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#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <linux/fs.h>
#include <sys/ioctl.h>
#include <asm/errno.h>
#include "mpdev.h"
typedef enum mpdev_cmds_s {
FAIL,
RECOVER,
UNKNOWN=99
} mpdev_cmd;
char filename[128];
mpdev_cmd cmd_arg=UNKNOWN;
int fd=-1;
void useage(void)
{
printf("mp: Tells the Multipath ramdisk device driver (mpdev.o)\n");
printf(" which i/o paths are to be failed or recovered.\n");
printf("\n");
printf("Syntax:\n");
printf("\tmp [cmd|?|help] device_name\n");
printf("\n");
printf("Examples:\n");
printf("\tmp fail /dev/mpa ... will fail any i/o to the device\n");
printf("\tmp recover /dev/mpa ... will allow i/o to the device\n");
printf("\n");
printf("Notes on installing the ramdisk:\n");
printf("\tCreate new device nodes ... mknod /dev/mpa b 252 0\n");
printf("\t mknod /dev/mpb b 252 1\n");
printf("\tAdd alias to /etc/modules.conf... alias block-major-252 mpdev\n");
printf("\tCopy mpdev to /lib/modules ... mkdir /lib/modules/2.4.18/misc/\n");
printf("\t cp mpdev.o /lib/modules/2.4.18/misc/\n\n");
}
int parse_args(int argc, char **argv)
{
int rc=0;
if (argc != 3) return EINVAL;
if ( (strncmp(argv[1],"fail",4)==0) ||
(strncmp(argv[1],"FAIL",4)==0)) {
cmd_arg = FAIL;
} else if ( (strncmp(argv[1],"recover",7)==0) ||
(strncmp(argv[1],"RECOVER",7)==0)) {
cmd_arg = RECOVER;
}
switch (cmd_arg) {
case FAIL:
case RECOVER:
strncpy(filename, argv[2], 127 );
if ( strlen(filename) == 0 ) {
rc = EINVAL;
} else {
rc = 0;
}
break;
default:
rc= EINVAL;
break;
}
return rc;
}
int open_device(int *fd)
{
*fd = open(filename, O_RDONLY | O_NONBLOCK);
return(errno);
}
int close_device(int fd)
{
if ( close (fd) != 0 ) {
fprintf (stderr, "mpdev device close failed: %s\n", strerror (errno));
}
return(errno);
}
int fail(int fd)
{
mpdev_cmd_t cmd = {1,0};
int status;
int rc=0;
status = ioctl (fd, MPDEV_CMD, &cmd);
if (status) {
fprintf(stderr, "fail cmd failed rc= %s\n", strerror(errno));
rc = errno;
} else if ( cmd.status ) {
fprintf(stderr, "fail cmd failed rc= %d\n", cmd.status );
rc = cmd.status;
}
return rc;
}
int recover(int fd)
{
mpdev_cmd_t cmd = {0,0};
int status;
int rc=0;
status = ioctl (fd, MPDEV_CMD, &cmd);
if (status) {
fprintf(stderr, "recover cmd failed rc= %s\n", strerror(errno));
rc = errno;
} else if ( cmd.status ) {
fprintf(stderr, "recover cmd failed rc= %d\n", cmd.status );
rc = cmd.status;
}
return rc;
}
int main (int argc, char **argv)
{
int fd;
int rc=0;
if ( argc == 2 ) {
if ( (strcmp(argv[1], "?")==0) ||
(strcmp(argv[1], "-?")==0) ||
(strcmp(argv[1], "help")==0) ||
(strcmp(argv[1], "HELP")==0) ||
(strcmp(argv[1], "-help")==0) ||
(strcmp(argv[1], "-HELP")==0)) {
useage();
return 0;
}
} else if (argc==1) {
useage();
return 0;
}
if ( parse_args(argc, argv) ) {
useage();
return 0;
}
if ( open_device(&fd) == 0 ) {
switch (cmd_arg) {
case FAIL:
rc = fail(fd);
break;
case RECOVER:
rc = recover(fd);
break;
default:
rc = EINVAL;
break;
}
if (!rc) fsync(fd);
close_device(fd);
} else {
fprintf(stderr, "device open failed\n" );
}
if (!rc) {
printf("Success\n");
}
return(rc);
}
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