* Copyright (c) 1996, 1997, 1998, 1999, 2004 The NetBSD Foundation, Inc.

/* $NetBSD: ch.c,v 1.95 2021/09/26 14:57:19 thorpej Exp $ */

/*-
* Copyright (c) 1996, 1997, 1998, 1999, 2004 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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>
__KERNEL_RCSID(0, "$NetBSD: ch.c,v 1.95 2021/09/26 14:57:19 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/chio.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/vnode.h>
#include <sys/time.h>
#include <sys/select.h>
#include <sys/poll.h>

#include <dev/scsipi/scsipi_all.h>
#include <dev/scsipi/scsi_all.h>
#include <dev/scsipi/scsi_changer.h>
#include <dev/scsipi/scsiconf.h>

#define CHRETRIES 2
#define CHTIMEOUT (5 * 60 * 1000)

#define CHUNIT(x) (minor((x)))

struct ch_softc {
device_t sc_dev; /* generic device info */
struct scsipi_periph *sc_periph;/* our periph data */

u_int sc_events; /* event bitmask */
struct selinfo sc_selq; /* select/poll queue for events */

int sc_flags; /* misc. info */

int sc_picker; /* current picker */

/*
* The following information is obtained from the
* element address assignment page.
*/
int sc_firsts[4]; /* firsts, indexed by CHET_* */
int sc_counts[4]; /* counts, indexed by CHET_* */

/*
* The following mask defines the legal combinations
* of elements for the MOVE MEDIUM command.
*/
u_int8_t sc_movemask[4];

/*
* As above, but for EXCHANGE MEDIUM.
*/
u_int8_t sc_exchangemask[4];

/*
* Quirks; see below.
*/
int sc_settledelay; /* delay for settle */

};

/* sc_flags */
#define CHF_ROTATE 0x01 /* picker can rotate */

/* Autoconfiguration glue */
static int chmatch(device_t, cfdata_t, void *);
static void chattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(ch, sizeof(struct ch_softc),
chmatch, chattach, NULL, NULL);

extern struct cfdriver ch_cd;

static struct scsipi_inquiry_pattern ch_patterns[] = {
{T_CHANGER, T_REMOV,
"", "", ""},
};

static dev_type_open(chopen);
static dev_type_close(chclose);
static dev_type_read(chread);
static dev_type_ioctl(chioctl);
static dev_type_poll(chpoll);
static dev_type_kqfilter(chkqfilter);

const struct cdevsw ch_cdevsw = {
.d_open = chopen,
.d_close = chclose,
.d_read = chread,
.d_write = nowrite,
.d_ioctl = chioctl,
.d_stop = nostop,
.d_tty = notty,
.d_poll = chpoll,
.d_mmap = nommap,
.d_kqfilter = chkqfilter,
.d_discard = nodiscard,
.d_flag = D_OTHER | D_MPSAFE
};

/* SCSI glue */
static int ch_interpret_sense(struct scsipi_xfer *);

static const struct scsipi_periphsw ch_switch = {
ch_interpret_sense, /* check our error handler first */
NULL, /* no queue; our commands are synchronous */
NULL, /* have no async handler */
NULL, /* nothing to be done when xfer is done */
};

static int ch_move(struct ch_softc *, struct changer_move_request *);
static int ch_exchange(struct ch_softc *,
struct changer_exchange_request *);
static int ch_position(struct ch_softc *,
struct changer_position_request *);
static int ch_ielem(struct ch_softc *);
static int ch_ousergetelemstatus(struct ch_softc *, int, u_int8_t *);
static int ch_usergetelemstatus(struct ch_softc *,
struct changer_element_status_request *);
static int ch_getelemstatus(struct ch_softc *, int, int, void *,
size_t, int, int);
static int ch_setvoltag(struct ch_softc *,
struct changer_set_voltag_request *);
static int ch_get_params(struct ch_softc *, int);
static void ch_get_quirks(struct ch_softc *,
struct scsipi_inquiry_pattern *);
static void ch_event(struct ch_softc *, u_int);
static int ch_map_element(struct ch_softc *, u_int16_t, int *, int *);

static void ch_voltag_convert_in(const struct changer_volume_tag *,
struct changer_voltag *);
static int ch_voltag_convert_out(const struct changer_voltag *,
struct changer_volume_tag *);

/*
* SCSI changer quirks.
*/
struct chquirk {
struct scsipi_inquiry_pattern cq_match; /* device id pattern */
int cq_settledelay; /* settle delay, in seconds */
};

static const struct chquirk chquirks[] = {
{{T_CHANGER, T_REMOV,
"SPECTRA", "9000", "0200"},
75},
};

static int
chmatch(device_t parent, cfdata_t match,
void *aux)
{
struct scsipibus_attach_args *sa = aux;
int priority;

