FreeBSD-5.3/sys/dev/ata/atapi-tape.c
/*-
* Copyright (c) 1998 - 2004 Søren Schmidt <sos@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/dev/ata/atapi-tape.c,v 1.93 2004/08/05 21:11:33 sos Exp $");
#include "opt_ata.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ata.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/mtio.h>
#include <sys/devicestat.h>
#include <sys/sema.h>
#include <sys/taskqueue.h>
#include <vm/uma.h>
#include <machine/bus.h>
#include <dev/ata/ata-all.h>
#include <dev/ata/atapi-tape.h>
/* device structures */
static d_open_t ast_open;
static d_close_t ast_close;
static d_ioctl_t ast_ioctl;
static d_strategy_t ast_strategy;
static struct cdevsw ast_cdevsw = {
.d_version = D_VERSION,
.d_open = ast_open,
.d_close = ast_close,
.d_read = physread,
.d_write = physwrite,
.d_ioctl = ast_ioctl,
.d_strategy = ast_strategy,
.d_name = "ast",
.d_maj = 119,
.d_flags = D_TAPE | D_TRACKCLOSE,
};
/* prototypes */
static void ast_detach(struct ata_device *);
static void ast_start(struct ata_device *);
static int ast_sense(struct ast_softc *);
static void ast_describe(struct ast_softc *);
static void ast_done(struct ata_request *);
static int ast_mode_sense(struct ast_softc *, int, void *, int);
static int ast_mode_select(struct ast_softc *, void *, int);
static int ast_write_filemark(struct ast_softc *, u_int8_t);
static int ast_read_position(struct ast_softc *, int, struct ast_readposition *);
static int ast_space(struct ast_softc *, u_int8_t, int32_t);
static int ast_locate(struct ast_softc *, int, u_int32_t);
static int ast_prevent_allow(struct ast_softc *stp, int);
static int ast_load_unload(struct ast_softc *, u_int8_t);
static int ast_rewind(struct ast_softc *);
static int ast_erase(struct ast_softc *);
static int ast_test_ready(struct ata_device *);
static int ast_wait_dsc(struct ata_device *, int);
/* internal vars */
static u_int32_t ast_lun_map = 0;
static u_int64_t ast_total = 0;
static MALLOC_DEFINE(M_AST, "AST driver", "ATAPI tape driver buffers");
void
ast_attach(struct ata_device *atadev)
{
struct ast_softc *stp;
struct ast_readposition position;
struct cdev *dev;
stp = malloc(sizeof(struct ast_softc), M_AST, M_NOWAIT | M_ZERO);
if (!stp) {
ata_prtdev(atadev, "out of memory\n");
return;
}
stp->device = atadev;
stp->lun = ata_get_lun(&ast_lun_map);
ata_set_name(atadev, "ast", stp->lun);
bioq_init(&stp->queue);
mtx_init(&stp->queue_mtx, "ATAPI TAPE bioqueue lock", NULL, MTX_DEF);
if (ast_sense(stp)) {
free(stp, M_AST);
return;
}
if (!strcmp(atadev->param->model, "OnStream DI-30")) {
struct ast_transferpage transfer;
struct ast_identifypage identify;
stp->flags |= F_ONSTREAM;
bzero(&transfer, sizeof(struct ast_transferpage));
ast_mode_sense(stp, ATAPI_TAPE_TRANSFER_PAGE,
&transfer, sizeof(transfer));
bzero(&identify, sizeof(struct ast_identifypage));
ast_mode_sense(stp, ATAPI_TAPE_IDENTIFY_PAGE,
&identify, sizeof(identify));
strncpy(identify.ident, "FBSD", 4);
ast_mode_select(stp, &identify, sizeof(identify));
ast_read_position(stp, 0, &position);
}
stp->stats = devstat_new_entry("ast", stp->lun, DEV_BSIZE,
DEVSTAT_NO_ORDERED_TAGS,
DEVSTAT_TYPE_SEQUENTIAL | DEVSTAT_TYPE_IF_IDE,
DEVSTAT_PRIORITY_TAPE);
dev = make_dev(&ast_cdevsw, 2 * stp->lun,
UID_ROOT, GID_OPERATOR, 0640, "ast%d", stp->lun);
dev->si_drv1 = stp;
if (atadev->channel->dma)
dev->si_iosize_max = atadev->channel->dma->max_iosize;
else
