Sync CAM with FreeBSD using lockmgr locks instead of mutexes.

[dragonfly.git] / sys / bus / cam / scsi / scsi_cd.c

/*
 * Copyright (c) 1997 Justin T. Gibbs.
 * Copyright (c) 1997, 1998, 1999, 2000, 2001, 2003, 2003 Kenneth D. Merry.
 * 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. 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 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 AUTHOR 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.
 *
 * $FreeBSD: src/sys/cam/scsi/scsi_cd.c,v 1.31.2.16 2003/10/21 22:26:11 thomas Exp $
 * $DragonFly: src/sys/bus/cam/scsi/scsi_cd.c,v 1.42 2008/05/18 20:30:19 pavalos Exp $
 */
/*
 * Portions of this driver taken from the original FreeBSD cd driver.
 * Written by Julian Elischer (julian@tfs.com)
 * for TRW Financial Systems for use under the MACH(2.5) operating system.
 *
 * TRW Financial Systems, in accordance with their agreement with Carnegie
 * Mellon University, makes this software available to CMU to distribute
 * or use in any manner that they see fit as long as this message is kept with
 * the software. For this reason TFS also grants any other persons or
 * organisations permission to use or modify this software.
 *
 * TFS supplies this software to be publicly redistributed
 * on the understanding that TFS is not responsible for the correct
 * functioning of this software in any circumstances.
 *
 * Ported to run under 386BSD by Julian Elischer (julian@tfs.com) Sept 1992
 *
 *      from: cd.c,v 1.83 1997/05/04 15:24:22 joerg Exp $
 */

#include "opt_cd.h"

#include <sys/param.h>
#include <sys/bootmaj.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/disk.h>
#include <sys/dtype.h>
#include <sys/malloc.h>
#include <sys/cdio.h>
#include <sys/cdrio.h>
#include <sys/dvdio.h>
#include <sys/devicestat.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <sys/proc.h>
#include <sys/buf2.h>
#include <sys/thread2.h>

#include "../cam.h"
#include "../cam_ccb.h"
#include "../cam_extend.h"
#include "../cam_periph.h"
#include "../cam_xpt_periph.h"
#include "../cam_queue.h"
#include "../cam_sim.h"

#include "scsi_message.h"
#include "scsi_da.h"
#include "scsi_cd.h"

#define LEADOUT         0xaa            /* leadout toc entry */

struct cd_params {
        u_int32_t blksize;
        u_long    disksize;
};

typedef enum {
        CD_Q_NONE               = 0x00,
        CD_Q_NO_TOUCH           = 0x01,
        CD_Q_BCD_TRACKS         = 0x02,
        CD_Q_NO_CHANGER         = 0x04,
        CD_Q_CHANGER            = 0x08,
        CD_Q_10_BYTE_ONLY       = 0x10
} cd_quirks;

typedef enum {
        CD_FLAG_INVALID         = 0x0001,
        CD_FLAG_NEW_DISC        = 0x0002,
        CD_FLAG_DISC_LOCKED     = 0x0004,
        CD_FLAG_DISC_REMOVABLE  = 0x0008,
        CD_FLAG_TAGGED_QUEUING  = 0x0010,
        CD_FLAG_CHANGER         = 0x0040,
        CD_FLAG_ACTIVE          = 0x0080,
        CD_FLAG_SCHED_ON_COMP   = 0x0100,
        CD_FLAG_RETRY_UA        = 0x0200,
        CD_FLAG_VALID_MEDIA     = 0x0400,
        CD_FLAG_VALID_TOC       = 0x0800,
        CD_FLAG_SCTX_INIT       = 0x1000,
        CD_FLAG_OPEN            = 0x2000
} cd_flags;

typedef enum {
        CD_CCB_PROBE            = 0x01,
        CD_CCB_BUFFER_IO        = 0x02,
        CD_CCB_WAITING          = 0x03,
        CD_CCB_TYPE_MASK        = 0x0F,
        CD_CCB_RETRY_UA         = 0x10
} cd_ccb_state;

typedef enum {
        CHANGER_TIMEOUT_SCHED           = 0x01,
        CHANGER_SHORT_TMOUT_SCHED       = 0x02,
        CHANGER_MANUAL_CALL             = 0x04,
        CHANGER_NEED_TIMEOUT            = 0x08
} cd_changer_flags;

#define ccb_state ppriv_field0
#define ccb_bio ppriv_ptr1

struct cd_tocdata {
        struct ioc_toc_header header;
        struct cd_toc_entry entries[100];
};

struct cd_toc_single {
        struct ioc_toc_header header;
        struct cd_toc_entry entry;
};

typedef enum {
        CD_STATE_PROBE,
        CD_STATE_NORMAL
} cd_state;

struct cd_softc {
        cam_pinfo               pinfo;
        cd_state                state;
        volatile cd_flags       flags;
        struct bio_queue_head   bio_queue;
        LIST_HEAD(, ccb_hdr)    pending_ccbs;
        struct cd_params        params;
        struct disk             disk;
        union ccb               saved_ccb;
        cd_quirks               quirks;
        struct devstat          device_stats;
        STAILQ_ENTRY(cd_softc)  changer_links;
        struct cdchanger        *changer;
        int                     bufs_left;
        struct cam_periph       *periph;
        int                     minimum_command_size;
        int                     outstanding_cmds;
        struct task             sysctl_task;
        struct sysctl_ctx_list  sysctl_ctx;
        struct sysctl_oid       *sysctl_tree;
        STAILQ_HEAD(, cd_mode_params)   mode_queue;
        struct cd_tocdata       toc;
};

struct cd_page_sizes {
        int page;
        int page_size;
};

static struct cd_page_sizes cd_page_size_table[] =
{
        { AUDIO_PAGE, sizeof(struct cd_audio_page)}
};

struct cd_quirk_entry {
        struct scsi_inquiry_pattern inq_pat;
        cd_quirks quirks;
};

/*
 * The changer quirk entries aren't strictly necessary.  Basically, what
 * they do is tell cdregister() up front that a device is a changer.
 * Otherwise, it will figure that fact out once it sees a LUN on the device
 * that is greater than 0.  If it is known up front that a device is a changer,
 * all I/O to the device will go through the changer scheduling routines, as
 * opposed to the "normal" CD code.
 *
 * NOTE ON 10_BYTE_ONLY quirks:  Any 10_BYTE_ONLY quirks MUST be because
 * your device hangs when it gets a 10 byte command.  Adding a quirk just
 * to get rid of the informative diagnostic message is not acceptable.  All
 * 10_BYTE_ONLY quirks must be documented in full in a PR (which should be
 * referenced in a comment along with the quirk) , and must be approved by
 * ken@FreeBSD.org.  Any quirks added that don't adhere to this policy may
 * be removed until the submitter can explain why they are needed.
 * 10_BYTE_ONLY quirks will be removed (as they will no longer be necessary)
 * when the CAM_NEW_TRAN_CODE work is done.
 */
static struct cd_quirk_entry cd_quirk_table[] =
{
        {
                { T_CDROM, SIP_MEDIA_REMOVABLE, "NRC", "MBR-7", "*"},
                 /*quirks*/ CD_Q_CHANGER
        },
        {
                { T_CDROM, SIP_MEDIA_REMOVABLE, "PIONEER", "CD-ROM DRM*",
                  "*"}, /* quirks */ CD_Q_CHANGER
        },
        {
                { T_CDROM, SIP_MEDIA_REMOVABLE, "NAKAMICH", "MJ-*", "*"},
                 /* quirks */ CD_Q_CHANGER
        },
        {
                { T_CDROM, SIP_MEDIA_REMOVABLE, "CHINON", "CD-ROM CDS-535","*"},
                /* quirks */ CD_Q_BCD_TRACKS
        }
};

static  d_open_t        cdopen;
static  d_close_t       cdclose;
static  d_ioctl_t       cdioctl;
static  d_strategy_t    cdstrategy;

static  periph_init_t   cdinit;
static  periph_ctor_t   cdregister;
static  periph_dtor_t   cdcleanup;
static  periph_start_t  cdstart;
static  periph_oninv_t  cdoninvalidate;
static  void            cdasync(void *callback_arg, u_int32_t code,
                                struct cam_path *path, void *arg);
static  int             cdcmdsizesysctl(SYSCTL_HANDLER_ARGS);
static  void            cdshorttimeout(void *arg);
static  void            cdschedule(struct cam_periph *periph, int priority);
static  void            cdrunchangerqueue(void *arg);
static  void            cdchangerschedule(struct cd_softc *softc);
static  int             cdrunccb(union ccb *ccb,
                                 int (*error_routine)(union ccb *ccb,
                                                      u_int32_t cam_flags,
                                                      u_int32_t sense_flags),
                                 u_int32_t cam_flags, u_int32_t sense_flags);
static union    ccb     *cdgetccb(struct cam_periph *periph,
                                  u_int32_t priority);
static  void            cddone(struct cam_periph *periph,
                               union ccb *start_ccb);
static  int             cderror(union ccb *ccb, u_int32_t cam_flags,
                                u_int32_t sense_flags);
static  union cd_pages  *cdgetpage(struct cd_mode_params *mode_params);
static  int             cdgetpagesize(int page_num);
static  void            cdprevent(struct cam_periph *periph, int action);
static  int             cdcheckmedia(struct cam_periph *periph);
static  int             cdsize(struct cam_periph *periph, u_int32_t *size);
static  int             cd6byteworkaround(union ccb *ccb);
static  int             cdreadtoc(struct cam_periph *periph, u_int32_t mode, 
                                  u_int32_t start, u_int8_t *data, 
                                  u_int32_t len, u_int32_t sense_flags);
static  int             cdgetmode(struct cam_periph *periph, 
                                  struct cd_mode_params *data, u_int32_t page);
static  int             cdsetmode(struct cam_periph *periph,
                                  struct cd_mode_params *data);
static  int             cdplay(struct cam_periph *periph, u_int32_t blk, 
                               u_int32_t len);
static  int             cdreadsubchannel(struct cam_periph *periph, 
                                         u_int32_t mode, u_int32_t format, 
                                         int track, 
                                         struct cd_sub_channel_info *data, 
                                         u_int32_t len);
static  int             cdplaymsf(struct cam_periph *periph, u_int32_t startm, 
                                  u_int32_t starts, u_int32_t startf, 
                                  u_int32_t endm, u_int32_t ends, 
                                  u_int32_t endf);
static  int             cdplaytracks(struct cam_periph *periph, 
                                     u_int32_t strack, u_int32_t sindex,
                                     u_int32_t etrack, u_int32_t eindex);
static  int             cdpause(struct cam_periph *periph, u_int32_t go);
static  int             cdstopunit(struct cam_periph *periph, u_int32_t eject);
static  int             cdstartunit(struct cam_periph *periph, int load);
static  int             cdsetspeed(struct cam_periph *periph,
                                   u_int32_t rdspeed, u_int32_t wrspeed);
static  int             cdreportkey(struct cam_periph *periph,
                                    struct dvd_authinfo *authinfo);
static  int             cdsendkey(struct cam_periph *periph,
                                  struct dvd_authinfo *authinfo);
static  int             cdreaddvdstructure(struct cam_periph *periph,
                                           struct dvd_struct *dvdstruct);

static struct periph_driver cddriver =
{
        cdinit, "cd",
        TAILQ_HEAD_INITIALIZER(cddriver.units), /* generation */ 0
};

PERIPHDRIVER_DECLARE(cd, cddriver);

static struct dev_ops cd_ops = {
        { "cd", SCSICD_CDEV_MAJOR, D_DISK },
        .d_open = cdopen,
        .d_close = cdclose,
        .d_read = physread,
        .d_write = physwrite,
        .d_ioctl = cdioctl,
        .d_strategy = cdstrategy
};

static struct extend_array *cdperiphs;

#ifndef CHANGER_MIN_BUSY_SECONDS
#define CHANGER_MIN_BUSY_SECONDS        5
#endif
#ifndef CHANGER_MAX_BUSY_SECONDS
#define CHANGER_MAX_BUSY_SECONDS        15
#endif

static int changer_min_busy_seconds = CHANGER_MIN_BUSY_SECONDS;
static int changer_max_busy_seconds = CHANGER_MAX_BUSY_SECONDS;

SYSCTL_NODE(_kern_cam, OID_AUTO, cd, CTLFLAG_RD, 0, "CAM CDROM driver");
SYSCTL_NODE(_kern_cam_cd, OID_AUTO, changer, CTLFLAG_RD, 0, "CD Changer");
SYSCTL_INT(_kern_cam_cd_changer, OID_AUTO, min_busy_seconds, CTLFLAG_RW,
           &changer_min_busy_seconds, 0, "Minimum changer scheduling quantum");
TUNABLE_INT("kern.cam.cd.changer.min_busy_seconds", &changer_min_busy_seconds);
SYSCTL_INT(_kern_cam_cd_changer, OID_AUTO, max_busy_seconds, CTLFLAG_RW,
           &changer_max_busy_seconds, 0, "Maximum changer scheduling quantum");
TUNABLE_INT("kern.cam.cd.changer.max_busy_seconds", &changer_max_busy_seconds);

struct cdchanger {
        path_id_t                        path_id;
        target_id_t                      target_id;
        int                              num_devices;
        struct camq                      devq;
        struct timeval                   start_time;
        struct cd_softc                  *cur_device;
        struct callout                   short_handle;
        struct callout                   long_handle;
        volatile cd_changer_flags        flags;
        STAILQ_ENTRY(cdchanger)          changer_links;
        STAILQ_HEAD(chdevlist, cd_softc) chluns;
};

static struct lock changerq_lock;
static STAILQ_HEAD(changerlist, cdchanger) changerq;
static int num_changers;

MALLOC_DEFINE(M_SCSICD, "scsi_cd", "scsi_cd buffers");

static void
cdinit(void)
{
        cam_status status;

        lockinit(&changerq_lock, "cdchangerq", 0, LK_CANRECURSE);
        STAILQ_INIT(&changerq);

        /*
         * Create our extend array for storing the devices we attach to.
         */
        cdperiphs = cam_extend_new();
        if (cdperiphs == NULL) {
                kprintf("cd: Failed to alloc extend array!\n");
                return;
        }

        /*
         * Install a global async callback.  This callback will
         * receive async callbacks like "new device found".
         */
        status = xpt_register_async(AC_FOUND_DEVICE, cdasync, NULL, NULL);

        if (status != CAM_REQ_CMP) {
                kprintf("cd: Failed to attach master async callback "
                       "due to status 0x%x!\n", status);
        }
}

static void
cdoninvalidate(struct cam_periph *periph)
{
        struct cd_softc *softc;
        struct buf *q_bp;
        struct bio *q_bio;

        softc = (struct cd_softc *)periph->softc;

        /*
         * De-register any async callbacks.
         */
        xpt_register_async(0, cdasync, periph, periph->path);

        softc->flags |= CD_FLAG_INVALID;

        /*
         * Return all queued I/O with ENXIO.
         * XXX Handle any transactions queued to the card
         *     with XPT_ABORT_CCB.
         */
        while ((q_bio = bioq_first(&softc->bio_queue)) != NULL){
                bioq_remove(&softc->bio_queue, q_bio);
                q_bp = q_bio->bio_buf;
                q_bp->b_resid = q_bp->b_bcount;
                q_bp->b_error = ENXIO;
                q_bp->b_flags |= B_ERROR;
                biodone(q_bio);
        }

        /*
         * If this device is part of a changer, and it was scheduled
         * to run, remove it from the run queue since we just nuked
         * all of its scheduled I/O.
         */
        if ((softc->flags & CD_FLAG_CHANGER)
         && (softc->pinfo.index != CAM_UNQUEUED_INDEX))
                camq_remove(&softc->changer->devq, softc->pinfo.index);

        xpt_print(periph->path, "lost device\n");
}

static void
cdcleanup(struct cam_periph *periph)
{
        struct cd_softc *softc;

        softc = (struct cd_softc *)periph->softc;

        xpt_print(periph->path, "removing device entry\n");

        if ((softc->flags & CD_FLAG_SCTX_INIT) != 0
            && sysctl_ctx_free(&softc->sysctl_ctx) != 0) {
                xpt_print(periph->path, "can't remove sysctl context\n");
        }

        /*
         * In the queued, non-active case, the device in question
         * has already been removed from the changer run queue.  Since this
         * device is active, we need to de-activate it, and schedule
         * another device to run.  (if there is another one to run)
         */
        if ((softc->flags & CD_FLAG_CHANGER)
         && (softc->flags & CD_FLAG_ACTIVE)) {

                /*
                 * The purpose of the short timeout is soley to determine
                 * whether the current device has finished or not.  Well,
                 * since we're removing the active device, we know that it
                 * is finished.  So, get rid of the short timeout.
                 * Otherwise, if we're in the time period before the short
                 * timeout fires, and there are no other devices in the
                 * queue to run, there won't be any other device put in the
                 * active slot.  i.e., when we call cdrunchangerqueue()
                 * below, it won't do anything.  Then, when the short
                 * timeout fires, it'll look at the "current device", which
                 * we are free below, and possibly panic the kernel on a
                 * bogus pointer reference.
                 *
                 * The long timeout doesn't really matter, since we
                 * decrement the qfrozen_cnt to indicate that there is
                 * nothing in the active slot now.  Therefore, there won't
                 * be any bogus pointer references there.
                 */
                if (softc->changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
                        callout_stop(&softc->changer->short_handle);
                        softc->changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
                }
                softc->changer->devq.qfrozen_cnt--;
                softc->changer->flags |= CHANGER_MANUAL_CALL;
                cdrunchangerqueue(softc->changer);
        }

