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/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
/* ts A61010 */
/* #include <a ssert.h> */
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
/* #include <m alloc.h> ts A61013 : not in Linux man 3 malloc */
#include <string.h>
#include <sys/poll.h>
#include <linux/hdreg.h>
#include <stdlib.h>
#include <scsi/sg.h>
#include <scsi/scsi.h>
#include "transport.h"
#include "drive.h"
#include "sg.h"
#include "spc.h"
#include "mmc.h"
#include "sbc.h"
#include "debug.h"
#include "toc.h"
#include "util.h"
/* kludge! glibc headers don't define all the SCSI stuff that we use! */
#ifndef SG_GET_ACCESS_COUNT
# define SG_GET_ACCESS_COUNT 0x2289
#endif
#include "libdax_msgs.h"
extern struct libdax_msgs *libdax_messenger;
static void enumerate_common(char *fname, int bus_no, int host_no,
int channel_no, int target_no, int lun_no);
/* ts A51221 */
int burn_drive_is_banned(char *device_address);
/* ts A60813 : storage objects are in libburn/init.c
wether to use O_EXCL
wether to use O_NOBLOCK with open(2) on devices
wether to take O_EXCL rejection as fatal error */
extern int burn_sg_open_o_excl;
extern int burn_sg_open_o_nonblock;
extern int burn_sg_open_abort_busy;
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
int mmc_function_spy(char * text);
static int sgio_test(int fd)
{
unsigned char test_ops[] = { 0, 0, 0, 0, 0, 0 };
sg_io_hdr_t s;
memset(&s, 0, sizeof(sg_io_hdr_t));
s.interface_id = 'S';
s.dxfer_direction = SG_DXFER_NONE;
s.cmd_len = 6;
s.cmdp = test_ops;
s.timeout = 12345;
return ioctl(fd, SG_IO, &s);
}
/* ts A60925 : ticket 74 */
int sg_close_drive_fd(char *fname, int driveno, int *fd, int sorry)
{
int ret, os_errno, sevno= LIBDAX_MSGS_SEV_DEBUG;
char msg[4096+100];
if(*fd < 0)
return(0);
ret = close(*fd);
*fd = -1337;
if(ret != -1)
return 1;
os_errno= errno;
if (fname != NULL)
sprintf(msg, "Encountered error when closing drive '%s'",
fname);
else
sprintf(msg, "Encountered error when closing drive");
if (sorry)
sevno = LIBDAX_MSGS_SEV_SORRY;
libdax_msgs_submit(libdax_messenger, driveno, 0x00020002,
sevno, LIBDAX_MSGS_PRIO_HIGH, msg, os_errno, 0);
return 0;
}
/* ts A60924 */
int sg_handle_busy_device(char *fname, int os_errno)
{
char msg[4096];
/* ts A60814 : i saw no way to do this more nicely */
if (burn_sg_open_abort_busy) {
fprintf(stderr,
"\nlibburn: FATAL : Application triggered abort on busy device '%s'\n",
fname);
/* ts A61007 */
abort();
/* a ssert("drive busy" == "non fatal"); */
}
/* ts A60924 : now reporting to libdax_msgs */
sprintf(msg, "Cannot open busy device '%s'", fname);
libdax_msgs_submit(libdax_messenger, -1, 0x00020001,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_LOW,
msg, os_errno, 0);
return 1;
}
/* ts A60922 ticket 33 */
/** Returns the next index number and the next enumerated drive address.
@param idx An opaque handle. Make no own theories about it.