dev->si_iosize_max = DFLTPHYS;
stp->dev1 = dev;
dev = make_dev(&ast_cdevsw, 2 * stp->lun + 1,
UID_ROOT, GID_OPERATOR, 0640, "nast%d", stp->lun);
dev->si_drv1 = stp;
if (atadev->channel->dma)
dev->si_iosize_max = atadev->channel->dma->max_iosize;
else
dev->si_iosize_max = DFLTPHYS;
stp->dev2 = dev;
/* setup the function ptrs */
atadev->detach = ast_detach;
atadev->start = ast_start;
atadev->softc = stp;
atadev->flags |= ATA_D_MEDIA_CHANGED;
/* announce we are here */
ast_describe(stp);
}
static void
ast_detach(struct ata_device *atadev)
{
struct ast_softc *stp = atadev->softc;
mtx_lock(&stp->queue_mtx);
bioq_flush(&stp->queue, NULL, ENXIO);
mtx_unlock(&stp->queue_mtx);
mtx_destroy(&stp->queue_mtx);
destroy_dev(stp->dev1);
destroy_dev(stp->dev2);
devstat_remove_entry(stp->stats);
ata_prtdev(atadev, "WARNING - removed from configuration\n");
ata_free_name(atadev);
ata_free_lun(&ast_lun_map, stp->lun);
atadev->attach = NULL;
atadev->detach = NULL;
atadev->start = NULL;
atadev->softc = NULL;
atadev->flags = 0;
free(stp, M_AST);
}
static int
ast_sense(struct ast_softc *stp)
{
int count;
/* get drive capabilities, some bugridden drives needs this repeated */
for (count = 0 ; count < 5 ; count++) {
if (!ast_mode_sense(stp, ATAPI_TAPE_CAP_PAGE,
&stp->cap, sizeof(stp->cap)) &&
stp->cap.page_code == ATAPI_TAPE_CAP_PAGE) {
if (stp->cap.blk32k)
stp->blksize = 32768;
if (stp->cap.blk1024)
stp->blksize = 1024;
if (stp->cap.blk512)
stp->blksize = 512;
if (!stp->blksize)
continue;
stp->cap.max_speed = ntohs(stp->cap.max_speed);
stp->cap.max_defects = ntohs(stp->cap.max_defects);
stp->cap.ctl = ntohs(stp->cap.ctl);
stp->cap.speed = ntohs(stp->cap.speed);
stp->cap.buffer_size = ntohs(stp->cap.buffer_size);
return 0;
}
}
return 1;
}
static void
ast_describe(struct ast_softc *stp)
{
if (bootverbose) {
ata_prtdev(stp->device, "<%.40s/%.8s> tape drive at ata%d as %s\n",
stp->device->param->model, stp->device->param->revision,
device_get_unit(stp->device->channel->dev),
(stp->device->unit == ATA_MASTER) ? "master" : "slave");
ata_prtdev(stp->device, "%dKB/s, ", stp->cap.max_speed);
printf("transfer limit %d blk%s, ",
stp->cap.ctl, (stp->cap.ctl > 1) ? "s" : "");
printf("%dKB buffer, ", (stp->cap.buffer_size * DEV_BSIZE) / 1024);
printf("%s\n", ata_mode2str(stp->device->mode));
ata_prtdev(stp->device, "Medium: ");
switch (stp->cap.medium_type) {
case 0x00:
printf("none"); break;
case 0x17:
printf("Travan 1 (400 Mbyte)"); break;
case 0xb6:
printf("Travan 4 (4 Gbyte)"); break;
case 0xda:
printf("OnStream ADR (15Gyte)"); break;
default:
printf("unknown (0x%x)", stp->cap.medium_type);
}
if (stp->cap.readonly) printf(", readonly");
if (stp->cap.reverse) printf(", reverse");
if (stp->cap.eformat) printf(", eformat");
if (stp->cap.qfa) printf(", qfa");
if (stp->cap.lock) printf(", lock");
if (stp->cap.locked) printf(", locked");
if (stp->cap.prevent) printf(", prevent");
if (stp->cap.eject) printf(", eject");
if (stp->cap.disconnect) printf(", disconnect");
if (stp->cap.ecc) printf(", ecc");
if (stp->cap.compress) printf(", compress");
if (stp->cap.blk512) printf(", 512b");
if (stp->cap.blk1024) printf(", 1024b");
if (stp->cap.blk32k) printf(", 32kb");
printf("\n");
}
else {
ata_prtdev(stp->device, "TAPE <%.40s/%.8s> at ata%d-%s %s\n",
stp->device->param->model, stp->device->param->revision,
device_get_unit(stp->device->channel->dev),
(stp->device->unit == ATA_MASTER) ? "master" : "slave",