        /*
         * If we're removing the last device on the changer, go ahead and
         * remove the changer device structure.
         */
        if ((softc->flags & CD_FLAG_CHANGER)
         && (--softc->changer->num_devices == 0)) {

                /*
                 * Theoretically, there shouldn't be any timeouts left, but
                 * I'm not completely sure that that will be the case.  So,
                 * it won't hurt to check and see if there are any left.
                 */
                if (softc->changer->flags & CHANGER_TIMEOUT_SCHED) {
                        callout_stop(&softc->changer->long_handle);
                        softc->changer->flags &= ~CHANGER_TIMEOUT_SCHED;
                }

                if (softc->changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
                        callout_stop(&softc->changer->short_handle);
                        softc->changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
                }

                lockmgr(&changerq_lock, LK_EXCLUSIVE);
                STAILQ_REMOVE(&changerq, softc->changer, cdchanger,
                              changer_links);
                num_changers--;
                lockmgr(&changerq_lock, LK_RELEASE);
                xpt_print(periph->path, "removing changer entry\n");
                kfree(softc->changer, M_DEVBUF);
        }
        devstat_remove_entry(&softc->device_stats);
        cam_extend_release(cdperiphs, periph->unit_number);
        if (softc->disk.d_rawdev) {
                cam_periph_unlock(periph);
                disk_destroy(&softc->disk);
                cam_periph_lock(periph);
        }
        kfree(softc, M_DEVBUF);
}

static void
cdasync(void *callback_arg, u_int32_t code,
        struct cam_path *path, void *arg)
{
        struct cam_periph *periph;

        periph = (struct cam_periph *)callback_arg;
        switch (code) {
        case AC_FOUND_DEVICE:
        {
                struct ccb_getdev *cgd;
                cam_status status;

                cgd = (struct ccb_getdev *)arg;
                if (cgd == NULL)
                        break;

                if (SID_TYPE(&cgd->inq_data) != T_CDROM
                    && SID_TYPE(&cgd->inq_data) != T_WORM)
                        break;

                /*
                 * Allocate a peripheral instance for
                 * this device and start the probe
                 * process.
                 */
                status = cam_periph_alloc(cdregister, cdoninvalidate,
                                          cdcleanup, cdstart,
                                          "cd", CAM_PERIPH_BIO,
                                          cgd->ccb_h.path, cdasync,
                                          AC_FOUND_DEVICE, cgd);

                if (status != CAM_REQ_CMP
                 && status != CAM_REQ_INPROG)
                        kprintf("cdasync: Unable to attach new device "
                               "due to status 0x%x\n", status);

                break;
        }
        case AC_SENT_BDR:
        case AC_BUS_RESET:
        {
                struct cd_softc *softc;
                struct ccb_hdr *ccbh;

                softc = (struct cd_softc *)periph->softc;
                /*
                 * Don't fail on the expected unit attention
                 * that will occur.
                 */
                softc->flags |= CD_FLAG_RETRY_UA;
                LIST_FOREACH(ccbh, &softc->pending_ccbs, periph_links.le)
                        ccbh->ccb_state |= CD_CCB_RETRY_UA;
                /* FALLTHROUGH */
        }
        default:
                cam_periph_async(periph, code, path, arg);
                break;
        }
}

static void
cdsysctlinit(void *context, int pending)
{
        struct cam_periph *periph;
        struct cd_softc *softc;
        char tmpstr[80], tmpstr2[80];

        periph = (struct cam_periph *)context;
        if (cam_periph_acquire(periph) != CAM_REQ_CMP)
                return;

        softc = (struct cd_softc *)periph->softc;
        ksnprintf(tmpstr, sizeof(tmpstr), "CAM CD unit %d", periph->unit_number);
        ksnprintf(tmpstr2, sizeof(tmpstr2), "%d", periph->unit_number);

        sysctl_ctx_init(&softc->sysctl_ctx);
        softc->flags |= CD_FLAG_SCTX_INIT;
        softc->sysctl_tree = SYSCTL_ADD_NODE(&softc->sysctl_ctx,
        SYSCTL_STATIC_CHILDREN(_kern_cam_cd), OID_AUTO,
        tmpstr2, CTLFLAG_RD, 0, tmpstr);

        if (softc->sysctl_tree == NULL) {
                kprintf("cdsysctlinit: unable to allocate sysctl tree\n");
                cam_periph_release(periph);
                return;
        }

        /*
         * Now register the sysctl handler, so the user can the value on
         * the fly.
         */
        SYSCTL_ADD_PROC(&softc->sysctl_ctx,SYSCTL_CHILDREN(softc->sysctl_tree),
                        OID_AUTO, "minimum_cmd_size", CTLTYPE_INT | CTLFLAG_RW,
                        &softc->minimum_command_size, 0, cdcmdsizesysctl, "I",
                        "Minimum CDB size");

        cam_periph_release(periph);
}

/*
 * We have a handler function for this so we can check the values when the
 * user sets them, instead of every time we look at them.
 */
static int
cdcmdsizesysctl(SYSCTL_HANDLER_ARGS)
{
        int error, value;

        value = *(int *)arg1;

        error = sysctl_handle_int(oidp, &value, 0, req);

        if ((error != 0) || (req->newptr == NULL))
                return (error);

        /*
         * The only real values we can have here are 6 or 10.  I don't
         * really forsee having 12 be an option at any time in the future.
         * So if the user sets something less than or equal to 6, we'll set
         * it to 6.  If he sets something greater than 6, we'll set it to 10.
         *
         * I suppose we could just return an error here for the wrong values,
         * but I don't think it's necessary to do so, as long as we can
         * determine the user's intent without too much trouble.
         */
        if (value < 6)
                value = 6;
        else if (value > 6)
                value = 10;

        *(int *)arg1 = value;

        return (0);
}


static cam_status
cdregister(struct cam_periph *periph, void *arg)
{
        struct cd_softc *softc;
        struct ccb_pathinq cpi;
        struct ccb_getdev *cgd;
        char tmpstr[80];
        caddr_t match;

        cgd = (struct ccb_getdev *)arg;
        if (periph == NULL) {
                kprintf("cdregister: periph was NULL!!\n");
                return(CAM_REQ_CMP_ERR);
        }
        if (cgd == NULL) {
                kprintf("cdregister: no getdev CCB, can't register device\n");
                return(CAM_REQ_CMP_ERR);
        }

        softc = kmalloc(sizeof(*softc), M_DEVBUF, M_INTWAIT | M_ZERO);
        LIST_INIT(&softc->pending_ccbs);
        STAILQ_INIT(&softc->mode_queue);
        softc->state = CD_STATE_PROBE;
        bioq_init(&softc->bio_queue);
        if (SID_IS_REMOVABLE(&cgd->inq_data))
                softc->flags |= CD_FLAG_DISC_REMOVABLE;
        if ((cgd->inq_data.flags & SID_CmdQue) != 0)
                softc->flags |= CD_FLAG_TAGGED_QUEUING;

        periph->softc = softc;
        softc->periph = periph;

        cam_extend_set(cdperiphs, periph->unit_number, periph);

        /*
         * See if this device has any quirks.
         */
        match = cam_quirkmatch((caddr_t)&cgd->inq_data,
                               (caddr_t)cd_quirk_table,
                               sizeof(cd_quirk_table)/sizeof(*cd_quirk_table),
                               sizeof(*cd_quirk_table), scsi_inquiry_match);

        if (match != NULL)
                softc->quirks = ((struct cd_quirk_entry *)match)->quirks;
        else
                softc->quirks = CD_Q_NONE;

        /* Check if the SIM does not want 6 byte commands */
        xpt_setup_ccb(&cpi.ccb_h, periph->path, /*priority*/1);
        cpi.ccb_h.func_code = XPT_PATH_INQ;
        xpt_action((union ccb *)&cpi);
        if (cpi.ccb_h.status == CAM_REQ_CMP && (cpi.hba_misc & PIM_NO_6_BYTE))
                softc->quirks |= CD_Q_10_BYTE_ONLY;

        TASK_INIT(&softc->sysctl_task, 0, cdsysctlinit, periph);

        /* The default is 6 byte commands, unless quirked otherwise */
        if (softc->quirks & CD_Q_10_BYTE_ONLY)
                softc->minimum_command_size = 10;
        else
                softc->minimum_command_size = 6;

        /*
         * Load the user's default, if any.
         */
        ksnprintf(tmpstr, sizeof(tmpstr), "kern.cam.cd.%d.minimum_cmd_size",
                periph->unit_number);
        TUNABLE_INT_FETCH(tmpstr, &softc->minimum_command_size);

        /* 6 and 10 are the only permissible values here. */
        if (softc->minimum_command_size < 6)
                softc->minimum_command_size = 6;
        else if (softc->minimum_command_size > 6)
                softc->minimum_command_size = 10;

        /*
         * We need to register the statistics structure for this device,
         * but we don't have the blocksize yet for it.  So, we register
         * the structure and indicate that we don't have the blocksize
         * yet.  Unlike other SCSI peripheral drivers, we explicitly set
         * the device type here to be CDROM, rather than just ORing in
         * the device type.  This is because this driver can attach to either
         * CDROM or WORM devices, and we want this peripheral driver to
         * show up in the devstat list as a CD peripheral driver, not a
         * WORM peripheral driver.  WORM drives will also have the WORM
         * driver attached to them.
         */
        cam_periph_unlock(periph);
        devstat_add_entry(&softc->device_stats, "cd", 
                          periph->unit_number, 0,
                          DEVSTAT_BS_UNAVAILABLE,
                          DEVSTAT_TYPE_CDROM | DEVSTAT_TYPE_IF_SCSI,
                          DEVSTAT_PRIORITY_CD);
        disk_create(periph->unit_number, &softc->disk, &cd_ops);
        softc->disk.d_rawdev->si_iosize_max = MAXPHYS;
        softc->disk.d_info.d_dsflags = DSO_ONESLICE | DSO_COMPATLABEL |
                                        DSO_COMPATPARTA;
        cam_periph_lock(periph);

        /*
         * Add an async callback so that we get
         * notified if this device goes away.
         */
        xpt_register_async(AC_SENT_BDR | AC_BUS_RESET | AC_LOST_DEVICE,
                           cdasync, periph, periph->path);

        /*
         * If the target lun is greater than 0, we most likely have a CD
         * changer device.  Check the quirk entries as well, though, just
         * in case someone has a CD tower with one lun per drive or
         * something like that.  Also, if we know up front that a
         * particular device is a changer, we can mark it as such starting
         * with lun 0, instead of lun 1.  It shouldn't be necessary to have
         * a quirk entry to define something as a changer, however.
         */
        if (((cgd->ccb_h.target_lun > 0)
          && ((softc->quirks & CD_Q_NO_CHANGER) == 0))
         || ((softc->quirks & CD_Q_CHANGER) != 0)) {
                struct cdchanger *nchanger;
                struct cam_periph *nperiph;
                struct cam_path *path;
                cam_status status;
                int found;

                /* Set the changer flag in the current device's softc */
                softc->flags |= CD_FLAG_CHANGER;

                /*
                 * Now, look around for an existing changer device with the
                 * same path and target ID as the current device.
                 */
                lockmgr(&changerq_lock, LK_EXCLUSIVE);
                for (found = 0,
                     nchanger = (struct cdchanger *)STAILQ_FIRST(&changerq);
                     nchanger != NULL;
                     nchanger = STAILQ_NEXT(nchanger, changer_links)){
                        if ((nchanger->path_id == cgd->ccb_h.path_id) 
                         && (nchanger->target_id == cgd->ccb_h.target_id)) {
                                found = 1;
                                break;
                        }
                }
                lockmgr(&changerq_lock, LK_RELEASE);

                /*
                 * If we found a matching entry, just add this device to
                 * the list of devices on this changer.
                 */
                if (found == 1) {
                        struct chdevlist *chlunhead;

                        chlunhead = &nchanger->chluns;

                        /*
                         * XXX KDM look at consolidating this code with the
                         * code below in a separate function.
                         */

                        /*
                         * Create a path with lun id 0, and see if we can
                         * find a matching device
                         */
                        status = xpt_create_path(&path, /*periph*/ periph,
                                                 cgd->ccb_h.path_id,
                                                 cgd->ccb_h.target_id, 0);

                        if ((status == CAM_REQ_CMP)
                         && ((nperiph = cam_periph_find(path, "cd")) != NULL)){
                                struct cd_softc *nsoftc;

                                nsoftc = (struct cd_softc *)nperiph->softc;

                                if ((nsoftc->flags & CD_FLAG_CHANGER) == 0){
                                        nsoftc->flags |= CD_FLAG_CHANGER;
                                        nchanger->num_devices++;
                                        if (camq_resize(&nchanger->devq,
                                           nchanger->num_devices)!=CAM_REQ_CMP){
                                                kprintf("cdregister: "
                                                       "camq_resize "
                                                       "failed, changer "
                                                       "support may "
                                                       "be messed up\n");
                                        }
                                        nsoftc->changer = nchanger;
                                        nsoftc->pinfo.index =CAM_UNQUEUED_INDEX;

                                        STAILQ_INSERT_TAIL(&nchanger->chluns,
                                                          nsoftc,changer_links);
                                }
                                xpt_free_path(path);
                        } else if (status == CAM_REQ_CMP)
                                xpt_free_path(path);
                        else {
                                kprintf("cdregister: unable to allocate path\n"
                                       "cdregister: changer support may be "
                                       "broken\n");
                        }

                        nchanger->num_devices++;

                        softc->changer = nchanger;
                        softc->pinfo.index = CAM_UNQUEUED_INDEX;

                        if (camq_resize(&nchanger->devq,
                            nchanger->num_devices) != CAM_REQ_CMP) {
                                kprintf("cdregister: camq_resize "
                                       "failed, changer support may "
                                       "be messed up\n");
                        }

                        STAILQ_INSERT_TAIL(chlunhead, softc, changer_links);
                }
                /*
                 * In this case, we don't already have an entry for this
                 * particular changer, so we need to create one, add it to
                 * the queue, and queue this device on the list for this
                 * changer.  Before we queue this device, however, we need
                 * to search for lun id 0 on this target, and add it to the
                 * queue first, if it exists.  (and if it hasn't already
                 * been marked as part of the changer.)
                 */
                else {
                        nchanger = kmalloc(sizeof(struct cdchanger),
                                        M_DEVBUF, M_INTWAIT | M_ZERO);
                        callout_init(&nchanger->short_handle);
                        callout_init(&nchanger->long_handle);
                        if (camq_init(&nchanger->devq, 1) != 0) {
                                softc->flags &= ~CD_FLAG_CHANGER;
                                kprintf("cdregister: changer support "
                                       "disabled\n");
                                goto cdregisterexit;
                        }

                        nchanger->path_id = cgd->ccb_h.path_id;
                        nchanger->target_id = cgd->ccb_h.target_id;

                        /* this is superfluous, but it makes things clearer */
                        nchanger->num_devices = 0;

                        STAILQ_INIT(&nchanger->chluns);

                        callout_init(&nchanger->long_handle);
                        callout_init(&nchanger->short_handle);

                        lockmgr(&changerq_lock, LK_EXCLUSIVE);
                        num_changers++;
                        STAILQ_INSERT_TAIL(&changerq, nchanger,
                                           changer_links);
                        lockmgr(&changerq_lock, LK_RELEASE);
                        
                        /*
                         * Create a path with lun id 0, and see if we can
                         * find a matching device
                         */
                        status = xpt_create_path(&path, /*periph*/ periph,
                                                 cgd->ccb_h.path_id,
                                                 cgd->ccb_h.target_id, 0);

                        /*
                         * If we were able to allocate the path, and if we
                         * find a matching device and it isn't already
                         * marked as part of a changer, then we add it to
                         * the current changer.
                         */
                        if ((status == CAM_REQ_CMP)
                         && ((nperiph = cam_periph_find(path, "cd")) != NULL)
                         && ((((struct cd_softc *)periph->softc)->flags &
                               CD_FLAG_CHANGER) == 0)) {
                                struct cd_softc *nsoftc;

                                nsoftc = (struct cd_softc *)nperiph->softc;

                                nsoftc->flags |= CD_FLAG_CHANGER;
                                nchanger->num_devices++;
                                if (camq_resize(&nchanger->devq,
                                    nchanger->num_devices) != CAM_REQ_CMP) {
                                        kprintf("cdregister: camq_resize "
                                               "failed, changer support may "
                                               "be messed up\n");
                                }
                                nsoftc->changer = nchanger;
                                nsoftc->pinfo.index = CAM_UNQUEUED_INDEX;