(void)scsipi_inqmatch(&sa->sa_inqbuf,
(void *)ch_patterns, sizeof(ch_patterns) / sizeof(ch_patterns[0]),
sizeof(ch_patterns[0]), &priority);

return (priority);
}

static void
chattach(device_t parent, device_t self, void *aux)
{
struct ch_softc *sc = device_private(self);
struct scsipibus_attach_args *sa = aux;
struct scsipi_periph *periph = sa->sa_periph;

sc->sc_dev = self;
selinit(&sc->sc_selq);

/* Glue into the SCSI bus */
sc->sc_periph = periph;
periph->periph_dev = sc->sc_dev;
periph->periph_switch = &ch_switch;

printf("\n");

/*
* Find out our device's quirks.
*/
ch_get_quirks(sc, &sa->sa_inqbuf);

/*
* Some changers require a long time to settle out, to do
* tape inventory, for instance.
*/
if (sc->sc_settledelay) {
printf("%s: waiting %d seconds for changer to settle...\n",
device_xname(sc->sc_dev), sc->sc_settledelay);
delay(1000000 * sc->sc_settledelay);
}

/*
* Get information about the device. Note we can't use
* interrupts yet.
*/
if (ch_get_params(sc, XS_CTL_DISCOVERY|XS_CTL_IGNORE_MEDIA_CHANGE))
printf("%s: offline\n", device_xname(sc->sc_dev));
else {
#define PLURAL(c) (c) == 1 ? "" : "s"
printf("%s: %d slot%s, %d drive%s, %d picker%s, %d portal%s\n",
device_xname(sc->sc_dev),
sc->sc_counts[CHET_ST], PLURAL(sc->sc_counts[CHET_ST]),
sc->sc_counts[CHET_DT], PLURAL(sc->sc_counts[CHET_DT]),
sc->sc_counts[CHET_MT], PLURAL(sc->sc_counts[CHET_MT]),
sc->sc_counts[CHET_IE], PLURAL(sc->sc_counts[CHET_IE]));
#undef PLURAL
#ifdef CHANGER_DEBUG
printf("%s: move mask: 0x%x 0x%x 0x%x 0x%x\n",
device_xname(sc->sc_dev),
sc->sc_movemask[CHET_MT], sc->sc_movemask[CHET_ST],
sc->sc_movemask[CHET_IE], sc->sc_movemask[CHET_DT]);
printf("%s: exchange mask: 0x%x 0x%x 0x%x 0x%x\n",
device_xname(sc->sc_dev),
sc->sc_exchangemask[CHET_MT], sc->sc_exchangemask[CHET_ST],
sc->sc_exchangemask[CHET_IE], sc->sc_exchangemask[CHET_DT]);
#endif /* CHANGER_DEBUG */
}

/* Default the current picker. */
sc->sc_picker = sc->sc_firsts[CHET_MT];
}

static int
chopen(dev_t dev, int flags, int fmt, struct lwp *l)
{
struct ch_softc *sc;
struct scsipi_periph *periph;
struct scsipi_adapter *adapt;
int unit, error;

unit = CHUNIT(dev);
sc = device_lookup_private(&ch_cd, unit);
if (sc == NULL)
return (ENXIO);

periph = sc->sc_periph;
adapt = periph->periph_channel->chan_adapter;

/*
* Only allow one open at a time.
*/
if (periph->periph_flags & PERIPH_OPEN)
return (EBUSY);

if ((error = scsipi_adapter_addref(adapt)) != 0)
return (error);

/*
* Make sure the unit is on-line. If a UNIT ATTENTION
* occurs, we will mark that an Init-Element-Status is
* needed in ch_get_params().
*
* We ignore NOT READY in case e.g a magazine isn't actually
* loaded into the changer or a tape isn't in the drive.
*/
error = scsipi_test_unit_ready(periph, XS_CTL_IGNORE_NOT_READY);
if (error)
goto bad;

periph->periph_flags |= PERIPH_OPEN;

/*
* Make sure our parameters are up to date.
*/
if ((error = ch_get_params(sc, 0)) != 0)
goto bad;

return (0);

bad:
scsipi_adapter_delref(adapt);
periph->periph_flags &= ~PERIPH_OPEN;
return (error);
}

static int
chclose(dev_t dev, int flags, int fmt, struct lwp *l)
{
struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
struct scsipi_periph *periph = sc->sc_periph;
struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;

scsipi_wait_drain(periph);

scsipi_adapter_delref(adapt);

sc->sc_events = 0;

periph->periph_flags &= ~PERIPH_OPEN;
return (0);
}

static int
chread(dev_t dev, struct uio *uio, int flags)
{
struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
int error;

if (uio->uio_resid != CHANGER_EVENT_SIZE)
return (EINVAL);