@param adr Takes the reply
@param adr_size Gives maximum size of reply including final 0
@param initialize 1 = start new,
0 = continue, use no other values for now
-1 = finish
@return 1 = reply is a valid address , 0 = no further address available
-1 = severe error (e.g. adr_size too small)
*/
int sg_give_next_adr(burn_drive_enumerator_t *idx,
char adr[], int adr_size, int initialize)
{
/* sg.h : typedef int burn_drive_enumerator_t; */
static int sg_limit = 32, ata_limit = 26;
int baseno = 0;
if (initialize == -1)
return 0;
if (initialize == 1)
*idx = -1;
(*idx)++;
if (*idx >= sg_limit)
goto next_ata;
if (adr_size < 10)
return -1;
sprintf(adr, "/dev/sg%d", *idx);
return 1;
next_ata:;
baseno += sg_limit;
if (*idx - baseno >= ata_limit)
goto next_nothing;
if (adr_size < 9)
return -1;
sprintf(adr, "/dev/hd%c", 'a' + (*idx - baseno));
return 1;
next_nothing:;
baseno += ata_limit;
return 0;
}
int sg_is_enumerable_adr(char *adr)
{
char fname[4096];
int i, ret = 0, first = 1;
while (1) {
ret= sg_give_next_adr(&i, fname, sizeof(fname), first);
if(ret <= 0)
break;
first = 0;
if (strcmp(adr, fname) == 0)
return 1;
}
return(0);
}
/* ts A60926 */
int sg_release_siblings(int sibling_fds[], int *sibling_count)
{
int i;
char msg[81];
for(i= 0; i < *sibling_count; i++)
sg_close_drive_fd(NULL, -1, &(sibling_fds[i]), 0);
if(*sibling_count > 0) {
sprintf(msg, "Closed %d O_EXCL scsi siblings", *sibling_count);
libdax_msgs_submit(libdax_messenger, -1, 0x00020007,
LIBDAX_MSGS_SEV_NOTE, LIBDAX_MSGS_PRIO_HIGH, msg, 0,0);
}
*sibling_count = 0;
return 1;
}
/* ts A60926 */
int sg_open_drive_fd(char *fname, int scan_mode)
{
int open_mode = O_RDWR, fd;
char msg[81];
/* ts A60813 - A60927
O_EXCL with devices is a non-POSIX feature
of Linux kernels. Possibly introduced 2002.
Mentioned in "The Linux SCSI Generic (sg) HOWTO" */
if(burn_sg_open_o_excl)
open_mode |= O_EXCL;
/* ts A60813
O_NONBLOCK was already hardcoded in ata_ but not in sg_.
There must be some reason for this. So O_NONBLOCK is
default mode for both now. Disable on own risk. */
if(burn_sg_open_o_nonblock)
open_mode |= O_NONBLOCK;
/* <<< debugging
fprintf(stderr,
"\nlibburn: experimental: o_excl= %d , o_nonblock= %d, abort_on_busy= %d\n",
burn_sg_open_o_excl,burn_sg_open_o_nonblock,burn_sg_open_abort_busy);
fprintf(stderr,
"libburn: experimental: O_EXCL= %d , O_NONBLOCK= %d\n",
!!(open_mode&O_EXCL),!!(open_mode&O_NONBLOCK));
*/
fd = open(fname, open_mode);
if (fd == -1) {
/* <<< debugging
fprintf(stderr,
"\nlibburn: experimental: fname= %s , errno= %d\n",
fname,errno);
*/
if (errno == EBUSY) {
sg_handle_busy_device(fname, errno);
return -1;
}
if (scan_mode)
return -1;
sprintf(msg, "Failed to open device '%s'",fname);
libdax_msgs_submit(libdax_messenger, -1, 0x00020005,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
msg, errno, 0);
return -1;
}
return fd;
}
/* ts A60926 */
int sg_open_scsi_siblings(char *path, int driveno,
int sibling_fds[], int *sibling_count,
int host_no, int channel_no, int id_no, int lun_no)
{
int tld, i, ret, fd, i_bus_no = -1;
int i_host_no = -1, i_channel_no = -1, i_target_no = -1, i_lun_no = -1;
char msg[161], fname[81];