                                STAILQ_INSERT_TAIL(&nchanger->chluns,
                                                   nsoftc, changer_links);
                                xpt_free_path(path);
                        } else if (status == CAM_REQ_CMP)
                                xpt_free_path(path);
                        else {
                                kprintf("cdregister: unable to allocate path\n"
                                       "cdregister: changer support may be "
                                       "broken\n");
                        }

                        softc->changer = nchanger;
                        softc->pinfo.index = CAM_UNQUEUED_INDEX;
                        nchanger->num_devices++;
                        if (camq_resize(&nchanger->devq,
                            nchanger->num_devices) != CAM_REQ_CMP) {
                                kprintf("cdregister: camq_resize "
                                       "failed, changer support may "
                                       "be messed up\n");
                        }
                        STAILQ_INSERT_TAIL(&nchanger->chluns, softc,
                                           changer_links);
                }
        }

cdregisterexit:

        /*
         * Refcount and block open attempts until we are setup
         * Can't block
         */
        cam_periph_hold(periph, 0);

        if ((softc->flags & CD_FLAG_CHANGER) == 0)
                xpt_schedule(periph, /*priority*/5);
        else
                cdschedule(periph, /*priority*/ 5);

        return(CAM_REQ_CMP);
}

static int
cdopen(struct dev_open_args *ap)
{
        cdev_t dev = ap->a_head.a_dev;
        struct cam_periph *periph;
        struct cd_softc *softc;
        int unit, error;

        unit = dkunit(dev);
        periph = cam_extend_get(cdperiphs, unit);

        if (periph == NULL)
                return (ENXIO);

        softc = (struct cd_softc *)periph->softc;

        if (cam_periph_acquire(periph) != CAM_REQ_CMP)
                return(ENXIO);

        cam_periph_lock(periph);

        if (softc->flags & CD_FLAG_INVALID) {
                cam_periph_unlock(periph);
                cam_periph_release(periph);
                return(ENXIO);
        }

        if ((error = cam_periph_hold(periph, PCATCH)) != 0) {
                cam_periph_unlock(periph);
                cam_periph_release(periph);
                return (error);
        }

        /* Closes aren't symmetrical with opens, so fix up the refcounting. */
        if (softc->flags & CD_FLAG_OPEN)
                cam_periph_release(periph);
        else
                softc->flags |= CD_FLAG_OPEN;

        /*
         * Check for media, and set the appropriate flags.  We don't bail
         * if we don't have media, but then we don't allow anything but the
         * CDIOCEJECT/CDIOCCLOSE ioctls if there is no media.
         *
         * XXX KDM for now, we do fail the open if we don't have media.  We
         * can change this once we've figured out how to make the slice
         * code work well with media changing underneath it.
         */
        error = cdcheckmedia(periph);

        if (error == 0)
                softc->flags |= CD_FLAG_OPEN;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("leaving cdopen\n"));
        cam_periph_unhold(periph);
        cam_periph_unlock(periph);

        return (0);
}

static int
cdclose(struct dev_close_args *ap)
{
        cdev_t dev = ap->a_head.a_dev;
        struct  cam_periph *periph;
        struct  cd_softc *softc;
        struct  disk_info *info;
        int     unit;

        unit = dkunit(dev);
        periph = cam_extend_get(cdperiphs, unit);
        if (periph == NULL)
                return (ENXIO); 

        softc = (struct cd_softc *)periph->softc;

        cam_periph_lock(periph);
        cam_periph_hold(periph, 0);

        if ((softc->flags & CD_FLAG_DISC_REMOVABLE) != 0)
                cdprevent(periph, PR_ALLOW);

        /*
         * Unconditionally set the dsopen() flags back to their default
         * state.
         */
        info = &softc->disk.d_info;
        info->d_dsflags &= ~DSO_NOLABELS;
        info->d_dsflags |= DSO_COMPATLABEL;

        /*
         * Since we're closing this CD, mark the blocksize as unavailable.
         * It will be marked as available when the CD is opened again.
         */
        softc->device_stats.flags |= DEVSTAT_BS_UNAVAILABLE;

        /*
         * We'll check the media and toc again at the next open().
         */
        softc->flags &= ~(CD_FLAG_VALID_MEDIA|CD_FLAG_VALID_TOC|CD_FLAG_OPEN);

        cam_periph_unhold(periph);
        cam_periph_unlock(periph);
        cam_periph_release(periph);

        return (0);
}

static void
cdshorttimeout(void *arg)
{
        struct cdchanger *changer;

        changer = (struct cdchanger *)arg;

        /* Always clear the short timeout flag, since that's what we're in */
        changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;

        /*
         * Check to see if there is any more pending or outstanding I/O for
         * this device.  If not, move it out of the active slot.
         */
        if ((bioq_first(&changer->cur_device->bio_queue) == NULL)
         && (changer->cur_device->outstanding_cmds == 0)) {
                changer->flags |= CHANGER_MANUAL_CALL;
                cdrunchangerqueue(changer);
        }
}

/*
 * This is a wrapper for xpt_schedule.  It only applies to changers.
 */
static void
cdschedule(struct cam_periph *periph, int priority)
{
        struct cd_softc *softc;

        softc = (struct cd_softc *)periph->softc;

        /*
         * If this device isn't currently queued, and if it isn't
         * the active device, then we queue this device and run the
         * changer queue if there is no timeout scheduled to do it.
         * If this device is the active device, just schedule it
         * to run again.  If this device is queued, there should be
         * a timeout in place already that will make sure it runs.
         */
        if ((softc->pinfo.index == CAM_UNQUEUED_INDEX) 
         && ((softc->flags & CD_FLAG_ACTIVE) == 0)) {
                /*
                 * We don't do anything with the priority here.
                 * This is strictly a fifo queue.
                 */
                softc->pinfo.priority = 1;
                softc->pinfo.generation = ++softc->changer->devq.generation;
                camq_insert(&softc->changer->devq, (cam_pinfo *)softc);

                /*
                 * Since we just put a device in the changer queue,
                 * check and see if there is a timeout scheduled for
                 * this changer.  If so, let the timeout handle
                 * switching this device into the active slot.  If
                 * not, manually call the timeout routine to
                 * bootstrap things.
                 */
                if (((softc->changer->flags & CHANGER_TIMEOUT_SCHED)==0)
                 && ((softc->changer->flags & CHANGER_NEED_TIMEOUT)==0)
                 && ((softc->changer->flags & CHANGER_SHORT_TMOUT_SCHED)==0)){
                        softc->changer->flags |= CHANGER_MANUAL_CALL;
                        cdrunchangerqueue(softc->changer);
                }
        } else if ((softc->flags & CD_FLAG_ACTIVE)
                && ((softc->flags & CD_FLAG_SCHED_ON_COMP) == 0)) {
                xpt_schedule(periph, priority);
        }
}

static void
cdrunchangerqueue(void *arg)
{
        struct cd_softc *softc;
        struct cdchanger *changer;
        int called_from_timeout;

        changer = (struct cdchanger *)arg;

        /*
         * If we have NOT been called from cdstrategy() or cddone(), and
         * instead from a timeout routine, go ahead and clear the
         * timeout flag.
         */
        if ((changer->flags & CHANGER_MANUAL_CALL) == 0) {
                changer->flags &= ~CHANGER_TIMEOUT_SCHED;
                called_from_timeout = 1;
        } else
                called_from_timeout = 0;

        /* Always clear the manual call flag */
        changer->flags &= ~CHANGER_MANUAL_CALL;

        /* nothing to do if the queue is empty */
        if (changer->devq.entries <= 0) {
                return;
        }

        /*
         * If the changer queue is frozen, that means we have an active
         * device.
         */
        if (changer->devq.qfrozen_cnt > 0) {

                /*
                 * We always need to reset the frozen count and clear the
                 * active flag.
                 */
                changer->devq.qfrozen_cnt--;
                changer->cur_device->flags &= ~CD_FLAG_ACTIVE;
                changer->cur_device->flags &= ~CD_FLAG_SCHED_ON_COMP;

                if (changer->cur_device->outstanding_cmds > 0) {
                        changer->cur_device->flags |= CD_FLAG_SCHED_ON_COMP;
                        changer->cur_device->bufs_left = 
                                changer->cur_device->outstanding_cmds;
                        if (called_from_timeout) {
                                callout_reset(&changer->long_handle,
                                        changer_max_busy_seconds * hz,
                                        cdrunchangerqueue, changer);
                                changer->flags |= CHANGER_TIMEOUT_SCHED;
                        }
                        return;
                }

                /*
                 * Check to see whether the current device has any I/O left
                 * to do.  If so, requeue it at the end of the queue.  If
                 * not, there is no need to requeue it.
                 */
                if (bioq_first(&changer->cur_device->bio_queue) != NULL) {

                        changer->cur_device->pinfo.generation =
                                ++changer->devq.generation;
                        camq_insert(&changer->devq,
                                (cam_pinfo *)changer->cur_device);
                } 
        }

        softc = (struct cd_softc *)camq_remove(&changer->devq, CAMQ_HEAD);

        changer->cur_device = softc;

        changer->devq.qfrozen_cnt++;
        softc->flags |= CD_FLAG_ACTIVE;

        /* Just in case this device is waiting */
        wakeup(&softc->changer);
        xpt_schedule(softc->periph, /*priority*/ 1);

        /*
         * Get rid of any pending timeouts, and set a flag to schedule new
         * ones so this device gets its full time quantum.
         */
        if (changer->flags & CHANGER_TIMEOUT_SCHED) {
                callout_stop(&changer->long_handle);
                changer->flags &= ~CHANGER_TIMEOUT_SCHED;
        }

        if (changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
                callout_stop(&changer->short_handle);
                changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
        }

        /*
         * We need to schedule timeouts, but we only do this after the
         * first transaction has completed.  This eliminates the changer
         * switch time.
         */
        changer->flags |= CHANGER_NEED_TIMEOUT;
}

static void
cdchangerschedule(struct cd_softc *softc)
{
        struct cdchanger *changer;

        changer = softc->changer;

        /*
         * If this is a changer, and this is the current device,
         * and this device has at least the minimum time quantum to
         * run, see if we can switch it out.
         */
        if ((softc->flags & CD_FLAG_ACTIVE) 
         && ((changer->flags & CHANGER_SHORT_TMOUT_SCHED) == 0)
         && ((changer->flags & CHANGER_NEED_TIMEOUT) == 0)) {
                /*
                 * We try three things here.  The first is that we
                 * check to see whether the schedule on completion
                 * flag is set.  If it is, we decrement the number
                 * of buffers left, and if it's zero, we reschedule.
                 * Next, we check to see whether the pending buffer
                 * queue is empty and whether there are no
                 * outstanding transactions.  If so, we reschedule.
                 * Next, we see if the pending buffer queue is empty.
                 * If it is, we set the number of buffers left to
                 * the current active buffer count and set the
                 * schedule on complete flag.
                 */
                if (softc->flags & CD_FLAG_SCHED_ON_COMP) {
                        if (--softc->bufs_left == 0) {
                                softc->changer->flags |=
                                        CHANGER_MANUAL_CALL;
                                softc->flags &= ~CD_FLAG_SCHED_ON_COMP;
                                cdrunchangerqueue(softc->changer);
                        }
                } else if ((bioq_first(&softc->bio_queue) == NULL)
                        && (softc->outstanding_cmds == 0)) {
                        softc->changer->flags |= CHANGER_MANUAL_CALL;
                        cdrunchangerqueue(softc->changer);
                }
        } else if ((softc->changer->flags & CHANGER_NEED_TIMEOUT) 
                && (softc->flags & CD_FLAG_ACTIVE)) {

                /*
                 * Now that the first transaction to this
                 * particular device has completed, we can go ahead
                 * and schedule our timeouts.
                 */
                if ((changer->flags & CHANGER_TIMEOUT_SCHED) == 0) {
                        callout_reset(&changer->long_handle,
                                    changer_max_busy_seconds * hz,
                                    cdrunchangerqueue, changer);
                        changer->flags |= CHANGER_TIMEOUT_SCHED;
                } else
                        kprintf("cdchangerschedule: already have a long"
                               " timeout!\n");

                if ((changer->flags & CHANGER_SHORT_TMOUT_SCHED) == 0) {
                        callout_reset(&changer->short_handle,
                                        changer_min_busy_seconds * hz,
                                        cdshorttimeout, changer);
                        changer->flags |= CHANGER_SHORT_TMOUT_SCHED;
                } else
                        kprintf("cdchangerschedule: already have a short "
                               "timeout!\n");

                /*
                 * We just scheduled timeouts, no need to schedule
                 * more.
                 */
                changer->flags &= ~CHANGER_NEED_TIMEOUT;

        }
}

static int
cdrunccb(union ccb *ccb, int (*error_routine)(union ccb *ccb,
                                              u_int32_t cam_flags,
                                              u_int32_t sense_flags),
         u_int32_t cam_flags, u_int32_t sense_flags)
{
        struct cd_softc *softc;
        struct cam_periph *periph;
        int error;

        periph = xpt_path_periph(ccb->ccb_h.path);
        softc = (struct cd_softc *)periph->softc;

        error = cam_periph_runccb(ccb, error_routine, cam_flags, sense_flags,
                                  &softc->device_stats);

        if (softc->flags & CD_FLAG_CHANGER)
                cdchangerschedule(softc);

        return(error);
}

static union ccb *
cdgetccb(struct cam_periph *periph, u_int32_t priority)
{
        struct cd_softc *softc;

        softc = (struct cd_softc *)periph->softc;

        if (softc->flags & CD_FLAG_CHANGER) {
                /*
                 * This should work the first time this device is woken up,
                 * but just in case it doesn't, we use a while loop.
                 */
                while ((softc->flags & CD_FLAG_ACTIVE) == 0) {
                        /*
                         * If this changer isn't already queued, queue it up.
                         */
                        if (softc->pinfo.index == CAM_UNQUEUED_INDEX) {
                                softc->pinfo.priority = 1;
                                softc->pinfo.generation =
                                        ++softc->changer->devq.generation;
                                camq_insert(&softc->changer->devq,
                                            (cam_pinfo *)softc);
                        }
                        if (((softc->changer->flags & CHANGER_TIMEOUT_SCHED)==0)
                         && ((softc->changer->flags & CHANGER_NEED_TIMEOUT)==0)
                         && ((softc->changer->flags
                              & CHANGER_SHORT_TMOUT_SCHED)==0)) {
                                softc->changer->flags |= CHANGER_MANUAL_CALL;
                                cdrunchangerqueue(softc->changer);
                        } else
                                sim_lock_sleep(&softc->changer, 0, "cgticb", 0,
                                               periph->sim->lock);
                }
        }
        return(cam_periph_getccb(periph, priority));
}

/*
 * Actually translate the requested transfer into one the physical driver
 * can understand.  The transfer is described by a buf and will include
 * only one physical transfer.
 */
static int
cdstrategy(struct dev_strategy_args *ap)
{
        cdev_t dev = ap->a_head.a_dev;
        struct bio *bio = ap->a_bio;
        struct buf *bp = bio->bio_buf;
        struct cam_periph *periph;
        struct cd_softc *softc;
        u_int  unit;

        unit = dkunit(dev);
        periph = cam_extend_get(cdperiphs, unit);
        if (periph == NULL) {
                bp->b_error = ENXIO;
                goto bad;
        }

        cam_periph_lock(periph);
        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdstrategy\n"));

        softc = (struct cd_softc *)periph->softc;

        /*
         * If the device has been made invalid, error out
         */
        if ((softc->flags & CD_FLAG_INVALID)) {
                cam_periph_unlock(periph);
                bp->b_error = ENXIO;
                goto bad;
        }

        /*
         * If we don't have valid media, look for it before trying to
         * schedule the I/O.
         */
        if ((softc->flags & CD_FLAG_VALID_MEDIA) == 0) {
                int error;

                error = cdcheckmedia(periph);
                if (error != 0) {
                        cam_periph_unlock(periph);
                        bp->b_error = error;
                        goto bad;
                }
        }

        /*
         * Place it in the queue of disk activities for this disk
         */
        bioqdisksort(&softc->bio_queue, bio);

        /*
         * Schedule ourselves for performing the work.  We do things
         * differently for changers.
         */
        if ((softc->flags & CD_FLAG_CHANGER) == 0)
                xpt_schedule(periph, /* XXX priority */1);
        else
                cdschedule(periph, /* priority */ 1);

        cam_periph_unlock(periph);
        return(0);
bad:
        bp->b_flags |= B_ERROR;
        /*
         * Correctly set the buf to indicate a completed xfer
         */
        bp->b_resid = bp->b_bcount;
        biodone(bio);
        return(0);
}

static void
cdstart(struct cam_periph *periph, union ccb *start_ccb)
{
        struct cd_softc *softc;
        struct bio *bio;
        struct buf *bp;
        struct ccb_scsiio *csio;
        struct scsi_read_capacity_data *rcap;

        softc = (struct cd_softc *)periph->softc;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdstart\n"));

        switch (softc->state) {
        case CD_STATE_NORMAL:
        {
                bio = bioq_first(&softc->bio_queue);
                if (periph->immediate_priority <= periph->pinfo.priority) {
                        start_ccb->ccb_h.ccb_state = CD_CCB_WAITING;

