diskctl(8) tool

commands/diskctl/Makefile

@@ -0,0 +1,4 @@
+PROG=	diskctl
+MAN=
+
+.include <bsd.prog.mk>

commands/diskctl/diskctl.c

@@ -0,0 +1,100 @@
+/* diskctl - control disk device driver parameters - by D.C. van Moolenbroek */
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+static char *name, *dev;
+
+static void usage(void)
+{
+	fprintf(stderr, "usage: %s <device> <command> [args]\n"
+			"\n"
+			"supported commands:\n"
+			"  getwcache           return write cache status\n"
+			"  setwcache [on|off]  set write cache status\n"
+			"  flush               flush write cache\n",
+			name);
+
+	exit(EXIT_FAILURE);
+}
+
+static int open_dev(int flags)
+{
+	int fd;
+
+	fd = open(dev, flags);
+
+	if (fd < 0) {
+		perror("open");
+
+		exit(EXIT_FAILURE);
+	}
+
+	return fd;
+}
+
+int main(int argc, char **argv)
+{
+	int fd, val;
+
+	name = argv[0];
+
+	if (argc < 3) usage();
+
+	dev = argv[1];
+
+	if (!strcasecmp(argv[2], "getwcache")) {
+		if (argc != 3) usage();
+
+		fd = open_dev(O_RDONLY);
+
+		if (ioctl(fd, DIOCGETWC, &val) != 0) {
+			perror("ioctl");
+
+			return EXIT_FAILURE;
+		}
+
+		close(fd);
+
+		printf("write cache is %s\n", val ? "on" : "off");
+	}
+	else if (!strcasecmp(argv[2], "setwcache")) {
+		if (argc != 4) usage();
+
+		fd = open_dev(O_WRONLY);
+
+		if (!strcasecmp(argv[3], "on")) val = 1;
+		else if (!strcasecmp(argv[3], "off")) val = 0;
+		else usage();
+
+		if (ioctl(fd, DIOCSETWC, &val) != 0) {
+			perror("ioctl");
+
+			return EXIT_FAILURE;
+		}
+
+		close(fd);
+
+		printf("write cache %sabled\n", val ? "en" : "dis");
+	}
+	else if (!strcasecmp(argv[2], "flush")) {
+		if (argc != 3) usage();
+
+		fd = open_dev(O_WRONLY);
+
+		if (ioctl(fd, DIOCFLUSH, NULL) != 0) {
+			perror("ioctl");
+
+			return EXIT_FAILURE;
+		}
+
+		close(fd);
+
+		printf("write cache flushed\n");
+	}
+	else usage();
+
+	return EXIT_SUCCESS;
+}