Home | History | Annotate | Line # | Download | only in swapctl
swapctl.c revision 1.9 
      1 /*	$NetBSD: swapctl.c,v 1.9 1998/07/26 20:23:15 mycroft Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1996, 1997 Matthew R. Green
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. The name of the author may not be used to endorse or promote products
     16  *    derived from this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     28  * SUCH DAMAGE.
     29  */
     30 
     31 /*
     32  * swapctl command:
     33  *	-A		add all devices listed as `sw' in /etc/fstab
     34  *	-t [blk|noblk]	if -A, add either all block device or all non-block
     35  *			devices
     36  *	-a <dev>	add this device
     37  *	-d <dev>	remove this swap device (not supported yet)
     38  *	-l		list swap devices
     39  *	-s		short listing of swap devices
     40  *	-k		use kilobytes
     41  *	-p <pri>	use this priority
     42  *	-c		change priority
     43  *
     44  * or, if invoked as "swapon" (compatibility mode):
     45  *
     46  *	-a		all devices listed as `sw' in /etc/fstab
     47  *	-t		same as -t above (feature not present in old
     48  *			swapon(8) command)
     49  *	<dev>		add this device
     50  */
     51 
     52 #include <sys/param.h>
     53 #include <sys/stat.h>
     54 
     55 #include <vm/vm_swap.h>
     56 
     57 #include <unistd.h>
     58 #include <err.h>
     59 #include <errno.h>
     60 #include <stdio.h>
     61 #include <stdlib.h>
     62 #include <string.h>
     63 #include <fstab.h>
     64 
     65 #include "swapctl.h"
     66 
     67 int	command;
     68 
     69 /*
     70  * Commands for swapctl(8).  These are mutually exclusive.
     71  */
     72 #define	CMD_A		0x01	/* process /etc/fstab */
     73 #define	CMD_a		0x02	/* add a swap file/device */
     74 #define	CMD_c		0x04	/* change priority of a swap file/device */
     75 #define	CMD_d		0x08	/* delete a swap file/device */
     76 #define	CMD_l		0x10	/* list swap files/devices */
     77 #define	CMD_s		0x20	/* summary of swap files/devices */
     78 
     79 #define	SET_COMMAND(cmd) \
     80 do { \
     81 	if (command) \
     82 		usage(); \
     83 	command = (cmd); \
     84 } while (0)
     85 
     86 /*
     87  * Commands that require a "path" argument at the end of the command
     88  * line, and the ones which require that none exist.
     89  */
     90 #define	REQUIRE_PATH	(CMD_a | CMD_c | CMD_d)
     91 #define	REQUIRE_NOPATH	(CMD_A | CMD_l | CMD_s)
     92 
     93 /*
     94  * Option flags, and the commands with which they are valid.
     95  */
     96 int	kflag;		/* display in 1K blocks */
     97 #define	KFLAG_CMDS	(CMD_l | CMD_s)
     98 
     99 int	pflag;		/* priority was specified */
    100 #define	PFLAG_CMDS	(CMD_A | CMD_a | CMD_c)
    101 
    102 char	*tflag;		/* swap device type (blk or noblk) */
    103 #define	TFLAG_CMDS	(CMD_A)
    104 
    105 int	pri;		/* uses 0 as default pri */
    106 
    107 static	void change_priority __P((char *));
    108 static	void add_swap __P((char *));
    109 static	void del_swap __P((char *));
    110 	int  main __P((int, char *[]));
    111 static	void do_fstab __P((void));
    112 static	void usage __P((void));
    113 static	void swapon_command __P((int, char **));
    114 #if 0
    115 static	void swapoff_command __P((int, char **));
    116 #endif
    117 
    118 extern	char *__progname;	/* from crt0.o */
    119 
    120 int
    121 main(argc, argv)
    122 	int	argc;
    123 	char	*argv[];
    124 {
    125 	int	c;
    126 
    127 	if (strcmp(__progname, "swapon") == 0) {
    128 		swapon_command(argc, argv);
    129 		/* NOTREACHED */
    130 	}
    131 
    132 #if 0
    133 	if (strcmp(__progname, "swapoff") == 0) {
    134 		swapoff_command(argc, argv);
    135 		/* NOTREACHED */
    136 	}
    137 #endif
    138 
    139 	while ((c = getopt(argc, argv, "Aacdlkp:st:")) != -1) {
    140 		switch (c) {
    141 		case 'A':