                        SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
                                          periph_links.sle);
                        periph->immediate_priority = CAM_PRIORITY_NONE;
                        wakeup(&periph->ccb_list);
                } else if (bio == NULL) {
                        xpt_release_ccb(start_ccb);
                } else {
                        bp = bio->bio_buf;
                        bioq_remove(&softc->bio_queue, bio);

                        devstat_start_transaction(&softc->device_stats);

                        KKASSERT(bio->bio_offset % softc->params.blksize == 0);

                        scsi_read_write(&start_ccb->csio,
                                        /*retries*/4,
                                        /* cbfcnp */ cddone,
                                        (bp->b_flags & B_ORDERED) != 0 ?
                                            MSG_ORDERED_Q_TAG : 
                                            MSG_SIMPLE_Q_TAG,
                                        /* read */(bp->b_cmd == BUF_CMD_READ),
                                        /* byte2 */ 0,
                                        /* minimum_cmd_size */ 10,
                                        /* lba */ 
                                        bio->bio_offset / softc->params.blksize,
                                        bp->b_bcount / softc->params.blksize,
                                        /* data_ptr */ bp->b_data,
                                        /* dxfer_len */ bp->b_bcount,
                                        /* sense_len */ SSD_FULL_SIZE,
                                        /* timeout */ 30000);
                        start_ccb->ccb_h.ccb_state = CD_CCB_BUFFER_IO;

                        
                        LIST_INSERT_HEAD(&softc->pending_ccbs,
                                         &start_ccb->ccb_h, periph_links.le);

                        softc->outstanding_cmds++;
                        /* We expect a unit attention from this device */
                        if ((softc->flags & CD_FLAG_RETRY_UA) != 0) {
                                start_ccb->ccb_h.ccb_state |= CD_CCB_RETRY_UA;
                                softc->flags &= ~CD_FLAG_RETRY_UA;
                        }

                        start_ccb->ccb_h.ccb_bio = bio;
                        bio = bioq_first(&softc->bio_queue);

                        xpt_action(start_ccb);
                }
                if (bio != NULL) {
                        /* Have more work to do, so ensure we stay scheduled */
                        xpt_schedule(periph, /* XXX priority */1);
                }
                break;
        }
        case CD_STATE_PROBE:
        {

                rcap = kmalloc(sizeof(*rcap), M_SCSICD, M_INTWAIT);
                csio = &start_ccb->csio;
                scsi_read_capacity(csio,
                                   /*retries*/1,
                                   cddone,
                                   MSG_SIMPLE_Q_TAG,
                                   rcap,
                                   SSD_FULL_SIZE,
                                   /*timeout*/20000);
                start_ccb->ccb_h.ccb_bio = NULL;
                start_ccb->ccb_h.ccb_state = CD_CCB_PROBE;
                xpt_action(start_ccb);
                break;
        }
        }
}

static void
cddone(struct cam_periph *periph, union ccb *done_ccb)
{ 
        struct cd_softc *softc;
        struct ccb_scsiio *csio;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cddone\n"));

        softc = (struct cd_softc *)periph->softc;
        csio = &done_ccb->csio;

        switch (csio->ccb_h.ccb_state & CD_CCB_TYPE_MASK) {
        case CD_CCB_BUFFER_IO:
        {
                struct buf      *bp;
                struct bio      *bio;
                int             error;

                bio = (struct bio *)done_ccb->ccb_h.ccb_bio;
                bp = bio->bio_buf;
                error = 0;

                if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
                        int sf;

                        if ((done_ccb->ccb_h.ccb_state & CD_CCB_RETRY_UA) != 0)
                                sf = SF_RETRY_UA;
                        else
                                sf = 0;

                        error = cderror(done_ccb, CAM_RETRY_SELTO, sf);
                        if (error == ERESTART) {
                                /*
                                 * A retry was scheuled, so
                                 * just return.
                                 */
                                return;
                        }
                }

                if (error != 0) {
                        struct bio *q_bio;
                        struct buf *q_bp;

                        xpt_print(periph->path,
                                  "cddone: got error %#x back\n", error);
                        while ((q_bio = bioq_first(&softc->bio_queue)) != NULL) {
                                bioq_remove(&softc->bio_queue, q_bio);
                                q_bp = q_bio->bio_buf;
                                q_bp->b_resid = q_bp->b_bcount;
                                q_bp->b_error = EIO;
                                q_bp->b_flags |= B_ERROR;
                                biodone(q_bio);
                        }
                        bp->b_resid = bp->b_bcount;
                        bp->b_error = error;
                        bp->b_flags |= B_ERROR;
                        cam_release_devq(done_ccb->ccb_h.path,
                                         /*relsim_flags*/0,
                                         /*reduction*/0,
                                         /*timeout*/0,
                                         /*getcount_only*/0);

                } else {
                        bp->b_resid = csio->resid;
                        bp->b_error = 0;
                        if (bp->b_resid != 0) {
                                /* Short transfer ??? */
                                bp->b_flags |= B_ERROR;
                        }
                }

                LIST_REMOVE(&done_ccb->ccb_h, periph_links.le);
                softc->outstanding_cmds--;

                if (softc->flags & CD_FLAG_CHANGER)
                        cdchangerschedule(softc);

                devstat_end_transaction_buf(&softc->device_stats, bp);
                biodone(bio);
                break;
        }
        case CD_CCB_PROBE:
        {
                struct     scsi_read_capacity_data *rdcap;
                char       announce_buf[120]; /*
                                               * Currently (9/30/97) the 
                                               * longest possible announce 
                                               * buffer is 108 bytes, for the 
                                               * first error case below.  
                                               * That is 39 bytes for the 
                                               * basic string, 16 bytes for the
                                               * biggest sense key (hardware 
                                               * error), 52 bytes for the
                                               * text of the largest sense 
                                               * qualifier valid for a CDROM,
                                               * (0x72, 0x03 or 0x04,
                                               * 0x03), and one byte for the
                                               * null terminating character.
                                               * To allow for longer strings, 
                                               * the announce buffer is 120
                                               * bytes.
                                               */
                struct     cd_params *cdp;

                cdp = &softc->params;

                rdcap = (struct scsi_read_capacity_data *)csio->data_ptr;
                
                cdp->disksize = scsi_4btoul (rdcap->addr) + 1;
                cdp->blksize = scsi_4btoul (rdcap->length);

                if ((csio->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_CMP) {

                        ksnprintf(announce_buf, sizeof(announce_buf),
                                "cd present [%lu x %lu byte records]",
                                cdp->disksize, (u_long)cdp->blksize);

                } else {
                        int     error;
                        /*
                         * Retry any UNIT ATTENTION type errors.  They
                         * are expected at boot.
                         */
                        error = cderror(done_ccb, CAM_RETRY_SELTO,
                                        SF_RETRY_UA | SF_NO_PRINT);
                        if (error == ERESTART) {
                                /*
                                 * A retry was scheuled, so
                                 * just return.
                                 */
                                return;
                        } else if (error != 0) {

                                struct scsi_sense_data *sense;
                                int asc, ascq;
                                int sense_key, error_code;
                                int have_sense;
                                cam_status status;
                                struct ccb_getdev cgd;

                                /* Don't wedge this device's queue */
                                cam_release_devq(done_ccb->ccb_h.path,
                                                 /*relsim_flags*/0,
                                                 /*reduction*/0,
                                                 /*timeout*/0,
                                                 /*getcount_only*/0);

                                status = done_ccb->ccb_h.status;

                                xpt_setup_ccb(&cgd.ccb_h, 
                                              done_ccb->ccb_h.path,
                                              /* priority */ 1);
                                cgd.ccb_h.func_code = XPT_GDEV_TYPE;
                                xpt_action((union ccb *)&cgd);

                                if (((csio->ccb_h.flags & CAM_SENSE_PHYS) != 0)
                                 || ((csio->ccb_h.flags & CAM_SENSE_PTR) != 0)
                                 || ((status & CAM_AUTOSNS_VALID) == 0))
                                        have_sense = FALSE;
                                else
                                        have_sense = TRUE;

                                if (have_sense) {
                                        sense = &csio->sense_data;
                                        scsi_extract_sense(sense, &error_code,
                                                           &sense_key, 
                                                           &asc, &ascq);
                                }
                                /*
                                 * Attach to anything that claims to be a
                                 * CDROM or WORM device, as long as it
                                 * doesn't return a "Logical unit not
                                 * supported" (0x25) error.
                                 */
                                if ((have_sense) && (asc != 0x25)
                                 && (error_code == SSD_CURRENT_ERROR)) {
                                        const char *sense_key_desc;
                                        const char *asc_desc;

                                        scsi_sense_desc(sense_key, asc, ascq,
                                                        &cgd.inq_data,
                                                        &sense_key_desc,
                                                        &asc_desc);
                                        ksnprintf(announce_buf,
                                            sizeof(announce_buf),
                                                "Attempt to query device "
                                                "size failed: %s, %s",
                                                sense_key_desc,
                                                asc_desc);
                                } else if (SID_TYPE(&cgd.inq_data) == T_CDROM) {
                                        /*
                                         * We only print out an error for
                                         * CDROM type devices.  For WORM
                                         * devices, we don't print out an
                                         * error since a few WORM devices
                                         * don't support CDROM commands.
                                         * If we have sense information, go
                                         * ahead and print it out.
                                         * Otherwise, just say that we 
                                         * couldn't attach.
                                         */

                                        /*
                                         * Just print out the error, not
                                         * the full probe message, when we
                                         * don't attach.
                                         */
                                        if (have_sense)
                                                scsi_sense_print(
                                                        &done_ccb->csio);
                                        else {
                                                xpt_print(periph->path,
                                                    "got CAM status %#x\n",
                                                    done_ccb->ccb_h.status);
                                        }
                                        xpt_print(periph->path, "fatal error, "
                                            "failed to attach to device\n");
                                        /*
                                         * Invalidate this peripheral.
                                         */
                                        cam_periph_invalidate(periph);

                                        announce_buf[0] = '\0';
                                } else {

                                        /*
                                         * Invalidate this peripheral.
                                         */
                                        cam_periph_invalidate(periph);
                                        announce_buf[0] = '\0';
                                }
                        }
                }
                kfree(rdcap, M_SCSICD);
                if (announce_buf[0] != '\0') {
                        xpt_announce_periph(periph, announce_buf);
                        if (softc->flags & CD_FLAG_CHANGER)
                                cdchangerschedule(softc);
                        /*
                         * Create our sysctl variables, now that we know
                         * we have successfully attached.
                         */
                        taskqueue_enqueue(taskqueue_thread[mycpuid],
                            &softc->sysctl_task);
                }
                softc->state = CD_STATE_NORMAL;         
                /*
                 * Since our peripheral may be invalidated by an error
                 * above or an external event, we must release our CCB
                 * before releasing the probe lock on the peripheral.
                 * The peripheral will only go away once the last lock
                 * is removed, and we need it around for the CCB release
                 * operation.
                 */
                xpt_release_ccb(done_ccb);
                cam_periph_unhold(periph);
                return;
        }
        case CD_CCB_WAITING:
        {
                /* Caller will release the CCB */
                CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, 
                          ("trying to wakeup ccbwait\n"));

                wakeup(&done_ccb->ccb_h.cbfcnp);
                return;
        }
        default:
                break;
        }
        xpt_release_ccb(done_ccb);
}

static union cd_pages *
cdgetpage(struct cd_mode_params *mode_params)
{
        union cd_pages *page;

        if (mode_params->cdb_size == 10)
                page = (union cd_pages *)find_mode_page_10(
                        (struct scsi_mode_header_10 *)mode_params->mode_buf);
        else
                page = (union cd_pages *)find_mode_page_6(
                        (struct scsi_mode_header_6 *)mode_params->mode_buf);

        return (page);
}

static int
cdgetpagesize(int page_num)
{
        int i;

        for (i = 0; i < (sizeof(cd_page_size_table)/
            sizeof(cd_page_size_table[0])); i++) {
                if (cd_page_size_table[i].page == page_num)
                        return (cd_page_size_table[i].page_size);
        }
        return (-1);
}

static int
cdioctl(struct dev_ioctl_args *ap)
{
        cdev_t dev = ap->a_head.a_dev;
        caddr_t addr = ap->a_data;
        struct  cam_periph *periph;
        struct  cd_softc *softc;
        int     unit, error = 0;

        unit = dkunit(dev);

        periph = cam_extend_get(cdperiphs, unit);
        if (periph == NULL)
                return(ENXIO);  

        cam_periph_lock(periph);
        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdioctl\n"));

        softc = (struct cd_softc *)periph->softc;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, 
                  ("trying to do ioctl %#lx\n", ap->a_cmd));

        if ((error = cam_periph_hold(periph, PCATCH)) != 0) {
                cam_periph_unlock(periph);
                cam_periph_release(periph);
                return (error);
        }

        /*
         * If we don't have media loaded, check for it.  If still don't
         * have media loaded, we can only do a load or eject.
         *
         * We only care whether media is loaded if this is a cd-specific ioctl
         * (thus the IOCGROUP check below).  Note that this will break if
         * anyone adds any ioctls into the switch statement below that don't
         * have their ioctl group set to 'c'.
         */
        if (((softc->flags & CD_FLAG_VALID_MEDIA) == 0)
            && ((ap->a_cmd != CDIOCCLOSE)
            && (ap->a_cmd != CDIOCEJECT))
            && (IOCGROUP(ap->a_cmd) == 'c')) {
                error = cdcheckmedia(periph);
                if (error != 0) {
                        cam_periph_unhold(periph);
                        cam_periph_unlock(periph);
                        return (error);
                }
        }
        /*
         * Drop the lock here so later mallocs can use WAITOK.  The periph
         * is essentially locked still with the cam_periph_hold call above.
         */
        cam_periph_unlock(periph);

        switch (ap->a_cmd) {

        case CDIOCPLAYTRACKS:
                {
                        struct ioc_play_track *args
                            = (struct ioc_play_track *)addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCPLAYTRACKS\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.flags &= ~CD_PA_SOTC;
                        page->audio.flags |= CD_PA_IMMED;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        if (error) {
                                cam_periph_unlock(periph);
                                break;
                        }

                        /*
                         * This was originally implemented with the PLAY
                         * AUDIO TRACK INDEX command, but that command was
                         * deprecated after SCSI-2.  Most (all?) SCSI CDROM
                         * drives support it but ATAPI and ATAPI-derivative
                         * drives don't seem to support it.  So we keep a
                         * cache of the table of contents and translate
                         * track numbers to MSF format.
                         */
                        if (softc->flags & CD_FLAG_VALID_TOC) {
                                union msf_lba *sentry, *eentry;
                                int st, et;

                                if (args->end_track <
                                    softc->toc.header.ending_track + 1)
                                        args->end_track++;
                                if (args->end_track >
                                    softc->toc.header.ending_track + 1)
                                        args->end_track =
                                            softc->toc.header.ending_track + 1;
                                st = args->start_track -
                                        softc->toc.header.starting_track;
                                et = args->end_track -
                                        softc->toc.header.starting_track;
                                if ((st < 0)
                                 || (et < 0)
                                 || (st > (softc->toc.header.ending_track -
                                     softc->toc.header.starting_track))) {
                                        error = EINVAL;
                                        break;
                                }
                                sentry = &softc->toc.entries[st].addr;
                                eentry = &softc->toc.entries[et].addr;
                                error = cdplaymsf(periph,
                                                  sentry->msf.minute,
                                                  sentry->msf.second,
                                                  sentry->msf.frame,
                                                  eentry->msf.minute,
                                                  eentry->msf.second,
                                                  eentry->msf.frame);
                        } else {
                                /*
                                 * If we don't have a valid TOC, try the
                                 * play track index command.  It is part of
                                 * the SCSI-2 spec, but was removed in the
                                 * MMC specs.  ATAPI and ATAPI-derived
                                 * drives don't support it.
                                 */
                                if (softc->quirks & CD_Q_BCD_TRACKS) {
                                        args->start_track =
                                                bin2bcd(args->start_track);
                                        args->end_track =
                                                bin2bcd(args->end_track);
                                }
                                error = cdplaytracks(periph,
                                                     args->start_track,
                                                     args->start_index,
                                                     args->end_track,
                                                     args->end_index);
                        }
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCPLAYMSF:
                {
                        struct ioc_play_msf *args
                                = (struct ioc_play_msf *) addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCPLAYMSF\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.flags &= ~CD_PA_SOTC;
                        page->audio.flags |= CD_PA_IMMED;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        if (error) {
                                cam_periph_unlock(periph);
                                break;
                        }
                        error = cdplaymsf(periph,
                                          args->start_m,
                                          args->start_s,
                                          args->start_f,
                                          args->end_m,
                                          args->end_s,
                                          args->end_f);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCPLAYBLOCKS:
                {
                        struct ioc_play_blocks *args
                                = (struct ioc_play_blocks *) addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);
                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCPLAYBLOCKS\n"));


