaddrinfo(ai_tcp); FD_SET(tcpsock, &sockbits); @@ -545,7 +540,7 @@ main(argc, argv, envp) if (ecode != 0) { syslog(LOG_ERR, "getaddrinfo tcp: %s", gai_strerror(ecode)); - exit(1); + nfsd_exit(1); } nconf_tcp = getnetconfigent("tcp"); if (nconf_tcp == NULL) @@ -577,7 +572,7 @@ main(argc, argv, envp) ai_tcp6->ai_protocol)) < 0) { syslog(LOG_ERR, "can't create tcp6 socket"); - exit(1); + nfsd_exit(1); } if (setsockopt(tcp6sock, SOL_SOCKET, SO_REUSEADDR, @@ -589,18 +584,18 @@ main(argc, argv, envp) syslog(LOG_ERR, "can't set v6-only binding for tcp6 " "socket: %m"); - exit(1); + nfsd_exit(1); } if (bind(tcp6sock, ai_tcp6->ai_addr, ai_tcp6->ai_addrlen) < 0) { syslog(LOG_ERR, "can't bind tcp6 addr %s: %m", bindhost[i]); - exit(1); + nfsd_exit(1); } if (listen(tcp6sock, 5) < 0) { syslog(LOG_ERR, "listen failed"); - exit(1); + nfsd_exit(1); } freeaddrinfo(ai_tcp6); FD_SET(tcp6sock, &sockbits); @@ -620,7 +615,7 @@ main(argc, argv, envp) if (ecode != 0) { syslog(LOG_ERR, "getaddrinfo tcp6: %s", gai_strerror(ecode)); - exit(1); + nfsd_exit(1); } nconf_tcp6 = getnetconfigent("tcp6"); if (nconf_tcp6 == NULL) @@ -636,15 +631,24 @@ main(argc, argv, envp) if (rpcbregcnt == 0) { syslog(LOG_ERR, "rpcb_set() failed, nothing to do: %m"); - exit(1); + nfsd_exit(1); } - if ((tcpflag) && (connect_type_cnt == 0)) { + if (tcpflag && connect_type_cnt == 0) { syslog(LOG_ERR, "tcp connects == 0, nothing to do: %m"); - exit(1); + nfsd_exit(1); } setproctitle("master"); + /* + * We always want a master to have a clean way to to shut nfsd down + * (with unregistration): if the master is killed, it unregisters and + * kills all children. If we run for UDP only (and so do not have to + * loop waiting waiting for accept), we instead make the parent + * a "server" too. start_server will not return. + */ + if (!tcpflag) + start_server(1); /* * Loop forever accepting connections and passing the sockets @@ -656,7 +660,7 @@ main(argc, argv, envp) if (select(maxsock + 1, &ready, NULL, NULL, NULL) < 1) { syslog(LOG_ERR, "select failed: %m"); - exit(1); + nfsd_exit(1); } } for (tcpsock = 0; tcpsock <= maxsock; tcpsock++) { @@ -666,7 +670,7 @@ main(argc, argv, envp) if ((msgsock = accept(tcpsock, (struct sockaddr *)&inetpeer, &len)) < 0) { syslog(LOG_ERR, "accept failed: %m"); - exit(1); + nfsd_exit(1); } memset(inetpeer.sin_zero, 0, sizeof(inetpeer.sin_zero)); @@ -676,7 +680,7 @@ main(argc, argv, envp) "setsockopt SO_KEEPALIVE: %m"); nfsdargs.sock = msgsock; nfsdargs.name = (caddr_t)&inetpeer; - nfsdargs.namelen = sizeof(inetpeer); + nfsdargs.namelen = len; nfssvc(NFSSVC_ADDSOCK, &nfsdargs); (void)close(msgsock); } else if (FD_ISSET(tcpsock, &v6bits)) { @@ -686,7 +690,7 @@ main(argc, argv, envp) &len)) < 0) { syslog(LOG_ERR, "accept failed: %m"); - exit(1); + nfsd_exit(1); } if (setsockopt(msgsock, SOL_SOCKET, SO_KEEPALIVE, (char *)&on, @@ -695,7 +699,7 @@ main(argc, argv, envp) "SO_KEEPALIVE: %m"); nfsdargs.sock = msgsock; nfsdargs.name = (caddr_t)&inet6peer; - nfsdargs.namelen = sizeof(inet6peer); + nfsdargs.namelen = len; nfssvc(NFSSVC_ADDSOCK, &nfsdargs); (void)close(msgsock); } @@ -767,8 +771,14 @@ void reapchild(signo) int signo; { + pid_t pid; + int i; - while (wait3(NULL, WNOHANG, NULL) > 0); + while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) { + for (i = 0; i < nfsdcnt; i++) + if (pid == children[i]) + children[i] = -1; + } } void @@ -783,32 +793,52 @@ void killchildren() { int i; - sigset_t sigs; - sigemptyset(&sigs); - /* - * Block SIGCHLD to avoid killing a reaped process (although it is - * unlikely, the pid might have been reused). - */ - sigaddset(&sigs, SIGCHLD); - if (sigprocmask(SIG_BLOCK, &sigs, NULL) == -1) { - syslog(LOG_ERR, "sigprocmask: %s", - strerror(errno)); - return; - } for (i = 0; i < nfsdcnt; i++) { if (children[i] > 0) kill(children[i], SIGKILL); } - if (sigprocmask(SIG_UNBLOCK, &sigs, NULL) == -1) { - syslog(LOG_ERR, "sigprocmask: %s", strerror(errno)); - } - unregistration(); } +/* + * Cleanup master after SIGUSR1. + */ void cleanup(signo) { + nfsd_exit(0); +} + +/* + * Cleanup child after SIGUSR1. + */ +void +child_cleanup(signo) +{ + exit(0); +} + +void +nfsd_exit(int status) +{ killchildren(); - exit (0); + unregistration(); + exit(status); +} + +void +start_server(int master) +{ + int status; + + status = 0; + nsd.nsd_nfsd = NULL; + if (nfssvc(NFSSVC_NFSD, &nsd) < 0) { + syslog(LOG_ERR, "nfssvc: %m"); + status = 1; + } + if (master) + nfsd_exit(status); + else + exit(status); } -- cgit v1.1