xref: /freebsd/sbin/nfsiod/nfsiod.c (revision ae83180158c4c937f170e31eff311b18c0286a93)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static const char copyright[] =
39 "@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif
42 
43 #ifndef lint
44 #if 0
45 static char sccsid[] = "@(#)nfsiod.c	8.4 (Berkeley) 5/3/95";
46 #endif
47 static const char rcsid[] =
48   "$FreeBSD$";
49 #endif
50 
51 #include <sys/param.h>
52 #include <sys/syslog.h>
53 #include <sys/wait.h>
54 #include <sys/linker.h>
55 #include <sys/mount.h>
56 #include <sys/sysctl.h>
57 
58 #include <err.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <unistd.h>
62 
63 #define	MAXNFSDCNT      20
64 
65 static void
66 usage(void)
67 {
68 	(void)fprintf(stderr, "usage: nfsiod [-n num_servers]\n");
69 	exit(1);
70 }
71 
72 int
73 main(int argc, char *argv[])
74 {
75 	int ch;
76 	struct xvfsconf vfc;
77 	int error;
78 	unsigned int iodmin, iodmax, num_servers;
79 	size_t len;
80 
81 	error = getvfsbyname("nfs", &vfc);
82 	if (error) {
83 		if (kldload("nfs") == -1)
84 			err(1, "kldload(nfs)");
85 		error = getvfsbyname("nfs", &vfc);
86 	}
87 	if (error)
88 		errx(1, "NFS support is not available in the running kernel");
89 
90 	num_servers = 0;
91 	while ((ch = getopt(argc, argv, "n:")) != -1)
92 		switch (ch) {
93 		case 'n':
94 			num_servers = atoi(optarg);
95 			if (num_servers < 1) {
96 				warnx("nfsiod count %d; reset to %d",
97 				    num_servers, 1);
98 				num_servers = 1;
99 			}
100 			if (num_servers > MAXNFSDCNT) {
101 				warnx("nfsiod count %d; reset to %d",
102 				    num_servers, MAXNFSDCNT);
103 				num_servers = MAXNFSDCNT;
104 			}
105 			break;
106 		case '?':
107 		default:
108 			usage();
109 		}
110 	argc -= optind;
111 	argv += optind;
112 
113 	if (argc > 0)
114 		usage();
115 
116 	if (num_servers == 0)
117 		exit(0);		/* no change */
118 
119 	len = sizeof iodmin;
120 	error = sysctlbyname("vfs.nfs.iodmin", &iodmin, &len, NULL, 0);
121 	if (error < 0)
122 		err(1, "sysctlbyname(\"vfs.nfs.iodmin\")");
123 	len = sizeof iodmax;
124 	error = sysctlbyname("vfs.nfs.iodmax", &iodmax, &len, NULL, 0);
125 	if (error < 0)
126 		err(1, "sysctlbyname(\"vfs.nfs.iodmin\")");
127 	/* Catch the case where we're lowering num_servers below iodmin */
128 	if (iodmin > num_servers) {
129 		iodmin = num_servers;
130 		error = sysctlbyname("vfs.nfs.iodmin", NULL, 0, &iodmin,
131 		    sizeof iodmin);
132 		if (error < 0)
133 			err(1, "sysctlbyname(\"vfs.nfs.iodmin\")");
134 	}
135 	iodmax = num_servers;
136 	error = sysctlbyname("vfs.nfs.iodmax", NULL, 0, &iodmax, sizeof iodmax);
137 	if (error < 0)
138 		err(1, "sysctlbyname(\"vfs.nfs.iodmax\")");
139 	exit (0);
140 }
141 
142