                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.flags &= ~CD_PA_SOTC;
                        page->audio.flags |= CD_PA_IMMED;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        if (error) {
                                cam_periph_unlock(periph);
                                break;
                        }
                        error = cdplay(periph, args->blk, args->len);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCREADSUBCHANNEL:
                {
                        struct ioc_read_subchannel *args
                                = (struct ioc_read_subchannel *) addr;
                        struct cd_sub_channel_info *data;
                        u_int32_t len = args->data_len;

                        data = kmalloc(sizeof(struct cd_sub_channel_info),
                                      M_SCSICD, M_WAITOK);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCREADSUBCHANNEL\n"));

                        if ((len > sizeof(struct cd_sub_channel_info)) ||
                            (len < sizeof(struct cd_sub_channel_header))) {
                                kprintf(
                                        "scsi_cd: cdioctl: "
                                        "cdioreadsubchannel: error, len=%d\n",
                                        len);
                                error = EINVAL;
                                kfree(data, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }

                        if (softc->quirks & CD_Q_BCD_TRACKS)
                                args->track = bin2bcd(args->track);

                        error = cdreadsubchannel(periph, args->address_format,
                                args->data_format, args->track, data, len);

                        if (error) {
                                kfree(data, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        if (softc->quirks & CD_Q_BCD_TRACKS)
                                data->what.track_info.track_number =
                                    bcd2bin(data->what.track_info.track_number);
                        len = min(len, ((data->header.data_len[0] << 8) +
                                data->header.data_len[1] +
                                sizeof(struct cd_sub_channel_header)));
                        cam_periph_unlock(periph);
                        if (copyout(data, args->data, len) != 0) {
                                error = EFAULT;
                        }
                        kfree(data, M_SCSICD);
                }
                break;

        case CDIOREADTOCHEADER:
                {
                        struct ioc_toc_header *th;

                        th = kmalloc(sizeof(struct ioc_toc_header), M_SCSICD,
                                    M_WAITOK);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOREADTOCHEADER\n"));

                        error = cdreadtoc(periph, 0, 0, (u_int8_t *)th, 
                                          sizeof (*th), /*sense_flags*/0);
                        if (error) {
                                kfree(th, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        if (softc->quirks & CD_Q_BCD_TRACKS) {
                                /* we are going to have to convert the BCD
                                 * encoding on the cd to what is expected
                                 */
                                th->starting_track = 
                                        bcd2bin(th->starting_track);
                                th->ending_track = bcd2bin(th->ending_track);
                        }
                        th->len = ntohs(th->len);
                        bcopy(th, addr, sizeof(*th));
                        kfree(th, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOREADTOCENTRYS:
                {
                        struct cd_tocdata *data;
                        struct cd_toc_single *lead;
                        struct ioc_read_toc_entry *te =
                                (struct ioc_read_toc_entry *) addr;
                        struct ioc_toc_header *th;
                        u_int32_t len, readlen, idx, num;
                        u_int32_t starting_track = te->starting_track;

                        data = kmalloc(sizeof(*data), M_SCSICD, M_WAITOK);
                        lead = kmalloc(sizeof(*lead), M_SCSICD, M_WAITOK);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOREADTOCENTRYS\n"));

                        if (te->data_len < sizeof(struct cd_toc_entry)
                         || (te->data_len % sizeof(struct cd_toc_entry)) != 0
                         || (te->address_format != CD_MSF_FORMAT
                          && te->address_format != CD_LBA_FORMAT)) {
                                error = EINVAL;
                                kprintf("scsi_cd: error in readtocentries, "
                                       "returning EINVAL\n");
                                kfree(data, M_SCSICD);
                                kfree(lead, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }

                        th = &data->header;
                        error = cdreadtoc(periph, 0, 0, (u_int8_t *)th, 
                                          sizeof (*th), /*sense_flags*/0);
                        if (error) {
                                kfree(data, M_SCSICD);
                                kfree(lead, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }

                        if (softc->quirks & CD_Q_BCD_TRACKS) {
                                /* we are going to have to convert the BCD
                                 * encoding on the cd to what is expected
                                 */
                                th->starting_track =
                                    bcd2bin(th->starting_track);
                                th->ending_track = bcd2bin(th->ending_track);
                        }

                        if (starting_track == 0)
                                starting_track = th->starting_track;
                        else if (starting_track == LEADOUT)
                                starting_track = th->ending_track + 1;
                        else if (starting_track < th->starting_track ||
                                 starting_track > th->ending_track + 1) {
                                kprintf("scsi_cd: error in readtocentries, "
                                       "returning EINVAL\n");
                                kfree(data, M_SCSICD);
                                kfree(lead, M_SCSICD);
                                cam_periph_unlock(periph);
                                error = EINVAL;
                                break;
                        }

                        /* calculate reading length without leadout entry */
                        readlen = (th->ending_track - starting_track + 1) *
                                  sizeof(struct cd_toc_entry);

                        /* and with leadout entry */
                        len = readlen + sizeof(struct cd_toc_entry);
                        if (te->data_len < len) {
                                len = te->data_len;
                                if (readlen > len)
                                        readlen = len;
                        }
                        if (len > sizeof(data->entries)) {
                                kprintf("scsi_cd: error in readtocentries, "
                                       "returning EINVAL\n");
                                error = EINVAL;
                                kfree(data, M_SCSICD);
                                kfree(lead, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        num = len / sizeof(struct cd_toc_entry);

                        if (readlen > 0) {
                                error = cdreadtoc(periph, te->address_format,
                                                  starting_track,
                                                  (u_int8_t *)data,
                                                  readlen + sizeof (*th),
                                                  /*sense_flags*/0);
                                if (error) {
                                        kfree(data, M_SCSICD);
                                        kfree(lead, M_SCSICD);
                                        cam_periph_unlock(periph);
                                        break;
                                }
                        }

                        /* make leadout entry if needed */
                        idx = starting_track + num - 1;
                        if (softc->quirks & CD_Q_BCD_TRACKS)
                                th->ending_track = bcd2bin(th->ending_track);
                        if (idx == th->ending_track + 1) {
                                error = cdreadtoc(periph, te->address_format,
                                                  LEADOUT, (u_int8_t *)lead,
                                                  sizeof(*lead),
                                                  /*sense_flags*/0);
                                if (error) {
                                        kfree(data, M_SCSICD);
                                        kfree(lead, M_SCSICD);
                                        cam_periph_unlock(periph);
                                        break;
                                }
                                data->entries[idx - starting_track] = 
                                        lead->entry;
                        }
                        if (softc->quirks & CD_Q_BCD_TRACKS) {
                                for (idx = 0; idx < num - 1; idx++) {
                                        data->entries[idx].track =
                                            bcd2bin(data->entries[idx].track);
                                }
                        }

                        cam_periph_unlock(periph);
                        error = copyout(data->entries, te->data, len);
                        kfree(data, M_SCSICD);
                        kfree(lead, M_SCSICD);
                }
                break;
        case CDIOREADTOCENTRY:
                {
                        struct cd_toc_single *data;
                        struct ioc_read_toc_single_entry *te =
                                (struct ioc_read_toc_single_entry *) addr;
                        struct ioc_toc_header *th;
                        u_int32_t track;

                        data = kmalloc(sizeof(*data), M_SCSICD, M_WAITOK);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
                                  ("trying to do CDIOREADTOCENTRY\n"));

                        if (te->address_format != CD_MSF_FORMAT
                            && te->address_format != CD_LBA_FORMAT) {
                                kprintf("error in readtocentry, "
                                       " returning EINVAL\n");
                                kfree(data, M_SCSICD);
                                error = EINVAL;
                                cam_periph_unlock(periph);
                                break;
                        }

                        th = &data->header;
                        error = cdreadtoc(periph, 0, 0, (u_int8_t *)th,
                                          sizeof (*th), /*sense_flags*/0);
                        if (error) {
                                kfree(data, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }

                        if (softc->quirks & CD_Q_BCD_TRACKS) {
                                /* we are going to have to convert the BCD
                                 * encoding on the cd to what is expected
                                 */
                                th->starting_track =
                                    bcd2bin(th->starting_track);
                                th->ending_track = bcd2bin(th->ending_track);
                        }
                        track = te->track;
                        if (track == 0)
                                track = th->starting_track;
                        else if (track == LEADOUT)
                                /* OK */;
                        else if (track < th->starting_track ||
                                 track > th->ending_track + 1) {
                                kprintf("error in readtocentry, "
                                       " returning EINVAL\n");
                                kfree(data, M_SCSICD);
                                error = EINVAL;
                                cam_periph_unlock(periph);
                                break;
                        }

                        error = cdreadtoc(periph, te->address_format, track,
                                          (u_int8_t *)data, sizeof(*data),
                                          /*sense_flags*/0);
                        if (error) {
                                kfree(data, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }

                        if (softc->quirks & CD_Q_BCD_TRACKS)
                                data->entry.track = bcd2bin(data->entry.track);
                        bcopy(&data->entry, &te->entry,
                              sizeof(struct cd_toc_entry));
                        kfree(data, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCSETPATCH:
                {
                        struct ioc_patch *arg = (struct ioc_patch *)addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETPATCH\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = 
                                arg->patch[0];
                        page->audio.port[RIGHT_PORT].channels = 
                                arg->patch[1];
                        page->audio.port[2].channels = arg->patch[2];
                        page->audio.port[3].channels = arg->patch[3];
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCGETVOL:
                {
                        struct ioc_vol *arg = (struct ioc_vol *) addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCGETVOL\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        arg->vol[LEFT_PORT] = 
                                page->audio.port[LEFT_PORT].volume;
                        arg->vol[RIGHT_PORT] = 
                                page->audio.port[RIGHT_PORT].volume;
                        arg->vol[2] = page->audio.port[2].volume;
                        arg->vol[3] = page->audio.port[3].volume;
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCSETVOL:
                {
                        struct ioc_vol *arg = (struct ioc_vol *) addr;
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETVOL\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = CHANNEL_0;
                        page->audio.port[LEFT_PORT].volume = 
                                arg->vol[LEFT_PORT];
                        page->audio.port[RIGHT_PORT].channels = CHANNEL_1;
                        page->audio.port[RIGHT_PORT].volume = 
                                arg->vol[RIGHT_PORT];
                        page->audio.port[2].volume = arg->vol[2];
                        page->audio.port[3].volume = arg->vol[3];
                        error = cdsetmode(periph, &params);
                        cam_periph_unlock(periph);
                        kfree(params.mode_buf, M_SCSICD);
                }
                break;
        case CDIOCSETMONO:
                {
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETMONO\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = 
                                LEFT_CHANNEL | RIGHT_CHANNEL;
                        page->audio.port[RIGHT_PORT].channels = 
                                LEFT_CHANNEL | RIGHT_CHANNEL;
                        page->audio.port[2].channels = 0;
                        page->audio.port[3].channels = 0;
                        error = cdsetmode(periph, &params);
                        cam_periph_unlock(periph);
                        kfree(params.mode_buf, M_SCSICD);
                }
                break;
        case CDIOCSETSTEREO:
                {
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETSTEREO\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = 
                                LEFT_CHANNEL;
                        page->audio.port[RIGHT_PORT].channels = 
                                RIGHT_CHANNEL;
                        page->audio.port[2].channels = 0;
                        page->audio.port[3].channels = 0;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCSETMUTE:
                {
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETMUTE\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(&params, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = 0;
                        page->audio.port[RIGHT_PORT].channels = 0;
                        page->audio.port[2].channels = 0;
                        page->audio.port[3].channels = 0;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCSETLEFT:
                {
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE, 
                                  ("trying to do CDIOCSETLEFT\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = LEFT_CHANNEL;
                        page->audio.port[RIGHT_PORT].channels = LEFT_CHANNEL;
                        page->audio.port[2].channels = 0;
                        page->audio.port[3].channels = 0;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCSETRIGHT:
                {
                        struct cd_mode_params params;
                        union cd_pages *page;

                        params.alloc_len = sizeof(union cd_mode_data_6_10);
                        params.mode_buf = kmalloc(params.alloc_len, M_SCSICD,
                                                 M_WAITOK | M_ZERO);

                        cam_periph_lock(periph);
                        CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
                                  ("trying to do CDIOCSETRIGHT\n"));

                        error = cdgetmode(periph, &params, AUDIO_PAGE);
                        if (error) {
                                kfree(params.mode_buf, M_SCSICD);
                                cam_periph_unlock(periph);
                                break;
                        }
                        page = cdgetpage(&params);

                        page->audio.port[LEFT_PORT].channels = RIGHT_CHANNEL;
                        page->audio.port[RIGHT_PORT].channels = RIGHT_CHANNEL;
                        page->audio.port[2].channels = 0;
                        page->audio.port[3].channels = 0;
                        error = cdsetmode(periph, &params);
                        kfree(params.mode_buf, M_SCSICD);
                        cam_periph_unlock(periph);
                }
                break;
        case CDIOCRESUME:
                cam_periph_lock(periph);
                error = cdpause(periph, 1);
                cam_periph_unlock(periph);
                break;
        case CDIOCPAUSE:
                cam_periph_lock(periph);
                error = cdpause(periph, 0);
                cam_periph_unlock(periph);
                break;
        case CDIOCSTART:
                cam_periph_lock(periph);
                error = cdstartunit(periph, 0);
                cam_periph_unlock(periph);
                break;
        case CDIOCCLOSE:
                cam_periph_lock(periph);
                error = cdstartunit(periph, 1);
                cam_periph_unlock(periph);
                break;
        case CDIOCSTOP:
                cam_periph_lock(periph);
                error = cdstopunit(periph, 0);
                cam_periph_unlock(periph);
                break;
        case CDIOCEJECT:
                cam_periph_lock(periph);
                error = cdstopunit(periph, 1);
                cam_periph_unlock(periph);
                break;
        case CDIOCALLOW:
                cam_periph_lock(periph);
                cdprevent(periph, PR_ALLOW);
                cam_periph_unlock(periph);
                break;
        case CDIOCPREVENT:
                cam_periph_lock(periph);
                cdprevent(periph, PR_PREVENT);
                cam_periph_unlock(periph);
                break;
        case CDIOCSETDEBUG:
                /* sc_link->flags |= (SDEV_DB1 | SDEV_DB2); */
                error = ENOTTY;
                break;
        case CDIOCCLRDEBUG:
                /* sc_link->flags &= ~(SDEV_DB1 | SDEV_DB2); */
                error = ENOTTY;
                break;
        case CDIOCRESET:
                /* return (cd_reset(periph)); */
                error = ENOTTY;
                break;
        case CDRIOCREADSPEED:
                cam_periph_lock(periph);
                error = cdsetspeed(periph, *(u_int32_t *)addr, CDR_MAX_SPEED);
                cam_periph_unlock(periph);
                break;
        case CDRIOCWRITESPEED:
                cam_periph_lock(periph);
                error = cdsetspeed(periph, CDR_MAX_SPEED, *(u_int32_t *)addr);
                cam_periph_unlock(periph);
                break;
        case DVDIOCSENDKEY:
        case DVDIOCREPORTKEY: {
                struct dvd_authinfo *authinfo;

                authinfo = (struct dvd_authinfo *)addr;

                cam_periph_lock(periph);
                if (ap->a_cmd == DVDIOCREPORTKEY)
                        error = cdreportkey(periph, authinfo);
                else
                        error = cdsendkey(periph, authinfo);
                cam_periph_unlock(periph);
                break;
        }
        case DVDIOCREADSTRUCTURE: {
                struct dvd_struct *dvdstruct;

                dvdstruct = (struct dvd_struct *)addr;

                cam_periph_lock(periph);
                error = cdreaddvdstructure(periph, dvdstruct);
                cam_periph_unlock(periph);

                break;
        }
        default:
                cam_periph_lock(periph);
                error = cam_periph_ioctl(periph, ap->a_cmd, addr, cderror);
                cam_periph_unlock(periph);
                break;
        }

        cam_periph_lock(periph);
        cam_periph_unhold(periph);

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("leaving cdioctl\n"));

        cam_periph_unlock(periph);

        return (error);
}

static void
cdprevent(struct cam_periph *periph, int action)
{
        union   ccb *ccb;
        struct  cd_softc *softc;
        int     error;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdprevent\n"));

        softc = (struct cd_softc *)periph->softc;
        
        if (((action == PR_ALLOW)
          && (softc->flags & CD_FLAG_DISC_LOCKED) == 0)
         || ((action == PR_PREVENT)
          && (softc->flags & CD_FLAG_DISC_LOCKED) != 0)) {
                return;
        }
            
        ccb = cdgetccb(periph, /* priority */ 1);

        scsi_prevent(&ccb->csio, 
                     /*retries*/ 1,
                     cddone,
                     MSG_SIMPLE_Q_TAG,
                     action,
                     SSD_FULL_SIZE,
                     /* timeout */60000);
        