static char tldev[][81]= {"/dev/sr%d", "/dev/scd%d", "/dev/st%d", ""};
if(host_no < 0 || id_no < 0 || channel_no < 0 || lun_no < 0)
return(2);
if(*sibling_count > 0)
sg_release_siblings(sibling_fds, sibling_count);
for (tld = 0; tldev[tld][0] != 0; tld++) {
for (i = 0; i < 32; i++) {
sprintf(fname, tldev[tld], i);
ret = sg_obtain_scsi_adr(fname, &i_bus_no, &i_host_no,
&i_channel_no, &i_target_no, &i_lun_no);
if (ret <= 0)
continue;
if (i_host_no != host_no || i_channel_no != channel_no)
continue;
if (i_target_no != id_no || i_lun_no != lun_no)
continue;
fd = sg_open_drive_fd(fname, 0);
if (fd < 0)
goto failed;
if (*sibling_count>=LIBBURN_SG_MAX_SIBLINGS) {
sprintf(msg, "Too many scsi siblings of '%s'",
path);
libdax_msgs_submit(libdax_messenger,
driveno, 0x00020006,
LIBDAX_MSGS_SEV_FATAL,
LIBDAX_MSGS_PRIO_HIGH, msg, 0, 0);
goto failed;
}
sprintf(msg, "Opened O_EXCL scsi sibling '%s' of '%s'",
fname, path);
libdax_msgs_submit(libdax_messenger, driveno,
0x00020004,
LIBDAX_MSGS_SEV_NOTE, LIBDAX_MSGS_PRIO_HIGH,
msg, 0, 0);
sibling_fds[*sibling_count] = fd;
(*sibling_count)++;
}
}
return(1);
failed:;
sg_release_siblings(sibling_fds, sibling_count);
return 0;
}
/* ts A60926 */
int sg_close_drive(struct burn_drive *d)
{
int ret;
if (!burn_drive_is_open(d))
return 0;
sg_release_siblings(d->sibling_fds, &(d->sibling_count));
ret = sg_close_drive_fd(d->devname, d->global_index, &(d->fd), 0);
return ret;
}
void ata_enumerate(void)
{
struct hd_driveid tm;
int i, fd;
char fname[10];
for (i = 0; i < 26; i++) {
sprintf(fname, "/dev/hd%c", 'a' + i);
/* ts A51221 */
if (burn_drive_is_banned(fname))
continue;
fd = sg_open_drive_fd(fname, 1);
if (fd == -1)
continue;
/* found a drive */
ioctl(fd, HDIO_GET_IDENTITY, &tm);
/* not atapi */
if (!(tm.config & 0x8000) || (tm.config & 0x4000)) {
sg_close_drive_fd(fname, -1, &fd, 0);
continue;
}
/* if SG_IO fails on an atapi device, we should stop trying to
use hd* devices */
if (sgio_test(fd) == -1) {
sg_close_drive_fd(fname, -1, &fd, 0);
return;
}
if (sg_close_drive_fd(fname, -1, &fd, 1) <= 0)
continue;
enumerate_common(fname, -1, -1, -1, -1, -1);
}
}
void sg_enumerate(void)
{
struct sg_scsi_id sid;
int i, fd, sibling_fds[LIBBURN_SG_MAX_SIBLINGS], sibling_count= 0, ret;
int bus_no = -1;
char fname[10];
for (i = 0; i < 32; i++) {
sprintf(fname, "/dev/sg%d", i);
/* ts A51221 */
if (burn_drive_is_banned(fname))
continue;
/* ts A60927 */
fd = sg_open_drive_fd(fname, 1);
if (fd == -1)
continue;
/* found a drive */
ioctl(fd, SG_GET_SCSI_ID, &sid);
#ifdef SCSI_IOCTL_GET_BUS_NUMBER
/* Hearsay A61005 */
if (ioctl(fd, SCSI_IOCTL_GET_BUS_NUMBER, &bus_no) == -1)
bus_no = -1;
#endif
if (sg_close_drive_fd(fname, -1, &fd,
sid.scsi_type == TYPE_ROM ) <= 0)
continue;
if (sid.scsi_type != TYPE_ROM)
continue;
/* ts A60927 : trying to do locking with growisofs */
if(burn_sg_open_o_excl>1) {
ret = sg_open_scsi_siblings(
fname, -1, sibling_fds, &sibling_count,
sid.host_no, sid.channel,
sid.scsi_id, sid.lun);
if (ret<=0) {
sg_handle_busy_device(fname, 0);
continue;
}
/* the final occupation will be done in sg_grab() */
sg_release_siblings(sibling_fds, &sibling_count);
}
#ifdef SCSI_IOCTL_GET_BUS_NUMBER
if(bus_no == -1)