/*
* Read never blocks; if there are no events pending, we just
* return an all-clear bitmask.
*/
error = uiomove(&sc->sc_events, CHANGER_EVENT_SIZE, uio);
if (error == 0)
sc->sc_events = 0;
return (error);
}

static int
chioctl(dev_t dev, u_long cmd, void *data, int flags, struct lwp *l)
{
struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
int error = 0;

/*
* If this command can change the device's state, we must
* have the device open for writing.
*/
switch (cmd) {
case CHIOGPICKER:
case CHIOGPARAMS:
case OCHIOGSTATUS:
break;

default:
if ((flags & FWRITE) == 0)
return (EBADF);
}

switch (cmd) {
case CHIOMOVE:
error = ch_move(sc, (struct changer_move_request *)data);
break;

case CHIOEXCHANGE:
error = ch_exchange(sc,
(struct changer_exchange_request *)data);
break;

case CHIOPOSITION:
error = ch_position(sc,
(struct changer_position_request *)data);
break;

case CHIOGPICKER:
*(int *)data = sc->sc_picker - sc->sc_firsts[CHET_MT];
break;

case CHIOSPICKER:
{
int new_picker = *(int *)data;

if (new_picker > (sc->sc_counts[CHET_MT] - 1))
return (EINVAL);
sc->sc_picker = sc->sc_firsts[CHET_MT] + new_picker;
break;
}

case CHIOGPARAMS:
{
struct changer_params *cp = (struct changer_params *)data;

cp->cp_curpicker = sc->sc_picker - sc->sc_firsts[CHET_MT];
cp->cp_npickers = sc->sc_counts[CHET_MT];
cp->cp_nslots = sc->sc_counts[CHET_ST];
cp->cp_nportals = sc->sc_counts[CHET_IE];
cp->cp_ndrives = sc->sc_counts[CHET_DT];
break;
}

case CHIOIELEM:
error = ch_ielem(sc);
if (error == 0) {
sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
}
break;

case OCHIOGSTATUS:
{
struct ochanger_element_status_request *cesr =
(struct ochanger_element_status_request *)data;

error = ch_ousergetelemstatus(sc, cesr->cesr_type,
cesr->cesr_data);
break;
}

case CHIOGSTATUS:
error = ch_usergetelemstatus(sc,
(struct changer_element_status_request *)data);
break;

case CHIOSVOLTAG:
error = ch_setvoltag(sc,
(struct changer_set_voltag_request *)data);
break;

/* Implement prevent/allow? */

default:
error = scsipi_do_ioctl(sc->sc_periph, dev, cmd, data,
flags, l);
break;
}

return (error);
}

static int
chpoll(dev_t dev, int events, struct lwp *l)
{
struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
int revents;

revents = events & (POLLOUT | POLLWRNORM);

if ((events & (POLLIN | POLLRDNORM)) == 0)
return (revents);

if (sc->sc_events == 0)
revents |= events & (POLLIN | POLLRDNORM);
else
selrecord(l, &sc->sc_selq);

return (revents);
}

static void
filt_chdetach(struct knote *kn)
{
struct ch_softc *sc = kn->kn_hook;

selremove_knote(&sc->sc_selq, kn);
}

static int
filt_chread(struct knote *kn, long hint)
{
struct ch_softc *sc = kn->kn_hook;

if (sc->sc_events == 0)
return (0);
kn->kn_data = CHANGER_EVENT_SIZE;
return (1);
}

static const struct filterops chread_filtops = {
.f_flags = FILTEROP_ISFD,
.f_attach = NULL,
.f_detach = filt_chdetach,
.f_event = filt_chread,
};

static int
chkqfilter(dev_t dev, struct knote *kn)
{
struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));

switch (kn->kn_filter) {
case EVFILT_READ:
kn->kn_fop = &chread_filtops;
kn->kn_hook = sc;
selrecord_knote(&sc->sc_selq, kn);
break;

case EVFILT_WRITE:
kn->kn_fop = &seltrue_filtops;
break;

default:
return (EINVAL);
}

return (0);
}

static int
ch_interpret_sense(struct scsipi_xfer *xs)
{
struct scsipi_periph *periph = xs->xs_periph;
struct scsi_sense_data *sense = &xs->sense.scsi_sense;
struct ch_softc *sc = device_private(periph->periph_dev);
u_int16_t asc_ascq;

/*
* If the periph is already recovering, just do the
* normal error recovering.
*/
if (periph->periph_flags & PERIPH_RECOVERING)
return (EJUSTRETURN);