        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                        /*sense_flags*/SF_RETRY_UA|SF_NO_PRINT);

        xpt_release_ccb(ccb);

        if (error == 0) {
                if (action == PR_ALLOW)
                        softc->flags &= ~CD_FLAG_DISC_LOCKED;
                else
                        softc->flags |= CD_FLAG_DISC_LOCKED;
        }
}

int
cdcheckmedia(struct cam_periph *periph)
{
        struct cd_softc *softc;
        struct ioc_toc_header *toch;
        struct cd_toc_single leadout;
        struct ccb_getdev cgd;
        u_int32_t size, toclen;
        int error, num_entries, cdindex;
        int first_track_audio;
        struct disk_info info;

        softc = (struct cd_softc *)periph->softc;

        first_track_audio = -1;
        error = 0;

        cdprevent(periph, PR_PREVENT);

        /*
         * Set up disk info fields and tell the disk subsystem to reset
         * its internal copy of the label.
         */
        bzero(&info, sizeof(info));
        info.d_type = DTYPE_SCSI;
        info.d_dsflags &= ~DSO_COMPATLABEL;
        info.d_dsflags |= DSO_NOLABELS | DSO_COMPATPARTA;

        /*
         * Grab the inquiry data to get the vendor and product names.
         * Put them in the typename and packname for the label.
         */
        xpt_setup_ccb(&cgd.ccb_h, periph->path, /*priority*/ 1);
        cgd.ccb_h.func_code = XPT_GDEV_TYPE;
        xpt_action((union ccb *)&cgd);

#if 0
        strncpy(label->d_typename, cgd.inq_data.vendor,
                min(SID_VENDOR_SIZE, sizeof(label->d_typename)));
        strncpy(label->d_packname, cgd.inq_data.product,
                min(SID_PRODUCT_SIZE, sizeof(label->d_packname)));
#endif
        /*
         * Clear the valid media and TOC flags until we've verified that we
         * have both.
         */
        softc->flags &= ~(CD_FLAG_VALID_MEDIA|CD_FLAG_VALID_TOC);

        /*
         * Get the disc size and block size.  If we can't get it, we don't
         * have media, most likely.
         */
        if ((error = cdsize(periph, &size)) != 0) {
                /*
                 * Set a bogus sector size, so the slice code won't try to
                 * divide by 0 and panic the kernel.
                 */
                info.d_media_blksize = 2048;
                disk_setdiskinfo(&softc->disk, &info);

                /*
                 * XXX KDM is this a good idea?  Seems to cause more
                 * problems.
                 */
                if (softc->flags & CD_FLAG_OPEN) {
                        int force;

                        force = 1;

                        /*
                         * We don't bother checking the return value here,
                         * since we already have an error...
                         */
                        dsioctl(softc->disk.d_cdev, DIOCSYNCSLICEINFO,
                                /*data*/(caddr_t)&force, /*flags*/ 0,
                                &softc->disk.d_slice, &softc->disk.d_info);
                }

                /*
                 * Tell devstat(9) we don't have a blocksize.
                 */
                softc->device_stats.flags |= DEVSTAT_BS_UNAVAILABLE;

                cdprevent(periph, PR_ALLOW);

                return (error);
        } else {
                info.d_media_blksize = softc->params.blksize;
                info.d_media_blocks = softc->params.disksize;
                disk_setdiskinfo(&softc->disk, &info);

                /*
                 * Force a re-sync of slice information, like the blocksize,
                 * now that we know it.  It isn't pretty...but according to
                 * Bruce Evans, this is probably the best way to do it in
                 * -stable.  We only do this if we're already open, and
                 * therefore dsopen() has already run.  If CD_FLAG_OPEN
                 * isn't set, this isn't necessary.
                 */
                if (softc->flags & CD_FLAG_OPEN) {
                        int force;

                        force = 1;

                        error = dsioctl(softc->disk.d_cdev, DIOCSYNCSLICEINFO,
                                        /*data*/(caddr_t)&force, /*flags*/ 0,
                                        &softc->disk.d_slice,
                                        &softc->disk.d_info);
                        if (error != 0) {
                                /*
                                 * Set a bogus sector size, so the slice code
                                 * won't try to divide by 0 and panic the
                                 * kernel.
                                 */
                                info.d_media_blksize = 2048;
                                info.d_media_blocks = 0;
                                info.d_media_size = 0;
                                disk_setdiskinfo(&softc->disk, &info);

                                /*
                                 * Tell devstat(9) we don't have a blocksize.
                                 */
                                softc->device_stats.flags |=
                                        DEVSTAT_BS_UNAVAILABLE;

                                cdprevent(periph, PR_ALLOW);
                        }
                }

                /*
                 * We unconditionally (re)set the blocksize each time the
                 * CD device is opened.  This is because the CD can change,
                 * and therefore the blocksize might change.
                 * XXX problems here if some slice or partition is still
                 * open with the old size?
                 */
                if ((softc->device_stats.flags & DEVSTAT_BS_UNAVAILABLE) != 0)
                        softc->device_stats.flags &= ~DEVSTAT_BS_UNAVAILABLE;
                softc->device_stats.block_size = softc->params.blksize;

                softc->flags |= CD_FLAG_VALID_MEDIA;
        }

        /*
         * Now we check the table of contents.  This (currently) is only
         * used for the CDIOCPLAYTRACKS ioctl.  It may be used later to do
         * things like present a separate entry in /dev for each track,
         * like that acd(4) driver does.
         */
        bzero(&softc->toc, sizeof(softc->toc));
        toch = &softc->toc.header;

        /*
         * We will get errors here for media that doesn't have a table of
         * contents.  According to the MMC-3 spec: "When a Read TOC/PMA/ATIP
         * command is presented for a DDCD/CD-R/RW media, where the first TOC
         * has not been recorded (no complete session) and the Format codes
         * 0000b, 0001b, or 0010b are specified, this command shall be rejected
         * with an INVALID FIELD IN CDB.  Devices that are not capable of
         * reading an incomplete session on DDC/CD-R/RW media shall report
         * CANNOT READ MEDIUM - INCOMPATIBLE FORMAT."
         *
         * So this isn't fatal if we can't read the table of contents, it
         * just means that the user won't be able to issue the play tracks
         * ioctl, and likely lots of other stuff won't work either.  They
         * need to burn the CD before we can do a whole lot with it.  So
         * we don't print anything here if we get an error back.
         */
        error = cdreadtoc(periph, 0, 0, (u_int8_t *)toch, sizeof(*toch),
                          SF_NO_PRINT);
        /*
         * Errors in reading the table of contents aren't fatal, we just
         * won't have a valid table of contents cached.
         */
        if (error != 0) {
                error = 0;
                bzero(&softc->toc, sizeof(softc->toc));
                goto bailout;
        }

        if (softc->quirks & CD_Q_BCD_TRACKS) {
                toch->starting_track = bcd2bin(toch->starting_track);
                toch->ending_track = bcd2bin(toch->ending_track);
        }

        /* Number of TOC entries, plus leadout */
        num_entries = (toch->ending_track - toch->starting_track) + 2;

        if (num_entries <= 0)
                goto bailout;

        toclen = num_entries * sizeof(struct cd_toc_entry);

        error = cdreadtoc(periph, CD_MSF_FORMAT, toch->starting_track,
                          (u_int8_t *)&softc->toc, toclen + sizeof(*toch),
                          SF_NO_PRINT);
        if (error != 0) {
                error = 0;
                bzero(&softc->toc, sizeof(softc->toc));
                goto bailout;
        }

        if (softc->quirks & CD_Q_BCD_TRACKS) {
                toch->starting_track = bcd2bin(toch->starting_track);
                toch->ending_track = bcd2bin(toch->ending_track);
        }
        toch->len = scsi_2btoul((uint8_t *)&toch->len);

        /*
         * XXX KDM is this necessary?  Probably only if the drive doesn't
         * return leadout information with the table of contents.
         */
        cdindex = toch->starting_track + num_entries -1;
        if (cdindex == toch->ending_track + 1) {

                error = cdreadtoc(periph, CD_MSF_FORMAT, LEADOUT, 
                                  (u_int8_t *)&leadout, sizeof(leadout),
                                  SF_NO_PRINT);
                if (error != 0) {
                        error = 0;
                        goto bailout;
                }
                softc->toc.entries[cdindex - toch->starting_track] =
                        leadout.entry;
        }
        if (softc->quirks & CD_Q_BCD_TRACKS) {
                for (cdindex = 0; cdindex < (num_entries - 1); cdindex++) {
                        softc->toc.entries[cdindex].track =
                                bcd2bin(softc->toc.entries[cdindex].track);
                }
        }

        /*
         * Run through the TOC entries, find the first entry and determine
         * whether it is an audio or data track.
         */
        for (cdindex = 0; cdindex < (num_entries - 1); cdindex++) {
                if (softc->toc.entries[cdindex].track == toch->starting_track) {
                        if (softc->toc.entries[cdindex].control & 0x04)
                                first_track_audio = 0;
                        else
                                first_track_audio = 1;
                        break;
                }
        }

        /*
         * If first_track_audio is non-zero, we either have an error (e.g.
         * couldn't find the starting track) or the first track is an audio
         * track.  If first_track_audio is 0, the first track is a data
         * track that could have a disklabel.  Attempt to read the
         * disklabel off the media, just in case the user put one there.
         */
        if (first_track_audio == 0) {
                info.d_dsflags |= DSO_COMPATLABEL;
                info.d_dsflags &= ~DSO_NOLABELS;
                disk_setdiskinfo(&softc->disk, &info);
        }
        softc->flags |= CD_FLAG_VALID_TOC;

bailout:
        return (error);
}

static int
cdsize(struct cam_periph *periph, u_int32_t *size)
{
        struct cd_softc *softc;
        union ccb *ccb;
        struct scsi_read_capacity_data *rcap_buf;
        int error;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdsize\n"));

        softc = (struct cd_softc *)periph->softc;
             
        ccb = cdgetccb(periph, /* priority */ 1);

        rcap_buf = kmalloc(sizeof(struct scsi_read_capacity_data), 
                          M_SCSICD, M_INTWAIT | M_ZERO);

        scsi_read_capacity(&ccb->csio, 
                           /*retries*/ 1,
                           cddone,
                           MSG_SIMPLE_Q_TAG,
                           rcap_buf,
                           SSD_FULL_SIZE,
                           /* timeout */20000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA|SF_NO_PRINT);

        xpt_release_ccb(ccb);

        softc->params.disksize = scsi_4btoul(rcap_buf->addr) + 1;
        softc->params.blksize  = scsi_4btoul(rcap_buf->length);
        /*
         * SCSI-3 mandates that the reported blocksize shall be 2048.
         * Older drives sometimes report funny values, trim it down to
         * 2048, or other parts of the kernel will get confused.
         *
         * XXX we leave drives alone that might report 512 bytes, as
         * well as drives reporting more weird sizes like perhaps 4K.
         */
        if (softc->params.blksize > 2048 && softc->params.blksize <= 2352)
                softc->params.blksize = 2048;

        kfree(rcap_buf, M_SCSICD);
        *size = softc->params.disksize;

        return (error);

}

static int
cd6byteworkaround(union ccb *ccb)
{
        u_int8_t *cdb;
        struct cam_periph *periph;
        struct cd_softc *softc;
        struct cd_mode_params *params;
        int frozen, found;

        periph = xpt_path_periph(ccb->ccb_h.path);
        softc = (struct cd_softc *)periph->softc;

        cdb = ccb->csio.cdb_io.cdb_bytes;

        if ((ccb->ccb_h.flags & CAM_CDB_POINTER)
         || ((cdb[0] != MODE_SENSE_6)
          && (cdb[0] != MODE_SELECT_6)))
                return (0);

        /*
         * Because there is no convenient place to stash the overall
         * cd_mode_params structure pointer, we have to grab it like this.
         * This means that ALL MODE_SENSE and MODE_SELECT requests in the
         * cd(4) driver MUST go through cdgetmode() and cdsetmode()!
         *
         * XXX It would be nice if, at some point, we could increase the
         * number of available peripheral private pointers.  Both pointers
         * are currently used in most every peripheral driver.
         */
        found = 0;

        STAILQ_FOREACH(params, &softc->mode_queue, links) {
                if (params->mode_buf == ccb->csio.data_ptr) {
                        found = 1;
                        break;
                }
        }

        /*
         * This shouldn't happen.  All mode sense and mode select
         * operations in the cd(4) driver MUST go through cdgetmode() and
         * cdsetmode()!
         */
        if (found == 0) {
                xpt_print(periph->path,
                    "mode buffer not found in mode queue!\n");
                return (0);
        }

        params->cdb_size = 10;
        softc->minimum_command_size = 10;
        xpt_print(ccb->ccb_h.path,
            "%s(6) failed, increasing minimum CDB size to 10 bytes\n",
            (cdb[0] == MODE_SENSE_6) ? "MODE_SENSE" : "MODE_SELECT");

        if (cdb[0] == MODE_SENSE_6) {
                struct scsi_mode_sense_10 ms10;
                struct scsi_mode_sense_6 *ms6;
                int len;

                ms6 = (struct scsi_mode_sense_6 *)cdb;

                bzero(&ms10, sizeof(ms10));
                ms10.opcode = MODE_SENSE_10;
                ms10.byte2 = ms6->byte2;
                ms10.page = ms6->page;

                /*
                 * 10 byte mode header, block descriptor,
                 * sizeof(union cd_pages)
                 */
                len = sizeof(struct cd_mode_data_10);
                ccb->csio.dxfer_len = len;

                scsi_ulto2b(len, ms10.length);
                ms10.control = ms6->control;
                bcopy(&ms10, cdb, 10);
                ccb->csio.cdb_len = 10;
        } else {
                struct scsi_mode_select_10 ms10;
                struct scsi_mode_select_6 *ms6;
                struct scsi_mode_header_6 *header6;
                struct scsi_mode_header_10 *header10;
                struct scsi_mode_page_header *page_header;
                int blk_desc_len, page_num, page_size, len;

                ms6 = (struct scsi_mode_select_6 *)cdb;

                bzero(&ms10, sizeof(ms10));
                ms10.opcode = MODE_SELECT_10;
                ms10.byte2 = ms6->byte2;

                header6 = (struct scsi_mode_header_6 *)params->mode_buf;
                header10 = (struct scsi_mode_header_10 *)params->mode_buf;

                page_header = find_mode_page_6(header6);
                page_num = page_header->page_code;

                blk_desc_len = header6->blk_desc_len;

                page_size = cdgetpagesize(page_num);

                if (page_size != (page_header->page_length +
                    sizeof(*page_header)))
                        page_size = page_header->page_length +
                                sizeof(*page_header);

                len = sizeof(*header10) + blk_desc_len + page_size;

                len = min(params->alloc_len, len);

                /*
                 * Since the 6 byte parameter header is shorter than the 10
                 * byte parameter header, we need to copy the actual mode
                 * page data, and the block descriptor, if any, so things wind
                 * up in the right place.  The regions will overlap, but
                 * bcopy() does the right thing.
                 */
                bcopy(params->mode_buf + sizeof(*header6),
                      params->mode_buf + sizeof(*header10),
                      len - sizeof(*header10));

                /* Make sure these fields are set correctly. */
                scsi_ulto2b(0, header10->data_length);
                header10->medium_type = 0;
                scsi_ulto2b(blk_desc_len, header10->blk_desc_len);

                ccb->csio.dxfer_len = len;

                scsi_ulto2b(len, ms10.length);
                ms10.control = ms6->control;
                bcopy(&ms10, cdb, 10);
                ccb->csio.cdb_len = 10;
        }

        frozen = (ccb->ccb_h.status & CAM_DEV_QFRZN) != 0;
        ccb->ccb_h.status = CAM_REQUEUE_REQ;
        xpt_action(ccb);
        if (frozen) {
                cam_release_devq(ccb->ccb_h.path,
                                 /*relsim_flags*/0,
                                 /*openings*/0,
                                 /*timeout*/0,
                                 /*getcount_only*/0);
        }

        return (ERESTART);
}

static int
cderror(union ccb *ccb, u_int32_t cam_flags, u_int32_t sense_flags)
{
        struct cd_softc *softc;
        struct cam_periph *periph;
        int error;

        periph = xpt_path_periph(ccb->ccb_h.path);
        softc = (struct cd_softc *)periph->softc;

        error = 0;

        /*
         * We use a status of CAM_REQ_INVALID as shorthand -- if a 6 byte
         * CDB comes back with this particular error, try transforming it
         * into the 10 byte version.
         */
        if ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_INVALID) {
                error = cd6byteworkaround(ccb);
        } else if (((ccb->ccb_h.status & CAM_STATUS_MASK) ==
                     CAM_SCSI_STATUS_ERROR)
         && (ccb->ccb_h.status & CAM_AUTOSNS_VALID)
         && (ccb->csio.scsi_status == SCSI_STATUS_CHECK_COND)
         && ((ccb->ccb_h.flags & CAM_SENSE_PHYS) == 0)
         && ((ccb->ccb_h.flags & CAM_SENSE_PTR) == 0)) {
                int sense_key, error_code, asc, ascq;

                scsi_extract_sense(&ccb->csio.sense_data,
                                   &error_code, &sense_key, &asc, &ascq);
                if (sense_key == SSD_KEY_ILLEGAL_REQUEST)
                        error = cd6byteworkaround(ccb);
        }

        if (error == ERESTART)
                return (error);