    142 			SET_COMMAND(CMD_A);
    143 			break;
    144 
    145 		case 'a':
    146 			SET_COMMAND(CMD_a);
    147 			break;
    148 
    149 		case 'c':
    150 			SET_COMMAND(CMD_c);
    151 			break;
    152 
    153 		case 'd':
    154 			SET_COMMAND(CMD_d);
    155 			break;
    156 
    157 		case 'l':
    158 			SET_COMMAND(CMD_l);
    159 			break;
    160 
    161 		case 'k':
    162 			kflag = 1;
    163 			break;
    164 
    165 		case 'p':
    166 			pflag = 1;
    167 			/* XXX strtol() */
    168 			pri = atoi(optarg);
    169 			break;
    170 
    171 		case 's':
    172 			SET_COMMAND(CMD_s);
    173 			break;
    174 
    175 		case 't':
    176 			if (tflag != NULL)
    177 				usage();
    178 			tflag = optarg;
    179 			break;
    180 
    181 		default:
    182 			usage();
    183 			/* NOTREACHED */
    184 		}
    185 	}
    186 
    187 	/* Did the user specify a command? */
    188 	if (command == 0)
    189 		usage();
    190 
    191 	argv += optind;
    192 	argc -= optind;
    193 
    194 	switch (argc) {
    195 	case 0:
    196 		if (command & REQUIRE_PATH)
    197 			usage();
    198 		break;
    199 
    200 	case 1:
    201 		if (command & REQUIRE_NOPATH)
    202 			usage();
    203 		break;
    204 
    205 	default:
    206 		usage();
    207 	}
    208 
    209 	/* To change priority, you have to specify one. */
    210 	if ((command == CMD_c) && pflag == 0)
    211 		usage();
    212 
    213 	/* Sanity-check -t */
    214 	if (tflag != NULL) {
    215 		if (command != CMD_A)
    216 			usage();
    217 		if (strcmp(tflag, "blk") != 0 &&
    218 		    strcmp(tflag, "noblk") != 0)
    219 			usage();
    220 	}
    221 
    222 	/* Dispatch the command. */
    223 	switch (command) {
    224 	case CMD_l:
    225 		list_swap(pri, kflag, pflag, 0, 1);
    226 		break;
    227 
    228 	case CMD_s:
    229 		list_swap(pri, kflag, pflag, 0, 0);
    230 		break;
    231 
    232 	case CMD_c:
    233 		change_priority(argv[0]);
    234 		break;
    235 
    236 	case CMD_a:
    237 		add_swap(argv[0]);
    238 		break;
    239 
    240 	case CMD_d:
    241 		del_swap(argv[0]);
    242 		break;
    243 
    244 	case CMD_A:
    245 		do_fstab();
    246 		break;
    247 	}
    248 
    249 	exit(0);
    250 }
    251 
    252 /*
    253  * swapon_command: emulate the old swapon(8) program.
    254  */
    255 void
    256 swapon_command(argc, argv)
    257 	int argc;
    258 	char **argv;
    259 {
    260 	int ch, fiztab = 0;
    261 
    262 	while ((ch = getopt(argc, argv, "at:")) != -1) {
    263 		switch (ch) {
    264 		case 'a':
    265 			fiztab = 1;
    266 			break;
    267 		case 't':
    268 			if (tflag != NULL)
    269 				usage();
    270 			tflag = optarg;
    271 			break;
    272 		default:
    273 			goto swapon_usage;
    274 		}
    275 	}
    276 	argc -= optind;
    277 	argv += optind;
    278 
    279 	if (fiztab) {
    280 		if (argc)
    281 			goto swapon_usage;
    282 		/* Sanity-check -t */
    283 		if (tflag != NULL) {
    284 			if (strcmp(tflag, "blk") != 0 &&
    285 			    strcmp(tflag, "noblk") != 0)
    286 				usage();
    287 		}
    288 		do_fstab();
    289 		exit(0);
    290 	} else if (argc == 0 || tflag != NULL)
    291 		goto swapon_usage;
    292 
    293 	while (argc) {
    294 		add_swap(argv[0]);
    295 		argc--;
    296 		argv++;
    297 	}
    298 	exit(0);
    299 	/* NOTREACHED */
    300 
    301  swapon_usage:
    302 	fprintf(stderr, "usage: %s -a [-t blk|noblk]\n", __progname);
    303 	fprintf(stderr, "       %s <path> ...\n", __progname);
    304 	exit(1);
    305 }
    306 
    307 /*
    308  * change_priority:  change the priority of a swap device.
    309  */
    310 void
    311 change_priority(path)
    312 	char	*path;
    313 {
    314 
    315 	if (swapctl(SWAP_CTL, path, pri) < 0)
    316 		warn("%s", path);
    317 }
    318 
    319 /*
    320  * add_swap:  add the pathname to the list of swap devices.