/*
* If it isn't an extended or extended/deferred error, let
* the generic code handle it.
*/
if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
return (EJUSTRETURN);

/*
* We're only interested in condtions that
* indicate potential inventory violation.
*
* We use ASC/ASCQ codes for this.
*/

asc_ascq = (((u_int16_t) sense->asc) << 8) |
sense->ascq;

switch (asc_ascq) {
case 0x2800:
/* "Not Ready To Ready Transition (Medium May Have Changed)" */
case 0x2900:
/* "Power On, Reset, or Bus Device Reset Occurred" */
sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
/*
* Enqueue an Element-Status-Changed event, and wake up
* any processes waiting for them.
*/
if ((xs->xs_control & XS_CTL_IGNORE_MEDIA_CHANGE) == 0)
ch_event(sc, CHEV_ELEMENT_STATUS_CHANGED);
break;
default:
break;
}

return (EJUSTRETURN);
}

static void
ch_event(struct ch_softc *sc, u_int event)
{

sc->sc_events |= event;
selnotify(&sc->sc_selq, 0, 0);
}

static int
ch_move(struct ch_softc *sc, struct changer_move_request *cm)
{
struct scsi_move_medium cmd;
u_int16_t fromelem, toelem;

/*
* Check arguments.
*/
if ((cm->cm_fromtype > CHET_DT) || (cm->cm_totype > CHET_DT))
return (EINVAL);
if ((cm->cm_fromunit > (sc->sc_counts[cm->cm_fromtype] - 1)) ||
(cm->cm_tounit > (sc->sc_counts[cm->cm_totype] - 1)))
return (ENODEV);

/*
* Check the request against the changer's capabilities.
*/
if ((sc->sc_movemask[cm->cm_fromtype] & (1 << cm->cm_totype)) == 0)
return (ENODEV);

/*
* Calculate the source and destination elements.
*/
fromelem = sc->sc_firsts[cm->cm_fromtype] + cm->cm_fromunit;
toelem = sc->sc_firsts[cm->cm_totype] + cm->cm_tounit;

/*
* Build the SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = MOVE_MEDIUM;
_lto2b(sc->sc_picker, cmd.tea);
_lto2b(fromelem, cmd.src);
_lto2b(toelem, cmd.dst);
if (cm->cm_flags & CM_INVERT)
cmd.flags |= MOVE_MEDIUM_INVERT;

/*
* Send command to changer.
*/
return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
CHRETRIES, CHTIMEOUT, NULL, 0));
}

static int
ch_exchange(struct ch_softc *sc, struct changer_exchange_request *ce)
{
struct scsi_exchange_medium cmd;
u_int16_t src, dst1, dst2;

/*
* Check arguments.
*/
if ((ce->ce_srctype > CHET_DT) || (ce->ce_fdsttype > CHET_DT) ||
(ce->ce_sdsttype > CHET_DT))
return (EINVAL);
if ((ce->ce_srcunit > (sc->sc_counts[ce->ce_srctype] - 1)) ||
(ce->ce_fdstunit > (sc->sc_counts[ce->ce_fdsttype] - 1)) ||
(ce->ce_sdstunit > (sc->sc_counts[ce->ce_sdsttype] - 1)))
return (ENODEV);

/*
* Check the request against the changer's capabilities.
*/
if (((sc->sc_exchangemask[ce->ce_srctype] &
(1 << ce->ce_fdsttype)) == 0) ||
((sc->sc_exchangemask[ce->ce_fdsttype] &
(1 << ce->ce_sdsttype)) == 0))
return (ENODEV);

/*
* Calculate the source and destination elements.
*/
src = sc->sc_firsts[ce->ce_srctype] + ce->ce_srcunit;
dst1 = sc->sc_firsts[ce->ce_fdsttype] + ce->ce_fdstunit;
dst2 = sc->sc_firsts[ce->ce_sdsttype] + ce->ce_sdstunit;

/*
* Build the SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = EXCHANGE_MEDIUM;
_lto2b(sc->sc_picker, cmd.tea);
_lto2b(src, cmd.src);
_lto2b(dst1, cmd.fdst);
_lto2b(dst2, cmd.sdst);
if (ce->ce_flags & CE_INVERT1)
cmd.flags |= EXCHANGE_MEDIUM_INV1;
if (ce->ce_flags & CE_INVERT2)
cmd.flags |= EXCHANGE_MEDIUM_INV2;

/*
* Send command to changer.
*/
return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
CHRETRIES, CHTIMEOUT, NULL, 0));
}

static int
ch_position(struct ch_softc *sc, struct changer_position_request *cp)
{
struct scsi_position_to_element cmd;
u_int16_t dst;