bus_no = 1000 * (sid.host_no + 1) + sid.channel;
#else
bus_no = sid.host_no;
#endif
enumerate_common(fname, bus_no, sid.host_no, sid.channel,
sid.scsi_id, sid.lun);
}
}
/* ts A60923 - A61005 : introduced new SCSI parameters */
static void enumerate_common(char *fname, int bus_no, int host_no,
int channel_no, int target_no, int lun_no)
{
int i;
struct burn_drive *t;
struct burn_drive out;
/* ts A60923 */
out.bus_no = bus_no;
out.host = host_no;
out.id = target_no;
out.channel = channel_no;
out.lun = lun_no;
out.devname = burn_strdup(fname);
out.fd = -1337;
out.sibling_count = 0;
for(i= 0; i<LIBBURN_SG_MAX_SIBLINGS; i++)
out.sibling_fds[i] = -1337;
/* ts A61020 */
out.start_lba= -2000000000;
out.end_lba= -2000000000;
out.read_atip = mmc_read_atip;
out.grab = sg_grab;
out.release = sg_release;
out.issue_command = sg_issue_command;
out.getcaps = spc_getcaps;
out.released = 1;
out.status = BURN_DISC_UNREADY;
out.eject = sbc_eject;
out.load = sbc_load;
out.lock = spc_prevent;
out.unlock = spc_allow;
out.read_disc_info = spc_sense_write_params;
out.get_erase_progress = spc_get_erase_progress;
out.test_unit_ready = spc_test_unit_ready;
out.probe_write_modes = spc_probe_write_modes;
out.read_toc = mmc_read_toc;
out.write = mmc_write;
out.erase = mmc_erase;
out.read_sectors = mmc_read_sectors;
out.perform_opc = mmc_perform_opc;
out.set_speed = mmc_set_speed;
out.send_parameters = spc_select_error_params;
out.send_write_parameters = spc_select_write_params;
out.send_cue_sheet = mmc_send_cue_sheet;
out.sync_cache = mmc_sync_cache;
out.get_nwa = mmc_get_nwa;
out.close_disc = mmc_close_disc;
out.close_session = mmc_close_session;
out.idata = malloc(sizeof(struct burn_scsi_inquiry_data));
out.idata->valid = 0;
out.mdata = malloc(sizeof(struct scsi_mode_data));
out.mdata->valid = 0;
/* ts A61007 : obsolete Assert in drive_getcaps() */
if(out.idata == NULL || out.mdata == NULL) {
libdax_msgs_submit(libdax_messenger, -1, 0x00020108,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
"Could not allocate new drive object", 0, 0);
return;
}
memset(&out.params, 0, sizeof(struct params));
t = burn_drive_register(&out);
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("enumerate_common : -------- doing grab");
/* try to get the drive info */
if (sg_grab(t)) {
burn_print(2, "getting drive info\n");
t->getcaps(t);
t->unlock(t);
t->released = 1;
} else {
burn_print(2, "unable to grab new located drive\n");
burn_drive_unregister(t);
}
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("enumerate_common : ----- would release ");
}
/*
we use the sg reference count to decide whether we can use the
drive or not.
if refcount is not one, drive is open somewhere else.
ts A60813: this test is too late. O_EXCL is the stronger solution.
After all the test was disabled already in icculus.org/burn CVS.
*/
int sg_grab(struct burn_drive *d)
{
int fd, count, os_errno= 0, ret;
/* ts A60813 */
int open_mode = O_RDWR;
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("sg_grab");
/* ts A60813 - A60927
O_EXCL with devices is a non-POSIX feature
of Linux kernels. Possibly introduced 2002.
Mentioned in "The Linux SCSI Generic (sg) HOWTO".