        /*
         * XXX
         * Until we have a better way of doing pack validation,
         * don't treat UAs as errors.
         */
        sense_flags |= SF_RETRY_UA;
        return (cam_periph_error(ccb, cam_flags, sense_flags, 
                                 &softc->saved_ccb));
}

/*
 * Read table of contents
 */
static int 
cdreadtoc(struct cam_periph *periph, u_int32_t mode, u_int32_t start, 
          u_int8_t *data, u_int32_t len, u_int32_t sense_flags)
{
        struct scsi_read_toc *scsi_cmd;
        u_int32_t ntoc;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        ntoc = len;
        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        cam_fill_csio(csio, 
                      /* retries */ 1, 
                      /* cbfcnp */ cddone, 
                      /* flags */ CAM_DIR_IN,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ data,
                      /* dxfer_len */ len,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_read_toc),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_read_toc *)&csio->cdb_io.cdb_bytes;
        bzero (scsi_cmd, sizeof(*scsi_cmd));

        if (mode == CD_MSF_FORMAT)
                scsi_cmd->byte2 |= CD_MSF;
        scsi_cmd->from_track = start;
        /* scsi_ulto2b(ntoc, (u_int8_t *)scsi_cmd->data_len); */
        scsi_cmd->data_len[0] = (ntoc) >> 8;
        scsi_cmd->data_len[1] = (ntoc) & 0xff;

        scsi_cmd->op_code = READ_TOC;

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA | sense_flags);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdreadsubchannel(struct cam_periph *periph, u_int32_t mode, 
                 u_int32_t format, int track, 
                 struct cd_sub_channel_info *data, u_int32_t len) 
{
        struct scsi_read_subchannel *scsi_cmd;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        cam_fill_csio(csio, 
                      /* retries */ 1, 
                      /* cbfcnp */ cddone, 
                      /* flags */ CAM_DIR_IN,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ (u_int8_t *)data,
                      /* dxfer_len */ len,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_read_subchannel),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_read_subchannel *)&csio->cdb_io.cdb_bytes;
        bzero (scsi_cmd, sizeof(*scsi_cmd));

        scsi_cmd->op_code = READ_SUBCHANNEL;
        if (mode == CD_MSF_FORMAT)
                scsi_cmd->byte1 |= CD_MSF;
        scsi_cmd->byte2 = SRS_SUBQ;
        scsi_cmd->subchan_format = format;
        scsi_cmd->track = track;
        scsi_ulto2b(len, (u_int8_t *)scsi_cmd->data_len);
        scsi_cmd->control = 0;

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

/*
 * All MODE_SENSE requests in the cd(4) driver MUST go through this
 * routine.  See comments in cd6byteworkaround() for details.
 */
static int
cdgetmode(struct cam_periph *periph, struct cd_mode_params *data,
          u_int32_t page)
{
        struct ccb_scsiio *csio;
        struct cd_softc *softc;
        union ccb *ccb;
        int param_len;
        int error;

        softc = (struct cd_softc *)periph->softc;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        data->cdb_size = softc->minimum_command_size;
        if (data->cdb_size < 10)
                param_len = sizeof(struct cd_mode_data);
        else
                param_len = sizeof(struct cd_mode_data_10);

        /* Don't say we've got more room than we actually allocated */
        param_len = min(param_len, data->alloc_len);

        scsi_mode_sense_len(csio,
                            /* retries */ 1,
                            /* cbfcnp */ cddone,
                            /* tag_action */ MSG_SIMPLE_Q_TAG,
                            /* dbd */ 0,
                            /* page_code */ SMS_PAGE_CTRL_CURRENT,
                            /* page */ page,
                            /* param_buf */ data->mode_buf,
                            /* param_len */ param_len,
                            /* minimum_cmd_size */ softc->minimum_command_size,
                            /* sense_len */ SSD_FULL_SIZE,
                            /* timeout */ 50000);

        /*
         * It would be nice not to have to do this, but there's no
         * available pointer in the CCB that would allow us to stuff the
         * mode params structure in there and retrieve it in
         * cd6byteworkaround(), so we can set the cdb size.  The cdb size
         * lets the caller know what CDB size we ended up using, so they
         * can find the actual mode page offset.
         */
        STAILQ_INSERT_TAIL(&softc->mode_queue, data, links);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        STAILQ_REMOVE(&softc->mode_queue, data, cd_mode_params, links);

        /*
         * This is a bit of belt-and-suspenders checking, but if we run
         * into a situation where the target sends back multiple block
         * descriptors, we might not have enough space in the buffer to
         * see the whole mode page.  Better to return an error than
         * potentially access memory beyond our malloced region.
         */
        if (error == 0) {
                u_int32_t data_len;

                if (data->cdb_size == 10) {
                        struct scsi_mode_header_10 *hdr10;

                        hdr10 = (struct scsi_mode_header_10 *)data->mode_buf;
                        data_len = scsi_2btoul(hdr10->data_length);
                        data_len += sizeof(hdr10->data_length);
                } else {
                        struct scsi_mode_header_6 *hdr6;

                        hdr6 = (struct scsi_mode_header_6 *)data->mode_buf;
                        data_len = hdr6->data_length;
                        data_len += sizeof(hdr6->data_length);
                }

                /*
                 * Complain if there is more mode data available than we
                 * allocated space for.  This could potentially happen if
                 * we miscalculated the page length for some reason, if the
                 * drive returns multiple block descriptors, or if it sets
                 * the data length incorrectly.
                 */
                if (data_len > data->alloc_len) {
                        xpt_print(periph->path, "allocated modepage %d length "
                            "%d < returned length %d\n", page, data->alloc_len,
                            data_len);
                        error = ENOSPC;
                }
        }
        return (error);
}

/*
 * All MODE_SELECT requests in the cd(4) driver MUST go through this
 * routine.  See comments in cd6byteworkaround() for details.
 */
static int
cdsetmode(struct cam_periph *periph, struct cd_mode_params *data)
{
        struct ccb_scsiio *csio;
        struct cd_softc *softc;
        union ccb *ccb;
        int cdb_size, param_len;
        int error;

        softc = (struct cd_softc *)periph->softc;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        error = 0;

        /*
         * If the data is formatted for the 10 byte version of the mode
         * select parameter list, we need to use the 10 byte CDB.
         * Otherwise, we use whatever the stored minimum command size.
         */
        if (data->cdb_size == 10)
                cdb_size = data->cdb_size;
        else
                cdb_size = softc->minimum_command_size;

        if (cdb_size >= 10) {
                struct scsi_mode_header_10 *mode_header;
                u_int32_t data_len;

                mode_header = (struct scsi_mode_header_10 *)data->mode_buf;

                data_len = scsi_2btoul(mode_header->data_length);

                scsi_ulto2b(0, mode_header->data_length);
                /*
                 * SONY drives do not allow a mode select with a medium_type
                 * value that has just been returned by a mode sense; use a
                 * medium_type of 0 (Default) instead.
                 */
                mode_header->medium_type = 0;

                /*
                 * Pass back whatever the drive passed to us, plus the size
                 * of the data length field.
                 */
                param_len = data_len + sizeof(mode_header->data_length);

        } else {
                struct scsi_mode_header_6 *mode_header;

                mode_header = (struct scsi_mode_header_6 *)data->mode_buf;

                param_len = mode_header->data_length + 1;

                mode_header->data_length = 0;
                /*
                 * SONY drives do not allow a mode select with a medium_type
                 * value that has just been returned by a mode sense; use a
                 * medium_type of 0 (Default) instead.
                 */
                mode_header->medium_type = 0;
        }

        /* Don't say we've got more room than we actually allocated */
        param_len = min(param_len, data->alloc_len);

        scsi_mode_select_len(csio,
                             /* retries */ 1,
                             /* cbfcnp */ cddone,
                             /* tag_action */ MSG_SIMPLE_Q_TAG,
                             /* scsi_page_fmt */ 1,
                             /* save_pages */ 0,
                             /* param_buf */ data->mode_buf,
                             /* param_len */ param_len,
                             /* minimum_cmd_size */ cdb_size,
                             /* sense_len */ SSD_FULL_SIZE,
                             /* timeout */ 50000);

        /* See comments in cdgetmode() and cd6byteworkaround(). */
        STAILQ_INSERT_TAIL(&softc->mode_queue, data, links);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        STAILQ_REMOVE(&softc->mode_queue, data, cd_mode_params, links);

        return (error);
}

  

static int 
cdplay(struct cam_periph *periph, u_int32_t blk, u_int32_t len)
{
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;
        u_int8_t cdb_len;

        error = 0;
        ccb = cdgetccb(periph, /* priority */ 1);
        csio = &ccb->csio;
        /*
         * Use the smallest possible command to perform the operation.
         */
        if ((len & 0xffff0000) == 0) {
                /*
                 * We can fit in a 10 byte cdb.
                 */
                struct scsi_play_10 *scsi_cmd;

                scsi_cmd = (struct scsi_play_10 *)&csio->cdb_io.cdb_bytes;
                bzero (scsi_cmd, sizeof(*scsi_cmd));
                scsi_cmd->op_code = PLAY_10;
                scsi_ulto4b(blk, (u_int8_t *)scsi_cmd->blk_addr);
                scsi_ulto2b(len, (u_int8_t *)scsi_cmd->xfer_len);
                cdb_len = sizeof(*scsi_cmd);
        } else  {
                struct scsi_play_12 *scsi_cmd;

                scsi_cmd = (struct scsi_play_12 *)&csio->cdb_io.cdb_bytes;
                bzero (scsi_cmd, sizeof(*scsi_cmd));
                scsi_cmd->op_code = PLAY_12;
                scsi_ulto4b(blk, (u_int8_t *)scsi_cmd->blk_addr);
                scsi_ulto4b(len, (u_int8_t *)scsi_cmd->xfer_len);
                cdb_len = sizeof(*scsi_cmd);
        }
        cam_fill_csio(csio,
                      /*retries*/2,
                      cddone,
                      /*flags*/CAM_DIR_NONE,
                      MSG_SIMPLE_Q_TAG,
                      /*dataptr*/NULL,
                      /*datalen*/0,
                      /*sense_len*/SSD_FULL_SIZE,
                      cdb_len,
                      /*timeout*/50 * 1000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdplaymsf(struct cam_periph *periph, u_int32_t startm, u_int32_t starts,
          u_int32_t startf, u_int32_t endm, u_int32_t ends, u_int32_t endf)
{
        struct scsi_play_msf *scsi_cmd;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        cam_fill_csio(csio, 
                      /* retries */ 1, 
                      /* cbfcnp */ cddone, 
                      /* flags */ CAM_DIR_NONE,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ NULL,
                      /* dxfer_len */ 0,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_play_msf),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_play_msf *)&csio->cdb_io.cdb_bytes;
        bzero (scsi_cmd, sizeof(*scsi_cmd));

        scsi_cmd->op_code = PLAY_MSF;
        scsi_cmd->start_m = startm;
        scsi_cmd->start_s = starts;
        scsi_cmd->start_f = startf;
        scsi_cmd->end_m = endm;
        scsi_cmd->end_s = ends;
        scsi_cmd->end_f = endf; 

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);
        
        xpt_release_ccb(ccb);

        return(error);
}


static int
cdplaytracks(struct cam_periph *periph, u_int32_t strack, u_int32_t sindex,
             u_int32_t etrack, u_int32_t eindex)
{
        struct scsi_play_track *scsi_cmd;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        cam_fill_csio(csio, 
                      /* retries */ 1, 
                      /* cbfcnp */ cddone, 
                      /* flags */ CAM_DIR_NONE,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ NULL,
                      /* dxfer_len */ 0,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_play_track),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_play_track *)&csio->cdb_io.cdb_bytes;
        bzero (scsi_cmd, sizeof(*scsi_cmd));

        scsi_cmd->op_code = PLAY_TRACK;
        scsi_cmd->start_track = strack;
        scsi_cmd->start_index = sindex;
        scsi_cmd->end_track = etrack;
        scsi_cmd->end_index = eindex;

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdpause(struct cam_periph *periph, u_int32_t go)
{
        struct scsi_pause *scsi_cmd;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        csio = &ccb->csio;

        cam_fill_csio(csio, 
                      /* retries */ 1, 
                      /* cbfcnp */ cddone, 
                      /* flags */ CAM_DIR_NONE,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ NULL,
                      /* dxfer_len */ 0,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_pause),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_pause *)&csio->cdb_io.cdb_bytes;
        bzero (scsi_cmd, sizeof(*scsi_cmd));

        scsi_cmd->op_code = PAUSE;
        scsi_cmd->resume = go;

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdstartunit(struct cam_periph *periph, int load)
{
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        scsi_start_stop(&ccb->csio,
                        /* retries */ 1,
                        /* cbfcnp */ cddone,
                        /* tag_action */ MSG_SIMPLE_Q_TAG,
                        /* start */ TRUE,
                        /* load_eject */ load,
                        /* immediate */ FALSE,
                        /* sense_len */ SSD_FULL_SIZE,
                        /* timeout */ 50000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdstopunit(struct cam_periph *periph, u_int32_t eject)
{
        union ccb *ccb;
        int error;

        error = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        scsi_start_stop(&ccb->csio,
                        /* retries */ 1,
                        /* cbfcnp */ cddone,
                        /* tag_action */ MSG_SIMPLE_Q_TAG,
                        /* start */ FALSE,
                        /* load_eject */ eject,
                        /* immediate */ FALSE,
                        /* sense_len */ SSD_FULL_SIZE,
                        /* timeout */ 50000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdsetspeed(struct cam_periph *periph, u_int32_t rdspeed, u_int32_t wrspeed)
{
        struct scsi_set_speed *scsi_cmd;
        struct ccb_scsiio *csio;
        union ccb *ccb;
        int error;

        error = 0;
        ccb = cdgetccb(periph, /* priority */ 1);
        csio = &ccb->csio;

        /* Preserve old behavior: units in multiples of CDROM speed */
        if (rdspeed < 177)
                rdspeed *= 177;
        if (wrspeed < 177)
                wrspeed *= 177;

        cam_fill_csio(csio,
                      /* retries */ 1,
                      /* cbfcnp */ cddone,
                      /* flags */ CAM_DIR_NONE,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* data_ptr */ NULL,
                      /* dxfer_len */ 0,
                      /* sense_len */ SSD_FULL_SIZE,
                      sizeof(struct scsi_set_speed),
                      /* timeout */ 50000);

        scsi_cmd = (struct scsi_set_speed *)&csio->cdb_io.cdb_bytes;
        bzero(scsi_cmd, sizeof(*scsi_cmd));

        scsi_cmd->opcode = SET_CD_SPEED;
        scsi_ulto2b(rdspeed, scsi_cmd->readspeed);
        scsi_ulto2b(wrspeed, scsi_cmd->writespeed);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdreportkey(struct cam_periph *periph, struct dvd_authinfo *authinfo)
{
        union ccb *ccb;
        u_int8_t *databuf;
        u_int32_t lba;
        int error;
        int length;

        error = 0;
        databuf = NULL;
        lba = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        switch (authinfo->format) {
        case DVD_REPORT_AGID:
                length = sizeof(struct scsi_report_key_data_agid);
                break;
        case DVD_REPORT_CHALLENGE:
                length = sizeof(struct scsi_report_key_data_challenge);
                break;
        case DVD_REPORT_KEY1:
                length = sizeof(struct scsi_report_key_data_key1_key2);
                break;
        case DVD_REPORT_TITLE_KEY:
                length = sizeof(struct scsi_report_key_data_title);
                /* The lba field is only set for the title key */
                lba = authinfo->lba;
                break;
        case DVD_REPORT_ASF:
                length = sizeof(struct scsi_report_key_data_asf);
                break;
        case DVD_REPORT_RPC:
                length = sizeof(struct scsi_report_key_data_rpc);
                break;
        case DVD_INVALIDATE_AGID:
                length = 0;
                break;
        default:
                error = EINVAL;
                goto bailout;
                break; /* NOTREACHED */
        }

        if (length != 0) {
                databuf = kmalloc(length, M_DEVBUF, M_INTWAIT | M_ZERO);
        } else {
                databuf = NULL;
        }


        scsi_report_key(&ccb->csio,
                        /* retries */ 1,
                        /* cbfcnp */ cddone,
                        /* tag_action */ MSG_SIMPLE_Q_TAG,
                        /* lba */ lba,
                        /* agid */ authinfo->agid,
                        /* key_format */ authinfo->format,
                        /* data_ptr */ databuf,
                        /* dxfer_len */ length,
                        /* sense_len */ SSD_FULL_SIZE,
                        /* timeout */ 50000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        if (error != 0)
                goto bailout;

        if (ccb->csio.resid != 0) {
                xpt_print(periph->path, "warning, residual for report key "
                    "command is %d\n", ccb->csio.resid);
        }

        switch(authinfo->format) {
        case DVD_REPORT_AGID: {
                struct scsi_report_key_data_agid *agid_data;

                agid_data = (struct scsi_report_key_data_agid *)databuf;