/*
* Check arguments.
*/
if (cp->cp_type > CHET_DT)
return (EINVAL);
if (cp->cp_unit > (sc->sc_counts[cp->cp_type] - 1))
return (ENODEV);

/*
* Calculate the destination element.
*/
dst = sc->sc_firsts[cp->cp_type] + cp->cp_unit;

/*
* Build the SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = POSITION_TO_ELEMENT;
_lto2b(sc->sc_picker, cmd.tea);
_lto2b(dst, cmd.dst);
if (cp->cp_flags & CP_INVERT)
cmd.flags |= POSITION_TO_ELEMENT_INVERT;

/*
* Send command to changer.
*/
return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
CHRETRIES, CHTIMEOUT, NULL, 0));
}

/*
* Perform a READ ELEMENT STATUS on behalf of the user, and return to
* the user only the data the user is interested in. This returns the
* old data format.
*/
static int
ch_ousergetelemstatus(struct ch_softc *sc, int chet, u_int8_t *uptr)
{
struct read_element_status_header *st_hdrp, st_hdr;
struct read_element_status_page_header *pg_hdrp;
struct read_element_status_descriptor *desc;
size_t size, desclen;
void *data;
int avail, i, error = 0;
u_int8_t user_data;

/*
* If there are no elements of the requested type in the changer,
* the request is invalid.
*/
if (sc->sc_counts[chet] == 0)
return (EINVAL);

/*
* Do the request the user wants, but only read the status header.
* This will tell us the amount of storage we must allocate in
* order to read all data.
*/
error = ch_getelemstatus(sc, sc->sc_firsts[chet],
sc->sc_counts[chet], &st_hdr, sizeof(st_hdr), 0, 0);
if (error)
return (error);

size = sizeof(struct read_element_status_header) +
_3btol(st_hdr.nbytes);

/*
* We must have at least room for the status header and
* one page header (since we only ask for one element type
* at a time).
*/
if (size < (sizeof(struct read_element_status_header) +
sizeof(struct read_element_status_page_header)))
return (EIO);

/*
* Allocate the storage and do the request again.
*/
data = malloc(size, M_DEVBUF, M_WAITOK);
error = ch_getelemstatus(sc, sc->sc_firsts[chet],
sc->sc_counts[chet], data, size, 0, 0);
if (error)
goto done;

st_hdrp = (struct read_element_status_header *)data;
pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
sizeof(struct read_element_status_header));
desclen = _2btol(pg_hdrp->edl);

/*
* Fill in the user status array.
*/
avail = _2btol(st_hdrp->count);

if (avail != sc->sc_counts[chet])
printf("%s: warning, READ ELEMENT STATUS avail != count\n",
device_xname(sc->sc_dev));

desc = (struct read_element_status_descriptor *)((u_long)data +
sizeof(struct read_element_status_header) +
sizeof(struct read_element_status_page_header));
for (i = 0; i < avail; ++i) {
user_data = desc->flags1;
error = copyout(&user_data, &uptr[i], avail);
if (error)
break;
desc = (struct read_element_status_descriptor *)((u_long)desc
+ desclen);
}

done:
if (data != NULL)
free(data, M_DEVBUF);
return (error);
}

/*
* Perform a READ ELEMENT STATUS on behalf of the user. This returns
* the new (more complete) data format.
*/
static int
ch_usergetelemstatus(struct ch_softc *sc,
struct changer_element_status_request *cesr)
{
struct scsipi_channel *chan = sc->sc_periph->periph_channel;
struct scsipi_periph *dtperiph;
struct read_element_status_header *st_hdrp, st_hdr;
struct read_element_status_page_header *pg_hdrp;
struct read_element_status_descriptor *desc;
struct changer_volume_tag *avol, *pvol;
size_t size, desclen, stddesclen, offset;
int first, avail, i, error = 0;
void *data;
void *uvendptr;
struct changer_element_status ces;

/*
* Check arguments.
*/
if (cesr->cesr_type > CHET_DT)
return (EINVAL);
if (sc->sc_counts[cesr->cesr_type] == 0)
return (ENODEV);
if (cesr->cesr_unit > (sc->sc_counts[cesr->cesr_type] - 1))
return (ENODEV);
if (cesr->cesr_count >
(sc->sc_counts[cesr->cesr_type] + cesr->cesr_unit))
return (EINVAL);

/*
* Do the request the user wants, but only read the status header.
* This will tell us the amount of storage we must allocate
* in order to read all the data.
*/
error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
cesr->cesr_unit, cesr->cesr_count, &st_hdr, sizeof(st_hdr), 0,
cesr->cesr_flags);
if (error)
return (error);

size = sizeof(struct read_element_status_header) +
_3btol(st_hdr.nbytes);

