/* setmax.c - aeb, 000326 - use on 2.4.0test9 or newer */
/* IBM part thanks to Matan Ziv-Av <matan@svgalib.org> */
/*
* Results on Maxtor disks:
* The jumper that clips capacity does not influence the value returned
* by READ_NATIVE_MAX_ADDRESS, so it is possible to set the jumper
* and let the kernel, or a utility (like this one) run at boot time
* restore full capacity.
* For example, run "setmax -d 0 /dev/hdX" for suitable X.
* Kernel patches exist that do the same.
*
* Results on IBM disks:
* The jumper that clips capacity is ruthless. You clipped capacity.
* However, if your BIOS hangs on a large disk, do not use the jumper
* but find another machine and use a utility (like this one) to
* clip the non-volatile max address.
* For example, run "setmax -m 66055248 /dev/hdX" for suitable X.
* Now go back to your first machine and proceed as with Maxtor drives above.
*/
#include <stdio.h>
#include <fcntl.h>
#include <getopt.h>
#include <linux/hdreg.h>
#ifndef HDIO_DRIVE_CMD_AEB
#define HDIO_DRIVE_CMD_AEB 0x031e
#endif
#define INITIALIZE_DRIVE_PARAMETERS 0x91
#define READ_NATIVE_MAX_ADDRESS 0xf8
#define CHECK_POWER_MODE 0xe5
#define SET_MAX 0xf9
#define LBA 0x40
#define VV 1 /* if set in sectorct then NOT volatile */
struct idecmdin {
unsigned char cmd;
unsigned char feature;
unsigned char nsect;
unsigned char sect, lcyl, hcyl;
unsigned char select;
};
struct idecmdout {
unsigned char status;
unsigned char error;
unsigned char nsect;
unsigned char sect, lcyl, hcyl;
unsigned char select;
};
unsigned int
tolba(unsigned char *args) {
return ((args[6] & 0xf) << 24) + (args[5] << 16) + (args[4] << 8) + args[3];
}
void
fromlba(unsigned char *args, unsigned int lba) {
args[3] = (lba & 0xff);
lba >>= 8;
args[4] = (lba & 0xff);
lba >>= 8;
args[5] = (lba & 0xff);
lba >>= 8;
args[6] = (args[6] & 0xf0) | (lba & 0xf);
}
int
get_identity(int fd) {
unsigned char args[4+512] = {WIN_IDENTIFY,0,0,1,};
struct hd_driveid *id = (struct hd_driveid *)&args[4];
if (ioctl(fd, HDIO_DRIVE_CMD, &args)) {
perror("HDIO_DRIVE_CMD");
fprintf(stderr,
"WIN_IDENTIFY failed - trying WIN_PIDENTIFY\n");
args[0] = WIN_PIDENTIFY;
if (ioctl(fd, HDIO_DRIVE_CMD, &args)) {
perror("HDIO_DRIVE_CMD");
fprintf(stderr,
"WIN_PIDENTIFY also failed - giving up\n");
exit(1);
}
}
printf("lba capacity: %d sectors (%lld bytes)\n",
id->lba_capacity,
(long long) id->lba_capacity * 512);
}
/*
* result: in LBA mode precisely what is expected
* in CHS mode the correct H and S, and C mod 65536.
*/
unsigned int
get_native_max(int fd, int slave) {
unsigned char args[7];
int i, max;
for (i=0; i<7; i++)
args[i] = 0;
args[0] = READ_NATIVE_MAX_ADDRESS;
args[6] = (slave ? 0x10 : 0) | LBA;
if (ioctl(fd, HDIO_DRIVE_CMD_AEB, &args)) {
perror("HDIO_DRIVE_CMD_AEB failed READ_NATIVE_MAX_ADDRESS");
for (i=0; i<7; i++)
printf("%d = 0x%x\n", args[i], args[i]);
exit(1);
}
return tolba(args);
}
/*
* SET_MAX_ADDRESS requires immediately preceding READ_NATIVE_MAX_ADDRESS
*
* On old Maxtor disk: this fails for delta <= 254, succeeds for delta >= 255.
