scsi_cd.c

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/*
 * Copyright (c) 1997 Justin T. Gibbs.
 * Copyright (c) 1997, 1998, 1999 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.
 *
 *      $Id: scsi_cd.c,v 1.14.2.5 1999/05/09 01:27:34 ken Exp $
 */
/*
 * Portions of this driver taken from the original FreeBSD cd driver.
 * Written by Julian Elischer ([e-mail])
 * 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 ([e-mail]) 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/systm.h>
#include <sys/kernel.h>
#include <sys/buf.h>
#include <sys/dkbad.h>
#include <sys/disklabel.h>
#include <sys/diskslice.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/cdio.h>
#include <sys/devicestat.h>
#include <sys/sysctl.h>

#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/cam_extend.h>
#include <cam/cam_periph.h>
#include <cam/cam_xpt_periph.h>
#include <cam/cam_queue.h>

#include <cam/scsi/scsi_message.h>
#include <cam/scsi/scsi_da.h>
#include <cam/scsi/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_quirks;

typedef enum {
	CD_FLAG_INVALID		= 0x001,
	CD_FLAG_NEW_DISC	= 0x002,
	CD_FLAG_DISC_LOCKED	= 0x004,
	CD_FLAG_DISC_REMOVABLE	= 0x008,
	CD_FLAG_TAGGED_QUEUING	= 0x010,
	CD_FLAG_OPEN		= 0x020,
	CD_FLAG_CHANGER		= 0x040,
	CD_FLAG_ACTIVE		= 0x080,
	CD_FLAG_SCHED_ON_COMP	= 0x100,
	CD_FLAG_RETRY_UA	= 0x200
} 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_bp ppriv_ptr1

typedef enum {
	CD_STATE_PROBE,
	CD_STATE_NORMAL
} cd_state;

struct cd_softc {
	cam_pinfo		pinfo;
	cd_state		state;
	volatile cd_flags	flags;
	struct buf_queue_head	buf_queue;
	LIST_HEAD(, ccb_hdr)	pending_ccbs;
	struct cd_params	params;
	struct diskslices 	*cd_slices;
	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;
};

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

/*
 * These 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.
 */
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-604X",
		  "*"}, /* quirks */ CD_Q_CHANGER
	},
	{
		{ T_CDROM, SIP_MEDIA_REMOVABLE, "CHINON", "CD-ROM CDS-535","*"},
		/* quirks */ CD_Q_BCD_TRACKS
	}
};

#ifndef MIN
#define MIN(x,y) ((x<y) ? x : y)
#endif

#define CD_CDEV_MAJOR 15
#define CD_BDEV_MAJOR 6

static	d_open_t	cdopen;
static	d_read_t	cdread;
static	d_close_t	cdclose;
static	d_ioctl_t	cdioctl;
static	d_strategy_t	cdstrategy;
static	d_strategy_t	cdstrategy1;

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	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	void		cdprevent(struct cam_periph *periph, int action);
static	int		cdsize(dev_t dev, u_int32_t *size);
static	int		cdreadtoc(struct cam_periph *periph, u_int32_t mode, 
				  u_int32_t start, struct cd_toc_entry *data, 
				  u_int32_t len);
static	int		cdgetmode(struct cam_periph *periph, 
				  struct cd_mode_data *data, u_int32_t page);
static	int		cdsetmode(struct cam_periph *periph,
				  struct cd_mode_data *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);

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

DATA_SET(periphdriver_set, cddriver);

/* For 2.2-stable support */
#ifndef D_DISK
#define D_DISK 0
#endif
static struct cdevsw cd_cdevsw = 
{
	/*d_open*/	cdopen,
	/*d_close*/	cdclose,
	/*d_read*/	cdread,
	/*d_write*/	nowrite,
	/*d_ioctl*/	cdioctl,
	/*d_stop*/	nostop,
	/*d_reset*/	noreset,
	/*d_devtotty*/	nodevtotty,
	/*d_poll*/	seltrue,
	/*d_mmap*/	nommap,
	/*d_strategy*/	cdstrategy,
	/*d_name*/	"cd",
	/*d_spare*/	NULL,
	/*d_maj*/	-1,
	/*d_dump*/	nodump,
	/*d_psize*/	nopsize,
	/*d_flags*/	D_DISK,
	/*d_maxio*/	0,
	/*b_maj*/	-1
};

static struct extend_array *cdperiphs;
static int num_changers;