/*
* We must have at least room for the status header and
* one page header (since we only ask for oen element type
* at a time).
*/
if (size < (sizeof(struct read_element_status_header) +
sizeof(struct read_element_status_page_header)))
return (EIO);

/*
* Allocate the storage and do the request again.
*/
data = malloc(size, M_DEVBUF, M_WAITOK);
error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
cesr->cesr_unit, cesr->cesr_count, data, size, 0,
cesr->cesr_flags);
if (error)
goto done;

st_hdrp = (struct read_element_status_header *)data;
pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
sizeof(struct read_element_status_header));
desclen = _2btol(pg_hdrp->edl);

/*
* Fill in the user status array.
*/
first = _2btol(st_hdrp->fear);
if (first < (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit) ||
first >= (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit +
cesr->cesr_count)) {
error = EIO;
goto done;
}
first -= sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit;

avail = _2btol(st_hdrp->count);
if (avail <= 0 || avail > cesr->cesr_count) {
error = EIO;
goto done;
}

offset = sizeof(struct read_element_status_header) +
sizeof(struct read_element_status_page_header);

for (i = 0; i < cesr->cesr_count; i++) {
memset(&ces, 0, sizeof(ces));
if (i < first || i >= (first + avail)) {
error = copyout(&ces, &cesr->cesr_data[i],
sizeof(ces));
if (error)
goto done;
}

desc = (struct read_element_status_descriptor *)
((char *)data + offset);
stddesclen = sizeof(struct read_element_status_descriptor);
offset += desclen;

ces.ces_flags = CESTATUS_STATUS_VALID;

/*
* The SCSI flags conveniently map directly to the
* chio API flags.
*/
ces.ces_flags |= (desc->flags1 & 0x3f);

ces.ces_asc = desc->sense_code;
ces.ces_ascq = desc->sense_qual;

/*
* For Data Transport elemenets, get the SCSI ID and LUN,
* and attempt to map them to a device name if they're
* on the same SCSI bus.
*/
if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_IDVALID) {
ces.ces_target = desc->dt_scsi_addr;
ces.ces_flags |= CESTATUS_TARGET_VALID;
}
if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_LUVALID) {
ces.ces_lun = desc->dt_scsi_flags &
READ_ELEMENT_STATUS_DT_LUNMASK;
ces.ces_flags |= CESTATUS_LUN_VALID;
}
if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_NOTBUS)
ces.ces_flags |= CESTATUS_NOTBUS;
else if ((ces.ces_flags &
(CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) ==
(CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) {
if (ces.ces_target < chan->chan_ntargets &&
ces.ces_lun < chan->chan_nluns &&
(dtperiph = scsipi_lookup_periph(chan,
ces.ces_target, ces.ces_lun)) != NULL &&
dtperiph->periph_dev != NULL) {
strlcpy(ces.ces_xname,
device_xname(dtperiph->periph_dev),
sizeof(ces.ces_xname));
ces.ces_flags |= CESTATUS_XNAME_VALID;
}
}

if (desc->flags2 & READ_ELEMENT_STATUS_INVERT)
ces.ces_flags |= CESTATUS_INVERTED;

if (desc->flags2 & READ_ELEMENT_STATUS_SVALID) {
if (ch_map_element(sc, _2btol(desc->ssea),
&ces.ces_from_type, &ces.ces_from_unit))
ces.ces_flags |= CESTATUS_FROM_VALID;
}

/*
* Extract volume tag information.
*/
switch (pg_hdrp->flags &
(READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG)) {
case (READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG):
pvol = (struct changer_volume_tag *)(desc + 1);
avol = pvol + 1;
break;

case READ_ELEMENT_STATUS_PVOLTAG:
pvol = (struct changer_volume_tag *)(desc + 1);
avol = NULL;
break;

case READ_ELEMENT_STATUS_AVOLTAG:
pvol = NULL;
avol = (struct changer_volume_tag *)(desc + 1);
break;

default:
avol = pvol = NULL;
break;
}

if (pvol != NULL) {
ch_voltag_convert_in(pvol, &ces.ces_pvoltag);
ces.ces_flags |= CESTATUS_PVOL_VALID;
stddesclen += sizeof(struct changer_volume_tag);
}
if (avol != NULL) {
ch_voltag_convert_in(avol, &ces.ces_avoltag);
ces.ces_flags |= CESTATUS_AVOL_VALID;
stddesclen += sizeof(struct changer_volume_tag);
}