*/
if(burn_sg_open_o_excl)
open_mode |= O_EXCL;
/* ts A60813
O_NONBLOCK was hardcoded here. So it should stay default mode. */
if(burn_sg_open_o_nonblock)
open_mode |= O_NONBLOCK;
/* ts A60813
After enumeration the drive fd is probably still open.
-1337 is the initial value of burn_drive.fd and the value after
relase of drive. Unclear why not the official error return
value -1 of open(2) war used. */
/* ts A60822: was if(d->fd == -1337) { */
if(! burn_drive_is_open(d)) {
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("sg_grab ----------- opening");
/* ts A60926 */
if(burn_sg_open_o_excl>1) {
fd = -1;
ret = sg_open_scsi_siblings(d->devname,
d->global_index,d->sibling_fds,
&(d->sibling_count),
d->host, d->channel, d->id, d->lun);
if(ret <= 0)
goto drive_is_in_use;
}
fd = open(d->devname, open_mode);
os_errno = errno;
} else
fd= d->fd;
/* ts A61007 : this is redundant */
/* a ssert(fd != -1337); */
if (fd >= 0) {
/* ts A60814:
according to my experiments this test would work now ! */
/* ts A60926 : this was disabled */
/* Tests with growisofs on kernel 2.4.21 yielded that this
does not help against blocking on busy drives.
*/
/* <<< the old dummy */
/* er = ioctl(fd, SG_GET_ACCESS_COUNT, &count);*/
count = 1;
if (1 == count) {
d->fd = fd;
fcntl(fd, F_SETOWN, getpid());
d->released = 0;
return 1;
}
drive_is_in_use:;
libdax_msgs_submit(libdax_messenger, d->global_index,
0x00020003,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
"Could not grab drive - already in use", 0, 0);
sg_close_drive(d);
d->fd = -1337;
return 0;
}
libdax_msgs_submit(libdax_messenger, d->global_index, 0x00020003,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
"Could not grab drive", os_errno, 0);
return 0;
}
/*
non zero return means you still have the drive and it's not
in a state to be released? (is that even possible?)
*/
int sg_release(struct burn_drive *d)
{
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("sg_release");
if (d->fd < 1) {
burn_print(1, "release an ungrabbed drive. die\n");
return 0;
}
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("sg_release ----------- closing");
sg_close_drive(d);
return 0;
}
int sg_issue_command(struct burn_drive *d, struct command *c)
{
int done = 0, no_c_page = 0;
int err;
sg_io_hdr_t s;
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
char buf[161];
sprintf(buf,"sg_issue_command d->fd= %d d->released= %d\n",
d->fd,d->released);
mmc_function_spy(buf);
/* ts A61010 : with no fd there is no chance to send an ioctl */
if (d->fd < 0) {
c->error = 1;
return 0;
}
c->error = 0;
memset(&s, 0, sizeof(sg_io_hdr_t));
s.interface_id = 'S';
if (c->dir == TO_DRIVE)
s.dxfer_direction = SG_DXFER_TO_DEV;
else if (c->dir == FROM_DRIVE)
s.dxfer_direction = SG_DXFER_FROM_DEV;
else if (c->dir == NO_TRANSFER) {
s.dxfer_direction = SG_DXFER_NONE;
/* ts A61007 */
/* a ssert(!c->page); */
no_c_page = 1;
}
s.cmd_len = c->oplen;
s.cmdp = c->opcode;
s.mx_sb_len = 32;
s.sbp = c->sense;
memset(c->sense, 0, sizeof(c->sense));
s.timeout = 200000;
if (c->page && !no_c_page) {
s.dxferp = c->page->data;
if (c->dir == FROM_DRIVE) {
s.dxfer_len = BUFFER_SIZE;