* (So, in order to get the last 255*512=130560 bytes back one has to reboot.
* Side effect: reset to CurCHS=16383/16/63, CurSects=16514064.)
* On new Maxtor disk: this works.
* On IBM disk without jumper: this works.
*/
void
set_max_address(int fd, int slave, int delta, int max, int volat) {
unsigned char args[7];
int i, nativemax, newmax;
nativemax = get_native_max(fd, slave);
printf("nativemax=%d (0x%x)\n", nativemax, nativemax);
for (i=0; i<7; i++)
args[i] = 0;
args[0] = SET_MAX;
args[1] = 0;
args[2] = (volat ? 0 : 1);
if (delta != -1)
newmax = nativemax-delta;
else
newmax = max-1;
fromlba(args, newmax);
args[6] |= LBA;
if (ioctl(fd, HDIO_DRIVE_CMD_AEB, &args)) {
perror("HDIO_DRIVE_CMD_AEB failed SET_MAX");
for (i=0; i<7; i++)
printf("%d = 0x%x\n", args[i], args[i]);
exit(1);
}
}
static char short_opts[] = "d:m:";
static const struct option long_opts[] = {
{ "delta", required_argument, NULL, 'd' },
{ "max", required_argument, NULL, 'm' },
{ NULL, 0, NULL, 0 }
};
static char *usage_txt =
"Call: setmax [-d D] [-m M] DEVICE\n"
"\n"
"The call \"setmax --max M DEVICE\" will do a SET_MAX command\n"
"to set the non-volatile max number of accessible sectors to M.\n"
"\n"
"The call \"setmax --delta D DEVICE\" will do a SET_MAX command\n"
"to set the maximum accessible sector number D sectors\n"
"below end-of-disk.\n"
"\n"
"The call \"setmax DEVICE\" will do a READ_NATIVE_MAX_ADDRESS\n"
"command, and report the maximum accessible sector number.\n"
"\n"
"This is IDE-only. Probably DEVICE is /dev/hdx for some x.\n\n";
main(int argc, char **argv){
int fd, c;
int delta, max, volat;
/* If you modify device, also update slave, if necessary. */
/* The kernel already does this for us since 2.4.0test9. */
/* master: hda, hdc, hde; slave: hdb, hdd, hdf */
char *device = NULL; /* e.g. "/dev/hda" */
int slave = 0;
delta = max = volat = -1;
while ((c = getopt_long (argc, argv, short_opts, long_opts, NULL)) != -1) {
switch(c) {
case 'd':
delta = atoi(optarg);
volat = 1;
break;
case 'm':
max = atoi(optarg);
volat = 0;
break;
case '?':
default:
fprintf(stderr, "unknown option\n");
fprintf(stderr, usage_txt);
exit(1);
}
}
if (optind < argc)
device = argv[optind];
if (!device) {
fprintf(stderr, "no device specified - "
"use e.g. \"setmax /dev/hdb\"\n");
fprintf(stderr, usage_txt);
exit(1);
}
printf("Using device %s\n", device);
fd = open(device, O_RDONLY);
if (fd == -1) {
perror("open");
exit(1);
}
if (delta != -1 || max != -1) {
if (delta != -1)
printf("setting delta=%d\n", delta);
else
printf("setting max=%d\n", max);
set_max_address(fd, slave, delta, max, volat);
} else {
int mad = get_native_max(fd, slave);
long long bytes = (long long) (mad+1) * 512;
int hMB = (bytes+50000000)/100000000;
printf("native max address: %d\n", mad);
printf("that is %lld bytes, %d.%d GB\n",
bytes, hMB/10, hMB%10);
}
get_identity(fd);
return 0;
}