/*
* Compute vendor-specific length. Note the 4 reserved
* bytes between the volume tags and the vendor-specific
* data. Copy it out of the user wants it.
*/
stddesclen += 4;
if (desclen > stddesclen)
ces.ces_vendor_len = desclen - stddesclen;

if (ces.ces_vendor_len != 0 && cesr->cesr_vendor_data != NULL) {
error = copyin(&cesr->cesr_vendor_data[i], &uvendptr,
sizeof(uvendptr));
if (error)
goto done;
error = copyout((void *)((u_long)desc + stddesclen),
uvendptr, ces.ces_vendor_len);
if (error)
goto done;
}

/*
* Now copy out the status descriptor we've constructed.
*/
error = copyout(&ces, &cesr->cesr_data[i], sizeof(ces));
if (error)
goto done;
}

done:
if (data != NULL)
free(data, M_DEVBUF);
return (error);
}

static int
ch_getelemstatus(struct ch_softc *sc, int first, int count, void *data,
size_t datalen, int scsiflags, int flags)
{
struct scsi_read_element_status cmd;

/*
* Build SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = READ_ELEMENT_STATUS;
cmd.byte2 = ELEMENT_TYPE_ALL;
if (flags & CESR_VOLTAGS)
cmd.byte2 |= READ_ELEMENT_STATUS_VOLTAG;
_lto2b(first, cmd.sea);
_lto2b(count, cmd.count);
_lto3b(datalen, cmd.len);

/*
* Send command to changer.
*/
return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
(void *)data, datalen,
CHRETRIES, CHTIMEOUT, NULL, scsiflags | XS_CTL_DATA_IN));
}

static int
ch_setvoltag(struct ch_softc *sc, struct changer_set_voltag_request *csvr)
{
struct scsi_send_volume_tag cmd;
struct changer_volume_tag voltag;
void *data = NULL;
size_t datalen = 0;
int error;
u_int16_t dst;

/*
* Check arguments.
*/
if (csvr->csvr_type > CHET_DT)
return (EINVAL);
if (csvr->csvr_unit > (sc->sc_counts[csvr->csvr_type] - 1))
return (ENODEV);

dst = sc->sc_firsts[csvr->csvr_type] + csvr->csvr_unit;

/*
* Build the SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = SEND_VOLUME_TAG;
_lto2b(dst, cmd.eaddr);

#define ALTERNATE (csvr->csvr_flags & CSVR_ALTERNATE)

switch (csvr->csvr_flags & CSVR_MODE_MASK) {
case CSVR_MODE_SET:
cmd.sac = ALTERNATE ? SAC_ASSERT_ALT : SAC_ASSERT_PRIMARY;
break;

case CSVR_MODE_REPLACE:
cmd.sac = ALTERNATE ? SAC_REPLACE_ALT : SAC_REPLACE_PRIMARY;
break;

case CSVR_MODE_CLEAR:
cmd.sac = ALTERNATE ? SAC_UNDEFINED_ALT : SAC_UNDEFINED_PRIMARY;
break;

default:
return (EINVAL);
}

#undef ALTERNATE

if (cmd.sac < SAC_UNDEFINED_PRIMARY) {
error = ch_voltag_convert_out(&csvr->csvr_voltag, &voltag);
if (error)
return (error);
data = &voltag;
datalen = sizeof(voltag);
_lto2b(datalen, cmd.length);
}

/*
* Send command to changer.
*/
return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
(void *)data, datalen, CHRETRIES, CHTIMEOUT, NULL,
datalen ? XS_CTL_DATA_OUT : 0));
}

static int
ch_ielem(struct ch_softc *sc)
{
int tmo;
struct scsi_initialize_element_status cmd;

/*
* Build SCSI command.
*/
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = INITIALIZE_ELEMENT_STATUS;

/*
* Send command to changer.
*
* The problem is, how long to allow for the command?
* It can take a *really* long time, and also depends
* on unknowable factors such as whether there are
* *almost* readable labels on tapes that a barcode
* reader is trying to decipher.
*
* I'm going to make this long enough to allow 5 minutes
* per element plus an initial 10 minute wait.
*/
tmo = sc->sc_counts[CHET_MT] +
sc->sc_counts[CHET_ST] +
sc->sc_counts[CHET_IE] +
sc->sc_counts[CHET_DT];
tmo *= 5 * 60 * 1000;
tmo += (10 * 60 * 1000);

return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
CHRETRIES, tmo, NULL, XS_CTL_IGNORE_ILLEGAL_REQUEST));
}

/*
* Ask the device about itself and fill in the parameters in our
* softc.
*/
static int
ch_get_params(struct ch_softc *sc, int scsiflags)
{
struct scsi_mode_sense_data {
struct scsi_mode_parameter_header_6 header;
union {
struct page_element_address_assignment ea;
struct page_transport_geometry_parameters tg;
struct page_device_capabilities cap;
} pages;
} sense_data;
int error, from;
u_int8_t *moves, *exchanges;