/* touch page so we can use valgrind */
memset(c->page->data, 0, BUFFER_SIZE);
} else {
/* ts A61010 */
/* a ssert(c->page->bytes > 0); */
if (c->page->bytes <= 0) {
c->error = 1;
return 0;
}
s.dxfer_len = c->page->bytes;
}
} else {
s.dxferp = NULL;
s.dxfer_len = 0;
}
s.usr_ptr = c;
do {
err = ioctl(d->fd, SG_IO, &s);
/* ts A61010 */
/* a ssert(err != -1); */
if (err == -1) {
libdax_msgs_submit(libdax_messenger,
d->global_index, 0x0002010c,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
"Failed to transfer command to drive",
errno, 0);
sg_close_drive(d);
d->released = 1;
d->busy = BURN_DRIVE_IDLE;
c->error = 1;
return -1;
}
if (s.sb_len_wr) {
if (!c->retry) {
c->error = 1;
return 1;
}
switch (scsi_error(d, s.sbp, s.sb_len_wr)) {
case RETRY:
done = 0;
break;
case FAIL:
done = 1;
c->error = 1;
break;
}
} else {
done = 1;
}
} while (!done);
return 1;
}
enum response scsi_error(struct burn_drive *d, unsigned char *sense,
int senselen)
{
int key, asc, ascq;
senselen = senselen;
key = sense[2];
asc = sense[12];
ascq = sense[13];
burn_print(12, "CONDITION: 0x%x 0x%x 0x%x on %s %s\n",
key, asc, ascq, d->idata->vendor, d->idata->product);
switch (asc) {
case 0:
burn_print(12, "NO ERROR!\n");
return RETRY;
case 2:
burn_print(1, "not ready\n");
return RETRY;
case 4:
burn_print(1,
"logical unit is in the process of becoming ready\n");
return RETRY;
case 0x20:
if (key == 5)
burn_print(1, "bad opcode\n");
return FAIL;
case 0x21:
burn_print(1, "invalid address or something\n");
return FAIL;
case 0x24:
if (key == 5)
burn_print(1, "invalid field in cdb\n");
else
break;
return FAIL;
case 0x26:
if ( key == 5 )
burn_print( 1, "invalid field in parameter list\n" );
return FAIL;
case 0x28:
if (key == 6)
burn_print(1,
"Not ready to ready change, medium may have changed\n");
else
break;
return RETRY;
case 0x3A:
burn_print(12, "Medium not present in %s %s\n",
d->idata->vendor, d->idata->product);
d->status = BURN_DISC_EMPTY;
return FAIL;
}
burn_print(1, "unknown failure\n");
burn_print(1, "key:0x%x, asc:0x%x, ascq:0x%x\n", key, asc, ascq);
return FAIL;
}
/* ts A60922 */
/** Try to obtain SCSI address parameters.
@return 1 is success , 0 is failure
*/
int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
int *target_no, int *lun_no)
{
int fd, ret;
struct my_scsi_idlun {
int x;
int host_unique_id;
};
struct my_scsi_idlun idlun;
if (strncmp(path, "/dev/hd", 7) == 0
&& path[7] >= 'a' && path[7] <= 'z' && path[8] == 0)
return 0; /* on RIP 14 all hdx return SCSI adr 0,0,0,0 */
fd = open(path, O_RDONLY | O_NONBLOCK);
if(fd < 0)
return 0;
#ifdef SCSI_IOCTL_GET_BUS_NUMBER
/* Hearsay A61005 */
if (ioctl(fd, SCSI_IOCTL_GET_BUS_NUMBER, bus_no) == -1)
*bus_no = -1;
#endif
/* http://www.tldp.org/HOWTO/SCSI-Generic-HOWTO/scsi_g_idlun.html */
ret = ioctl(fd, SCSI_IOCTL_GET_IDLUN, &idlun);
sg_close_drive_fd(path, -1, &fd, 0);
if (ret == -1)
return(0);
*host_no= (idlun.x>>24)&255;
*channel_no= (idlun.x>>16)&255;
*target_no= (idlun.x)&255;
*lun_no= (idlun.x>>8)&255;
#ifdef SCSI_IOCTL_GET_BUS_NUMBER
if(*bus_no == -1)
*bus_no = 1000 * (*host_no + 1) + *channel_no;
#else
*bus_no= *host_no;
#endif
return 1;
}