                authinfo->agid = (agid_data->agid & RKD_AGID_MASK) >>
                        RKD_AGID_SHIFT;
                break;
        }
        case DVD_REPORT_CHALLENGE: {
                struct scsi_report_key_data_challenge *chal_data;

                chal_data = (struct scsi_report_key_data_challenge *)databuf;

                bcopy(chal_data->challenge_key, authinfo->keychal,
                      min(sizeof(chal_data->challenge_key),
                          sizeof(authinfo->keychal)));
                break;
        }
        case DVD_REPORT_KEY1: {
                struct scsi_report_key_data_key1_key2 *key1_data;

                key1_data = (struct scsi_report_key_data_key1_key2 *)databuf;

                bcopy(key1_data->key1, authinfo->keychal,
                      min(sizeof(key1_data->key1), sizeof(authinfo->keychal)));
                break;
        }
        case DVD_REPORT_TITLE_KEY: {
                struct scsi_report_key_data_title *title_data;

                title_data = (struct scsi_report_key_data_title *)databuf;

                authinfo->cpm = (title_data->byte0 & RKD_TITLE_CPM) >>
                        RKD_TITLE_CPM_SHIFT;
                authinfo->cp_sec = (title_data->byte0 & RKD_TITLE_CP_SEC) >>
                        RKD_TITLE_CP_SEC_SHIFT;
                authinfo->cgms = (title_data->byte0 & RKD_TITLE_CMGS_MASK) >>
                        RKD_TITLE_CMGS_SHIFT;
                bcopy(title_data->title_key, authinfo->keychal,
                      min(sizeof(title_data->title_key),
                          sizeof(authinfo->keychal)));
                break;
        }
        case DVD_REPORT_ASF: {
                struct scsi_report_key_data_asf *asf_data;

                asf_data = (struct scsi_report_key_data_asf *)databuf;

                authinfo->asf = asf_data->success & RKD_ASF_SUCCESS;
                break;
        }
        case DVD_REPORT_RPC: {
                struct scsi_report_key_data_rpc *rpc_data;

                rpc_data = (struct scsi_report_key_data_rpc *)databuf;

                authinfo->reg_type = (rpc_data->byte4 & RKD_RPC_TYPE_MASK) >>
                        RKD_RPC_TYPE_SHIFT;
                authinfo->vend_rsts =
                        (rpc_data->byte4 & RKD_RPC_VENDOR_RESET_MASK) >>
                        RKD_RPC_VENDOR_RESET_SHIFT;
                authinfo->user_rsts = rpc_data->byte4 & RKD_RPC_USER_RESET_MASK;
                authinfo->region = rpc_data->region_mask;
                authinfo->rpc_scheme = rpc_data->rpc_scheme1;
                break;
        }
        case DVD_INVALIDATE_AGID:
                break;
        default:
                /* This should be impossible, since we checked above */
                error = EINVAL;
                goto bailout;
                break; /* NOTREACHED */
        }
bailout:
        if (databuf != NULL)
                kfree(databuf, M_DEVBUF);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdsendkey(struct cam_periph *periph, struct dvd_authinfo *authinfo)
{
        union ccb *ccb;
        u_int8_t *databuf;
        int length;
        int error;

        error = 0;
        databuf = NULL;

        ccb = cdgetccb(periph, /* priority */ 1);

        switch(authinfo->format) {
        case DVD_SEND_CHALLENGE: {
                struct scsi_report_key_data_challenge *challenge_data;

                length = sizeof(*challenge_data);

                challenge_data = kmalloc(length, M_DEVBUF, M_INTWAIT | M_ZERO);

                databuf = (u_int8_t *)challenge_data;

                scsi_ulto2b(length - sizeof(challenge_data->data_len),
                            challenge_data->data_len);

                bcopy(authinfo->keychal, challenge_data->challenge_key,
                      min(sizeof(authinfo->keychal),
                          sizeof(challenge_data->challenge_key)));
                break;
        }
        case DVD_SEND_KEY2: {
                struct scsi_report_key_data_key1_key2 *key2_data;

                length = sizeof(*key2_data);

                key2_data = kmalloc(length, M_DEVBUF, M_INTWAIT | M_ZERO);

                databuf = (u_int8_t *)key2_data;

                scsi_ulto2b(length - sizeof(key2_data->data_len),
                            key2_data->data_len);

                bcopy(authinfo->keychal, key2_data->key1,
                      min(sizeof(authinfo->keychal), sizeof(key2_data->key1)));

                break;
        }
        case DVD_SEND_RPC: {
                struct scsi_send_key_data_rpc *rpc_data;

                length = sizeof(*rpc_data);

                rpc_data = kmalloc(length, M_DEVBUF, M_INTWAIT | M_ZERO);

                databuf = (u_int8_t *)rpc_data;

                scsi_ulto2b(length - sizeof(rpc_data->data_len),
                            rpc_data->data_len);

                rpc_data->region_code = authinfo->region;
                break;
        }
        default:
                error = EINVAL;
                goto bailout;
                break; /* NOTREACHED */
        }

        scsi_send_key(&ccb->csio,
                      /* retries */ 1,
                      /* cbfcnp */ cddone,
                      /* tag_action */ MSG_SIMPLE_Q_TAG,
                      /* agid */ authinfo->agid,
                      /* key_format */ authinfo->format,
                      /* data_ptr */ databuf,
                      /* dxfer_len */ length,
                      /* sense_len */ SSD_FULL_SIZE,
                      /* timeout */ 50000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

bailout:

        if (databuf != NULL)
                kfree(databuf, M_DEVBUF);

        xpt_release_ccb(ccb);

        return(error);
}

static int
cdreaddvdstructure(struct cam_periph *periph, struct dvd_struct *dvdstruct)
{
        union ccb *ccb;
        u_int8_t *databuf;
        u_int32_t address;
        int error;
        int length;

        error = 0;
        databuf = NULL;
        /* The address is reserved for many of the formats */
        address = 0;

        ccb = cdgetccb(periph, /* priority */ 1);

        switch(dvdstruct->format) {
        case DVD_STRUCT_PHYSICAL:
                length = sizeof(struct scsi_read_dvd_struct_data_physical);
                break;
        case DVD_STRUCT_COPYRIGHT:
                length = sizeof(struct scsi_read_dvd_struct_data_copyright);
                break;
        case DVD_STRUCT_DISCKEY:
                length = sizeof(struct scsi_read_dvd_struct_data_disc_key);
                break;
        case DVD_STRUCT_BCA:
                length = sizeof(struct scsi_read_dvd_struct_data_bca);
                break;
        case DVD_STRUCT_MANUFACT:
                length = sizeof(struct scsi_read_dvd_struct_data_manufacturer);
                break;
        case DVD_STRUCT_CMI:
                error = ENODEV;
                goto bailout;
#ifdef notyet
                length = sizeof(struct scsi_read_dvd_struct_data_copy_manage);
                address = dvdstruct->address;
#endif
                break; /* NOTREACHED */
        case DVD_STRUCT_PROTDISCID:
                length = sizeof(struct scsi_read_dvd_struct_data_prot_discid);
                break;
        case DVD_STRUCT_DISCKEYBLOCK:
                length = sizeof(struct scsi_read_dvd_struct_data_disc_key_blk);
                break;
        case DVD_STRUCT_DDS:
                length = sizeof(struct scsi_read_dvd_struct_data_dds);
                break;
        case DVD_STRUCT_MEDIUM_STAT:
                length = sizeof(struct scsi_read_dvd_struct_data_medium_status);
                break;
        case DVD_STRUCT_SPARE_AREA:
                length = sizeof(struct scsi_read_dvd_struct_data_spare_area);
                break;
        case DVD_STRUCT_RMD_LAST:
                error = ENODEV;
                goto bailout;
#ifdef notyet
                length = sizeof(struct scsi_read_dvd_struct_data_rmd_borderout);
                address = dvdstruct->address;
#endif
                break; /* NOTREACHED */
        case DVD_STRUCT_RMD_RMA:
                error = ENODEV;
                goto bailout;
#ifdef notyet
                length = sizeof(struct scsi_read_dvd_struct_data_rmd);
                address = dvdstruct->address;
#endif
                break; /* NOTREACHED */
        case DVD_STRUCT_PRERECORDED:
                length = sizeof(struct scsi_read_dvd_struct_data_leadin);
                break;
        case DVD_STRUCT_UNIQUEID:
                length = sizeof(struct scsi_read_dvd_struct_data_disc_id);
                break;
        case DVD_STRUCT_DCB:
                error = ENODEV;
                goto bailout;
#ifdef notyet
                length = sizeof(struct scsi_read_dvd_struct_data_dcb);
                address = dvdstruct->address;
#endif
                break; /* NOTREACHED */
        case DVD_STRUCT_LIST:
                /*
                 * This is the maximum allocation length for the READ DVD
                 * STRUCTURE command.  There's nothing in the MMC3 spec
                 * that indicates a limit in the amount of data that can
                 * be returned from this call, other than the limits
                 * imposed by the 2-byte length variables.
                 */
                length = 65535;
                break;
        default:
                error = EINVAL;
                goto bailout;
                break; /* NOTREACHED */
        }

        if (length != 0) {
                databuf = kmalloc(length, M_DEVBUF, M_INTWAIT | M_ZERO);
        } else {
                databuf = NULL;
        }

        scsi_read_dvd_structure(&ccb->csio,
                                /* retries */ 1,
                                /* cbfcnp */ cddone,
                                /* tag_action */ MSG_SIMPLE_Q_TAG,
                                /* lba */ address,
                                /* layer_number */ dvdstruct->layer_num,
                                /* key_format */ dvdstruct->format,
                                /* agid */ dvdstruct->agid,
                                /* data_ptr */ databuf,
                                /* dxfer_len */ length,
                                /* sense_len */ SSD_FULL_SIZE,
                                /* timeout */ 50000);

        error = cdrunccb(ccb, cderror, /*cam_flags*/CAM_RETRY_SELTO,
                         /*sense_flags*/SF_RETRY_UA);

        if (error != 0)
                goto bailout;

        switch(dvdstruct->format) {
        case DVD_STRUCT_PHYSICAL: {
                struct scsi_read_dvd_struct_data_layer_desc *inlayer;
                struct dvd_layer *outlayer;
                struct scsi_read_dvd_struct_data_physical *phys_data;

                phys_data =
                        (struct scsi_read_dvd_struct_data_physical *)databuf;
                inlayer = &phys_data->layer_desc;
                outlayer = (struct dvd_layer *)&dvdstruct->data;

                dvdstruct->length = sizeof(*inlayer);

                outlayer->book_type = (inlayer->book_type_version &
                        RDSD_BOOK_TYPE_MASK) >> RDSD_BOOK_TYPE_SHIFT;
                outlayer->book_version = (inlayer->book_type_version &
                        RDSD_BOOK_VERSION_MASK);
                outlayer->disc_size = (inlayer->disc_size_max_rate &
                        RDSD_DISC_SIZE_MASK) >> RDSD_DISC_SIZE_SHIFT;
                outlayer->max_rate = (inlayer->disc_size_max_rate &
                        RDSD_MAX_RATE_MASK);
                outlayer->nlayers = (inlayer->layer_info &
                        RDSD_NUM_LAYERS_MASK) >> RDSD_NUM_LAYERS_SHIFT;
                outlayer->track_path = (inlayer->layer_info &
                        RDSD_TRACK_PATH_MASK) >> RDSD_TRACK_PATH_SHIFT;
                outlayer->layer_type = (inlayer->layer_info &
                        RDSD_LAYER_TYPE_MASK);
                outlayer->linear_density = (inlayer->density &
                        RDSD_LIN_DENSITY_MASK) >> RDSD_LIN_DENSITY_SHIFT;
                outlayer->track_density = (inlayer->density &
                        RDSD_TRACK_DENSITY_MASK);
                outlayer->bca = (inlayer->bca & RDSD_BCA_MASK) >>
                        RDSD_BCA_SHIFT;
                outlayer->start_sector = scsi_3btoul(inlayer->main_data_start);
                outlayer->end_sector = scsi_3btoul(inlayer->main_data_end);
                outlayer->end_sector_l0 =
                        scsi_3btoul(inlayer->end_sector_layer0);
                break;
        }
        case DVD_STRUCT_COPYRIGHT: {
                struct scsi_read_dvd_struct_data_copyright *copy_data;

                copy_data = (struct scsi_read_dvd_struct_data_copyright *)
                        databuf;

                dvdstruct->cpst = copy_data->cps_type;
                dvdstruct->rmi = copy_data->region_info;
                dvdstruct->length = 0;

                break;
        }
        default:
                /*
                 * Tell the user what the overall length is, no matter
                 * what we can actually fit in the data buffer.
                 */
                dvdstruct->length = length - ccb->csio.resid - 
                        sizeof(struct scsi_read_dvd_struct_data_header);

                /*
                 * But only actually copy out the smaller of what we read
                 * in or what the structure can take.
                 */
                bcopy(databuf + sizeof(struct scsi_read_dvd_struct_data_header),
                      dvdstruct->data,
                      min(sizeof(dvdstruct->data), dvdstruct->length));
                break;
        }
bailout:

        if (databuf != NULL)
                kfree(databuf, M_DEVBUF);

        xpt_release_ccb(ccb);

        return(error);
}

void
scsi_report_key(struct ccb_scsiio *csio, u_int32_t retries,
                void (*cbfcnp)(struct cam_periph *, union ccb *),
                u_int8_t tag_action, u_int32_t lba, u_int8_t agid,
                u_int8_t key_format, u_int8_t *data_ptr, u_int32_t dxfer_len,
                u_int8_t sense_len, u_int32_t timeout)
{
        struct scsi_report_key *scsi_cmd;

        scsi_cmd = (struct scsi_report_key *)&csio->cdb_io.cdb_bytes;
        bzero(scsi_cmd, sizeof(*scsi_cmd));
        scsi_cmd->opcode = REPORT_KEY;
        scsi_ulto4b(lba, scsi_cmd->lba);
        scsi_ulto2b(dxfer_len, scsi_cmd->alloc_len);
        scsi_cmd->agid_keyformat = (agid << RK_KF_AGID_SHIFT) |
                (key_format & RK_KF_KEYFORMAT_MASK);

        cam_fill_csio(csio,
                      retries,
                      cbfcnp,
                      /*flags*/ (dxfer_len == 0) ? CAM_DIR_NONE : CAM_DIR_IN,
                      tag_action,
                      /*data_ptr*/ data_ptr,
                      /*dxfer_len*/ dxfer_len,
                      sense_len,
                      sizeof(*scsi_cmd),
                      timeout);
}

void
scsi_send_key(struct ccb_scsiio *csio, u_int32_t retries,
              void (*cbfcnp)(struct cam_periph *, union ccb *),
              u_int8_t tag_action, u_int8_t agid, u_int8_t key_format,
              u_int8_t *data_ptr, u_int32_t dxfer_len, u_int8_t sense_len,
              u_int32_t timeout)
{
        struct scsi_send_key *scsi_cmd;

        scsi_cmd = (struct scsi_send_key *)&csio->cdb_io.cdb_bytes;
        bzero(scsi_cmd, sizeof(*scsi_cmd));
        scsi_cmd->opcode = SEND_KEY;

        scsi_ulto2b(dxfer_len, scsi_cmd->param_len);
        scsi_cmd->agid_keyformat = (agid << RK_KF_AGID_SHIFT) |
                (key_format & RK_KF_KEYFORMAT_MASK);

        cam_fill_csio(csio,
                      retries,
                      cbfcnp,
                      /*flags*/ CAM_DIR_OUT,
                      tag_action,
                      /*data_ptr*/ data_ptr,
                      /*dxfer_len*/ dxfer_len,
                      sense_len,
                      sizeof(*scsi_cmd),
                      timeout);
}


void
scsi_read_dvd_structure(struct ccb_scsiio *csio, u_int32_t retries,
                        void (*cbfcnp)(struct cam_periph *, union ccb *),
                        u_int8_t tag_action, u_int32_t address,
                        u_int8_t layer_number, u_int8_t format, u_int8_t agid,
                        u_int8_t *data_ptr, u_int32_t dxfer_len,
                        u_int8_t sense_len, u_int32_t timeout)
{
        struct scsi_read_dvd_structure *scsi_cmd;

        scsi_cmd = (struct scsi_read_dvd_structure *)&csio->cdb_io.cdb_bytes;
        bzero(scsi_cmd, sizeof(*scsi_cmd));
        scsi_cmd->opcode = READ_DVD_STRUCTURE;

        scsi_ulto4b(address, scsi_cmd->address);
        scsi_cmd->layer_number = layer_number;
        scsi_cmd->format = format;
        scsi_ulto2b(dxfer_len, scsi_cmd->alloc_len);
        /* The AGID is the top two bits of this byte */
        scsi_cmd->agid = agid << 6;

        cam_fill_csio(csio,
                      retries,
                      cbfcnp,
                      /*flags*/ CAM_DIR_IN,
                      tag_action,
                      /*data_ptr*/ data_ptr,
                      /*dxfer_len*/ dxfer_len,
                      sense_len,
                      sizeof(*scsi_cmd),
                      timeout);
}