ata_mode2str(stp->device->mode));
}
}
static int
ast_open(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct ast_softc *stp = dev->si_drv1;
if (!stp || stp->device->flags & ATA_D_DETACHING)
return ENXIO;
if (count_dev(dev) > 1)
return EBUSY;
ast_test_ready(stp->device);
if (stp->cap.lock)
ast_prevent_allow(stp, 1);
if (ast_sense(stp))
ata_prtdev(stp->device, "sense media type failed\n");
stp->device->flags &= ~ATA_D_MEDIA_CHANGED;
stp->flags &= ~(F_DATA_WRITTEN | F_FM_WRITTEN);
ast_total = 0;
return 0;
}
static int
ast_close(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct ast_softc *stp = dev->si_drv1;
/* flush buffers, some drives fail here, they should report ctl = 0 */
if (stp->cap.ctl && (stp->flags & F_DATA_WRITTEN))
ast_write_filemark(stp, 0);
/* write filemark if data written to tape */
if (!(stp->flags & F_ONSTREAM) &&
(stp->flags & (F_DATA_WRITTEN | F_FM_WRITTEN)) == F_DATA_WRITTEN)
ast_write_filemark(stp, ATAPI_WF_WRITE);
/* if minor is even rewind on close */
if (!(minor(dev) & 0x01))
ast_rewind(stp);
if (stp->cap.lock && count_dev(dev) == 1)
ast_prevent_allow(stp, 0);
stp->flags &= ~F_CTL_WARN;
#ifdef AST_DEBUG
ata_prtdev(stp->device, "%ju total bytes transferred\n",
(uintmax_t)ast_total);
#endif
return 0;
}
static int
ast_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
{
struct ast_softc *stp = dev->si_drv1;
int error = 0;
switch (cmd) {
case MTIOCGET:
{
struct mtget *g = (struct mtget *) addr;
bzero(g, sizeof(struct mtget));
g->mt_type = 7;
g->mt_density = 1;
g->mt_blksiz = stp->blksize;
g->mt_comp = stp->cap.compress;
g->mt_density0 = 0; g->mt_density1 = 0;
g->mt_density2 = 0; g->mt_density3 = 0;
g->mt_blksiz0 = 0; g->mt_blksiz1 = 0;
g->mt_blksiz2 = 0; g->mt_blksiz3 = 0;
g->mt_comp0 = 0; g->mt_comp1 = 0;
g->mt_comp2 = 0; g->mt_comp3 = 0;
}
break;
case MTIOCTOP:
{
int i;
struct mtop *mt = (struct mtop *)addr;
switch ((int16_t) (mt->mt_op)) {
case MTWEOF:
for (i=0; i < mt->mt_count && !error; i++)
error = ast_write_filemark(stp, ATAPI_WF_WRITE);
break;
case MTFSF:
if (mt->mt_count)
error = ast_space(stp, ATAPI_SP_FM, mt->mt_count);
break;
case MTBSF:
if (mt->mt_count)
error = ast_space(stp, ATAPI_SP_FM, -(mt->mt_count));
break;
case MTREW:
error = ast_rewind(stp);
break;
case MTOFFL:
error = ast_load_unload(stp, ATAPI_SS_EJECT);
break;
case MTNOP:
error = ast_write_filemark(stp, 0);
break;
case MTERASE:
error = ast_erase(stp);
break;
case MTEOD:
error = ast_space(stp, ATAPI_SP_EOD, 0);
break;
case MTRETENS:
error = ast_load_unload(stp, ATAPI_SS_RETENSION|ATAPI_SS_LOAD);
break;
case MTFSR:
case MTBSR:
case MTCACHE:
case MTNOCACHE:
case MTSETBSIZ:
case MTSETDNSTY:
case MTCOMP:
default:
error = EINVAL;
}
}
break;
case MTIOCRDSPOS:
{
struct ast_readposition position;
if ((error = ast_read_position(stp, 0, &position)))
break;
*(u_int32_t *)addr = position.tape;
}
break;
case MTIOCRDHPOS:
{
struct ast_readposition position;
if ((error = ast_read_position(stp, 1, &position)))
break;
*(u_int32_t *)addr = position.tape;
}
break;
case MTIOCSLOCATE:
error = ast_locate(stp, 0, *(u_int32_t *)addr);
break;
case MTIOCHLOCATE:
error = ast_locate(stp, 1, *(u_int32_t *)addr);
break;
default:
error = ENOTTY;
}
return error;
}
static void
ast_strategy(struct bio *bp)
{
struct ast_softc *stp = bp->bio_dev->si_drv1;
if (stp->device->flags & ATA_D_DETACHING) {
biofinish(bp, NULL, ENXIO);
return;
}