/*
* Grab info from the element address assignment page.
*/
memset(&sense_data, 0, sizeof(sense_data));
error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1d,
&sense_data.header, sizeof(sense_data),
scsiflags, CHRETRIES, 6000);
if (error) {
aprint_error_dev(sc->sc_dev, "could not sense element address page\n");
return (error);
}

sc->sc_firsts[CHET_MT] = _2btol(sense_data.pages.ea.mtea);
sc->sc_counts[CHET_MT] = _2btol(sense_data.pages.ea.nmte);
sc->sc_firsts[CHET_ST] = _2btol(sense_data.pages.ea.fsea);
sc->sc_counts[CHET_ST] = _2btol(sense_data.pages.ea.nse);
sc->sc_firsts[CHET_IE] = _2btol(sense_data.pages.ea.fieea);
sc->sc_counts[CHET_IE] = _2btol(sense_data.pages.ea.niee);
sc->sc_firsts[CHET_DT] = _2btol(sense_data.pages.ea.fdtea);
sc->sc_counts[CHET_DT] = _2btol(sense_data.pages.ea.ndte);

/* XXX ask for transport geometry page XXX */

/*
* Grab info from the capabilities page.
*/
memset(&sense_data, 0, sizeof(sense_data));
/*
* XXX: Note: not all changers can deal with disabled block descriptors
*/
error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1f,
&sense_data.header, sizeof(sense_data),
scsiflags, CHRETRIES, 6000);
if (error) {
aprint_error_dev(sc->sc_dev, "could not sense capabilities page\n");
return (error);
}

memset(sc->sc_movemask, 0, sizeof(sc->sc_movemask));
memset(sc->sc_exchangemask, 0, sizeof(sc->sc_exchangemask));
moves = &sense_data.pages.cap.move_from_mt;
exchanges = &sense_data.pages.cap.exchange_with_mt;
for (from = CHET_MT; from <= CHET_DT; ++from) {
sc->sc_movemask[from] = moves[from];
sc->sc_exchangemask[from] = exchanges[from];
}

#ifdef CH_AUTOMATIC_IELEM_POLICY
/*
* If we need to do an Init-Element-Status,
* do that now that we know what's in the changer.
*/
if ((scsiflags & XS_CTL_IGNORE_MEDIA_CHANGE) == 0) {
if ((sc->sc_periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
error = ch_ielem(sc);
if (error == 0)
sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
else
sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
}
#endif
return (error);
}

static void
ch_get_quirks(struct ch_softc *sc, struct scsipi_inquiry_pattern *inqbuf)
{
const struct chquirk *match;
int priority;

sc->sc_settledelay = 0;

match = scsipi_inqmatch(inqbuf, chquirks,
sizeof(chquirks) / sizeof(chquirks[0]),
sizeof(chquirks[0]), &priority);
if (priority != 0)
sc->sc_settledelay = match->cq_settledelay;
}

static int
ch_map_element(struct ch_softc *sc, u_int16_t elem, int *typep, int *unitp)
{
int chet;

for (chet = CHET_MT; chet <= CHET_DT; chet++) {
if (elem >= sc->sc_firsts[chet] &&
elem < (sc->sc_firsts[chet] + sc->sc_counts[chet])) {
*typep = chet;
*unitp = elem - sc->sc_firsts[chet];
return (1);
}
}
return (0);
}

static void
ch_voltag_convert_in(const struct changer_volume_tag *sv,
struct changer_voltag *cv)
{
int i;

memset(cv, 0, sizeof(struct changer_voltag));

/*
* Copy the volume tag string from the SCSI representation.
* Per the SCSI-2 spec, we stop at the first blank character.
*/
for (i = 0; i < sizeof(sv->volid); i++) {
if (sv->volid[i] == ' ')
break;
cv->cv_tag[i] = sv->volid[i];
}
cv->cv_tag[i] = '\0';

cv->cv_serial = _2btol(sv->volseq);
}

static int
ch_voltag_convert_out(const struct changer_voltag *cv,
struct changer_volume_tag *sv)
{
int i;

memset(sv, ' ', sizeof(struct changer_volume_tag));

for (i = 0; i < sizeof(sv->volid); i++) {
if (cv->cv_tag[i] == '\0')
break;
/*
* Limit the character set to what is suggested in
* the SCSI-2 spec.
*/
if ((cv->cv_tag[i] < '0' || cv->cv_tag[i] > '9') &&
(cv->cv_tag[i] < 'A' || cv->cv_tag[i] > 'Z') &&
(cv->cv_tag[i] != '_'))
return (EINVAL);
sv->volid[i] = cv->cv_tag[i];
}

_lto2b(cv->cv_serial, sv->volseq);

return (0);
}