#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;

/*
 * XXX KDM this CAM node should be moved if we ever get more CAM sysctl
 * variables.
 */
SYSCTL_NODE(_kern, OID_AUTO, cam, CTLFLAG_RD, 0, "CAM Subsystem");
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");
SYSCTL_INT(_kern_cam_cd_changer, OID_AUTO, max_busy_seconds, CTLFLAG_RW,
	   &changer_max_busy_seconds, 0, "Maximum changer scheduling quantum");

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_handle		 short_handle;
	struct callout_handle		 long_handle;
	volatile cd_changer_flags	 flags;
	STAILQ_ENTRY(cdchanger)		 changer_links;
	STAILQ_HEAD(chdevlist, cd_softc) chluns;
};

static STAILQ_HEAD(changerlist, cdchanger) changerq;

void
cdinit(void)
{
	cam_status status;
	struct cam_path *path;

	/*
	 * Create our extend array for storing the devices we attach to.
	 */
	cdperiphs = cam_extend_new();
	if (cdperiphs == NULL) {
		printf("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_create_path(&path, /*periph*/NULL, CAM_XPT_PATH_ID,
				 CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);

	if (status == CAM_REQ_CMP) {
		struct ccb_setasync csa;

                xpt_setup_ccb(&csa.ccb_h, path, /*priority*/5);
                csa.ccb_h.func_code = XPT_SASYNC_CB;
                csa.event_enable = AC_FOUND_DEVICE;
                csa.callback = cdasync;
                csa.callback_arg = NULL;
                xpt_action((union ccb *)&csa);
		status = csa.ccb_h.status;
                xpt_free_path(path);
        }

	if (status != CAM_REQ_CMP) {
		printf("cd: Failed to attach master async callback "
		       "due to status 0x%x!\n", status);
	} else {
		/* If we were successfull, register our devsw */
		cdevsw_add_generic(CD_BDEV_MAJOR, CD_CDEV_MAJOR, &cd_cdevsw);
	}
}

static void
cdoninvalidate(struct cam_periph *periph)
{
	int s;
	struct cd_softc *softc;
	struct buf *q_bp;
	struct ccb_setasync csa;

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

	/*
	 * De-register any async callbacks.
	 */
	xpt_setup_ccb(&csa.ccb_h, periph->path,
		      /* priority */ 5);
	csa.ccb_h.func_code = XPT_SASYNC_CB;
	csa.event_enable = 0;
	csa.callback = cdasync;
	csa.callback_arg = periph;
	xpt_action((union ccb *)&csa);

	softc->flags |= CD_FLAG_INVALID;

	/*
	 * Although the oninvalidate() routines are always called at
	 * splsoftcam, we need to be at splbio() here to keep the buffer
	 * queue from being modified while we traverse it.
	 */
	s = splbio();

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

	/*
	 * 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_path(periph->path);
	printf("lost device\n");
}

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

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

	xpt_print_path(periph->path);
	printf("removing device entry\n");

	s = splsoftcam();
	/*
	 * 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) {
			untimeout(cdshorttimeout, softc->changer,
				  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) {
			untimeout(cdrunchangerqueue, softc->changer,
				  softc->changer->long_handle);
			softc->changer->flags &= ~CHANGER_TIMEOUT_SCHED;
		}

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

		STAILQ_REMOVE(&changerq, softc->changer, cdchanger,
			      changer_links);
		xpt_print_path(periph->path);
		printf("removing changer entry\n");
		free(softc->changer, M_DEVBUF);