/* if it's a null transfer, return immediatly. */
if (bp->bio_bcount == 0) {
bp->bio_resid = 0;
biodone(bp);
return;
}
if (!(bp->bio_cmd == BIO_READ) && stp->flags & F_WRITEPROTECT) {
biofinish(bp, NULL, EPERM);
return;
}
/* check for != blocksize requests */
if (bp->bio_bcount % stp->blksize) {
ata_prtdev(stp->device, "transfers must be multiple of %d\n",
stp->blksize);
biofinish(bp, NULL, EIO);
return;
}
/* warn about transfers bigger than the device suggests */
if (bp->bio_bcount > stp->blksize * stp->cap.ctl) {
if ((stp->flags & F_CTL_WARN) == 0) {
ata_prtdev(stp->device, "WARNING: CTL exceeded %ld>%d\n",
bp->bio_bcount, stp->blksize * stp->cap.ctl);
stp->flags |= F_CTL_WARN;
}
}
mtx_lock(&stp->queue_mtx);
bioq_insert_tail(&stp->queue, bp);
mtx_unlock(&stp->queue_mtx);
ata_start(stp->device->channel);
}
static void
ast_start(struct ata_device *atadev)
{
struct ast_softc *stp = atadev->softc;
struct bio *bp;
struct ata_request *request;
u_int32_t blkcount;
int8_t ccb[16];
mtx_lock(&stp->queue_mtx);
bp = bioq_first(&stp->queue);
if (!bp) {
mtx_unlock(&stp->queue_mtx);
return;
}
bioq_remove(&stp->queue, bp);
mtx_unlock(&stp->queue_mtx);
bzero(ccb, sizeof(ccb));
if (bp->bio_cmd == BIO_READ)
ccb[0] = ATAPI_READ;
else
ccb[0] = ATAPI_WRITE;
blkcount = bp->bio_bcount / stp->blksize;
ccb[1] = 1;
ccb[2] = blkcount>>16;
ccb[3] = blkcount>>8;
ccb[4] = blkcount;
if (!(request = ata_alloc_request())) {
biofinish(bp, NULL, ENOMEM);
return;
}
request->device = atadev;
request->driver = bp;
bcopy(ccb, request->u.atapi.ccb,
(request->device->param->config & ATA_PROTO_MASK) ==
ATA_PROTO_ATAPI_12 ? 16 : 12);
request->data = bp->bio_data;
request->bytecount = blkcount * stp->blksize;
request->transfersize = min(request->bytecount, 65534);
request->timeout = (ccb[0] == ATAPI_WRITE_BIG) ? 180 : 120;
request->retries = 2;
request->callback = ast_done;
switch (bp->bio_cmd) {
case BIO_READ:
request->flags |= (ATA_R_ATAPI | ATA_R_READ);
break;
case BIO_WRITE:
request->flags |= (ATA_R_ATAPI | ATA_R_WRITE);
break;
default:
ata_prtdev(atadev, "unknown BIO operation\n");
ata_free_request(request);
biofinish(bp, NULL, EIO);
return;
}
devstat_start_transaction_bio(stp->stats, bp);
ata_queue_request(request);
}
static void
ast_done(struct ata_request *request)
{
struct bio *bp = request->driver;
struct ast_softc *stp = request->device->softc;
/* finish up transfer */
if ((bp->bio_error = request->result))
bp->bio_flags |= BIO_ERROR;
if (bp->bio_cmd == BIO_WRITE)
stp->flags |= F_DATA_WRITTEN;
bp->bio_resid = bp->bio_bcount - request->donecount;
ast_total += (bp->bio_bcount - bp->bio_resid);
biofinish(bp, stp->stats, 0);
ata_free_request(request);
}
static int
ast_mode_sense(struct ast_softc *stp, int page, void *pagebuf, int pagesize)
{
int8_t ccb[16] = { ATAPI_MODE_SENSE, 0x08, page, pagesize>>8, pagesize,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int error;
error = ata_atapicmd(stp->device, ccb, pagebuf, pagesize, ATA_R_READ, 10);
#ifdef AST_DEBUG
atapi_dump("ast: mode sense ", pagebuf, pagesize);
#endif
return error;
}
static int
ast_mode_select(struct ast_softc *stp, void *pagebuf, int pagesize)
{
int8_t ccb[16] = { ATAPI_MODE_SELECT, 0x10, 0, pagesize>>8, pagesize,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
#ifdef AST_DEBUG
ata_prtdev(stp->device, "modeselect pagesize=%d\n", pagesize);
atapi_dump("mode select ", pagebuf, pagesize);
#endif