    321  */
    322 void
    323 add_swap(path)
    324 	char *path;
    325 {
    326 
    327 	if (swapctl(SWAP_ON, path, pri) < 0)
    328 		err(1, "%s", path);
    329 }
    330 
    331 /*
    332  * del_swap:  remove the pathname to the list of swap devices.
    333  */
    334 void
    335 del_swap(path)
    336 	char *path;
    337 {
    338 
    339 	if (swapctl(SWAP_OFF, path, pri) < 0)
    340 		err(1, "%s", path);
    341 }
    342 
    343 void
    344 do_fstab()
    345 {
    346 	struct	fstab *fp;
    347 	char	*s;
    348 	long	priority;
    349 	struct	stat st;
    350 	int	isblk;
    351 	int	gotone = 0;
    352 
    353 #define PRIORITYEQ	"priority="
    354 #define NFSMNTPT	"nfsmntpt="
    355 #define PATH_MOUNT	"/sbin/mount_nfs"
    356 	while ((fp = getfsent()) != NULL) {
    357 		const char *spec;
    358 
    359 		if (strcmp(fp->fs_type, "sw") != 0)
    360 			continue;
    361 
    362 		spec = fp->fs_spec;
    363 		isblk = 0;
    364 
    365 		if ((s = strstr(fp->fs_mntops, PRIORITYEQ)) != NULL) {
    366 			s += sizeof(PRIORITYEQ) - 1;
    367 			priority = atol(s);
    368 		} else
    369 			priority = pri;
    370 
    371 		if ((s = strstr(fp->fs_mntops, NFSMNTPT)) != NULL) {
    372 			char *t, cmd[2*PATH_MAX+sizeof(PATH_MOUNT)+2];
    373 
    374 			/*
    375 			 * Skip this song and dance if we're only
    376 			 * doing block devices.
    377 			 */
    378 			if (tflag != NULL &&
    379 			    strcmp(tflag, "blk") == 0)
    380 				continue;
    381 
    382 			t = strpbrk(s, ",");
    383 			if (t != 0)
    384 				*t = '\0';
    385 			spec = strdup(s + strlen(NFSMNTPT));
    386 			if (t != 0)
    387 				*t = ',';
    388 
    389 			if (spec == NULL)
    390 				errx(1, "Out of memory");
    391 
    392 			if (strlen(spec) == 0) {
    393 				warnx("empty mountpoint");
    394 				free((char *)spec);
    395 				continue;
    396 			}
    397 			snprintf(cmd, sizeof(cmd), "%s %s %s",
    398 				PATH_MOUNT, fp->fs_spec, spec);
    399 			if (system(cmd) != 0) {
    400 				warnx("%s: mount failed", fp->fs_spec);
    401 				continue;
    402 			}
    403 		} else {
    404 			/*
    405 			 * Determine blk-ness.
    406 			 */
    407 			if (stat(spec, &st) < 0) {
    408 				warn(spec);
    409 				continue;
    410 			}
    411 			if (S_ISBLK(st.st_mode))
    412 				isblk = 1;
    413 		}
    414 
    415 		/*
    416 		 * Skip this type if we're told to.
    417 		 */
    418 		if (tflag != NULL) {
    419 			if (strcmp(tflag, "blk") == 0 && isblk == 0)
    420 				continue;
    421 			if (strcmp(tflag, "noblk") == 0 && isblk == 1)
    422 				continue;
    423 		}
    424 
    425 		if (swapctl(SWAP_ON, spec, (int)priority) < 0)
    426 			warn("%s", spec);
    427 		else {
    428 			gotone = 1;
    429 			printf("%s: adding %s as swap device at priority %d\n",
    430 			    __progname, fp->fs_spec, (int)priority);
    431 		}
    432 
    433 		if (spec != fp->fs_spec)
    434 			free((char *)spec);
    435 	}
    436 	if (gotone == 0)
    437 		exit(1);
    438 }
    439 
    440 void
    441 usage()
    442 {
    443 
    444 	fprintf(stderr, "usage: %s -A [-p priority] [-t blk|noblk]\n",
    445 	    __progname);
    446 	fprintf(stderr, "       %s -a [-p priority] path\n", __progname);
    447 	fprintf(stderr, "       %s -c -p priority path\n", __progname);
    448 	fprintf(stderr, "       %s -d path\n", __progname);
    449 	fprintf(stderr, "       %s -l | -s [-k]\n", __progname);
    450 	exit(1);
    451 }
    452