return ata_atapicmd(stp->device, ccb, pagebuf, pagesize, 0, 10);
}
static int
ast_write_filemark(struct ast_softc *stp, u_int8_t function)
{
int8_t ccb[16] = { ATAPI_WEOF, 0x01, 0, 0, function, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0 };
int error;
if (stp->flags & F_ONSTREAM)
ccb[4] = 0x00; /* only flush buffers supported */
else {
if (function) {
if (stp->flags & F_FM_WRITTEN)
stp->flags &= ~F_DATA_WRITTEN;
else
stp->flags |= F_FM_WRITTEN;
}
}
error = ata_atapicmd(stp->device, ccb, NULL, 0, 0, 10);
if (error)
return error;
return ast_wait_dsc(stp->device, 10*60);
}
static int
ast_read_position(struct ast_softc *stp, int hard,
struct ast_readposition *position)
{
int8_t ccb[16] = { ATAPI_READ_POSITION, (hard ? 0x01 : 0), 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0 };
int error;
error = ata_atapicmd(stp->device, ccb, (caddr_t)position,
sizeof(struct ast_readposition), ATA_R_READ, 10);
position->tape = ntohl(position->tape);
position->host = ntohl(position->host);
return error;
}
static int
ast_space(struct ast_softc *stp, u_int8_t function, int32_t count)
{
int8_t ccb[16] = { ATAPI_SPACE, function, count>>16, count>>8, count,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
return ata_atapicmd(stp->device, ccb, NULL, 0, 0, 60*60);
}
static int
ast_locate(struct ast_softc *stp, int hard, u_int32_t pos)
{
int8_t ccb[16] = { ATAPI_LOCATE, 0x01 | (hard ? 0x4 : 0), 0,
pos>>24, pos>>16, pos>>8, pos,
0, 0, 0, 0, 0, 0, 0, 0, 0 };
int error;
error = ata_atapicmd(stp->device, ccb, NULL, 0, 0, 10);
if (error)
return error;
return ast_wait_dsc(stp->device, 60*60);
}
static int
ast_prevent_allow(struct ast_softc *stp, int lock)
{
int8_t ccb[16] = { ATAPI_PREVENT_ALLOW, 0, 0, 0, lock,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
return ata_atapicmd(stp->device, ccb, NULL, 0, 0, 30);
}
static int
ast_load_unload(struct ast_softc *stp, u_int8_t function)
{
int8_t ccb[16] = { ATAPI_START_STOP, 0x01, 0, 0, function, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0 };
int error;
if ((function & ATAPI_SS_EJECT) && !stp->cap.eject)
return 0;
error = ata_atapicmd(stp->device, ccb, NULL, 0, 0, 10);
if (error)
return error;
tsleep((caddr_t)&error, PRIBIO, "astlu", 1 * hz);
if (function == ATAPI_SS_EJECT)
return 0;
return ast_wait_dsc(stp->device, 60*60);
}
static int
ast_rewind(struct ast_softc *stp)
{
int8_t ccb[16] = { ATAPI_REZERO, 0x01, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0 };
int error;
error = ata_atapicmd(stp->device, ccb, NULL, 0, 0, 10);
if (error)
return error;
return ast_wait_dsc(stp->device, 60*60);
}
static int
ast_erase(struct ast_softc *stp)
{
int8_t ccb[16] = { ATAPI_ERASE, 3, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0 };
int error;
if ((error = ast_rewind(stp)))
return error;
return ata_atapicmd(stp->device, ccb, NULL, 0, 0, 60*60);
}
static int
ast_test_ready(struct ata_device *atadev)
{
int8_t ccb[16] = { ATAPI_TEST_UNIT_READY, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
return ata_atapicmd(atadev, ccb, NULL, 0, 0, 30);
}
static int
ast_wait_dsc(struct ata_device *atadev, int timeout)
{
int error = 0;
int8_t ccb[16] = { ATAPI_POLL_DSC, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
timeout *= hz;
while (timeout > 0) {
error = ata_atapicmd(atadev, ccb, NULL, 0, 0, 0);
if (error != EBUSY)
break;
tsleep(&error, PRIBIO, "atpwt", hz / 2);
timeout -= (hz / 2);
}
return error;
}