scsi_pass.c

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/*
 * Copyright (c) 1997, 1998 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_pass.c,v 1.5.2.3 1999/05/09 01:27:41 ken Exp $
 */

#include <sys/param.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/buf.h>
#include <sys/dkbad.h>
#include <sys/disklabel.h>
#include <sys/diskslice.h>
#include <sys/malloc.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/conf.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/devicestat.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_debug.h>

#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_message.h>
#include <cam/scsi/scsi_da.h>
#include <cam/scsi/scsi_pass.h>

typedef enum {
	PASS_FLAG_OPEN			= 0x01,
	PASS_FLAG_LOCKED		= 0x02,
	PASS_FLAG_INVALID		= 0x04
} pass_flags;

typedef enum {
	PASS_STATE_NORMAL
} pass_state;

typedef enum {
	PASS_CCB_BUFFER_IO,
	PASS_CCB_WAITING
} pass_ccb_types;

#define ccb_type	ppriv_field0
#define ccb_bp		ppriv_ptr1

struct pass_softc {
	pass_state	state;
	pass_flags	flags;
	u_int8_t	pd_type;
	struct		buf_queue_head buf_queue;
	union ccb	saved_ccb;
	struct devstat	device_stats;
#ifdef DEVFS
	void		*pass_devfs_token;
	void		*ctl_devfs_token;
#endif
};

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

#define PASS_CDEV_MAJOR 31

static	d_open_t	passopen;
static	d_read_t	passread;
static	d_write_t	passwrite;
static	d_close_t	passclose;
static	d_ioctl_t	passioctl;
static	d_strategy_t	passstrategy;

static	periph_init_t	passinit;
static	periph_ctor_t	passregister;
static	periph_oninv_t	passoninvalidate;
static	periph_dtor_t	passcleanup;
static	periph_start_t	passstart;
static	void		passasync(void *callback_arg, u_int32_t code,
				  struct cam_path *path, void *arg);
static	void		passdone(struct cam_periph *periph, 
				 union ccb *done_ccb);
static	int		passerror(union ccb *ccb, u_int32_t cam_flags, 
				  u_int32_t sense_flags);
static 	int		passsendccb(struct cam_periph *periph, union ccb *ccb,
				    union ccb *inccb);

static struct periph_driver passdriver =
{
	passinit, "pass",
	TAILQ_HEAD_INITIALIZER(passdriver.units), /* generation */ 0
};

DATA_SET(periphdriver_set, passdriver);

static struct cdevsw pass_cdevsw = 
{
	/*d_open*/	passopen,
	/*d_close*/	passclose,
	/*d_read*/	passread,
	/*d_write*/	passwrite,
	/*d_ioctl*/	passioctl,
	/*d_stop*/	nostop,
	/*d_reset*/	noreset,
	/*d_devtotty*/	nodevtotty,
	/*d_poll*/	seltrue,
	/*d_mmap*/	nommap,
	/*d_strategy*/	passstrategy,
	/*d_name*/	"pass",
	/*d_spare*/	NULL,
	/*d_maj*/	-1,
	/*d_dump*/	nodump,
	/*d_psize*/	nopsize,
	/*d_flags*/	0,
	/*d_maxio*/	0,
	/*b_maj*/	-1
};

static struct extend_array *passperiphs;

static void
passinit(void)
{
	cam_status status;
	struct cam_path *path;

	/*
	 * Create our extend array for storing the devices we attach to.
	 */
	passperiphs = cam_extend_new();
	if (passperiphs == NULL) {
		printf("passm: 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 = passasync;
                csa.callback_arg = NULL;
                xpt_action((union ccb *)&csa);
		status = csa.ccb_h.status;
                xpt_free_path(path);
        }

	if (status != CAM_REQ_CMP) {
		printf("pass: Failed to attach master async callback "
		       "due to status 0x%x!\n", status);
	} else {
		dev_t dev;

		/* If we were successfull, register our devsw */
		dev = makedev(PASS_CDEV_MAJOR, 0);
		cdevsw_add(&dev, &pass_cdevsw, NULL);
	}
	
}

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

	softc = (struct pass_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 = passasync;
	csa.callback_arg = periph;
	xpt_action((union ccb *)&csa);

	softc->flags |= PASS_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 (bootverbose) {
		xpt_print_path(periph->path);
		printf("lost device\n");
	}

}

static void
passcleanup(struct cam_periph *periph)
{
	struct pass_softc *softc;

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

	devstat_remove_entry(&softc->device_stats);

	cam_extend_release(passperiphs, periph->unit_number);

	if (bootverbose) {
		xpt_print_path(periph->path);
		printf("removing device entry\n");
	}
	free(softc, M_DEVBUF);
}

static void
passasync(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;

		/*
		 * Allocate a peripheral instance for
		 * this device and start the probe
		 * process.
		 */
		status = cam_periph_alloc(passregister, passoninvalidate,
					  passcleanup, passstart, "pass",
					  CAM_PERIPH_BIO, cgd->ccb_h.path,
					  passasync, AC_FOUND_DEVICE, cgd);

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

		break;
	}
	case AC_LOST_DEVICE:
		cam_periph_invalidate(periph);
		break;
	case AC_TRANSFER_NEG:
	case AC_SENT_BDR:
	case AC_SCSI_AEN:
	case AC_UNSOL_RESEL:
	case AC_BUS_RESET:
	default:
		break;
	}
}

static cam_status
passregister(struct cam_periph *periph, void *arg)
{
	struct pass_softc *softc;
	struct ccb_setasync csa;
	struct ccb_getdev *cgd;

	cgd = (struct ccb_getdev *)arg;
	if (periph == NULL) {
		printf("passregister: periph was NULL!!\n");
		return(CAM_REQ_CMP_ERR);
	}

	if (cgd == NULL) {
		printf("passregister: no getdev CCB, can't register device\n");
		return(CAM_REQ_CMP_ERR);
	}

	softc = (struct pass_softc *)malloc(sizeof(*softc),
					    M_DEVBUF, M_NOWAIT);

	if (softc == NULL) {
		printf("passregister: Unable to probe new device. "
		       "Unable to allocate softc\n");				
		return(CAM_REQ_CMP_ERR);
	}

	bzero(softc, sizeof(*softc));
	softc->state = PASS_STATE_NORMAL;
	softc->pd_type = cgd->pd_type;
	bufq_init(&softc->buf_queue);

	periph->softc = softc;

	cam_extend_set(passperiphs, periph->unit_number, periph);
	/*
	 * We pass in 0 for a blocksize, since we don't 
	 * know what the blocksize of this device is, if 
	 * it even has a blocksize.
	 */
	devstat_add_entry(&softc->device_stats, "pass", periph->unit_number,
			  0, DEVSTAT_NO_BLOCKSIZE | DEVSTAT_NO_ORDERED_TAGS,
			  cgd->pd_type |
			  DEVSTAT_TYPE_IF_SCSI |
			  DEVSTAT_TYPE_PASS,
			  DEVSTAT_PRIORITY_PASS);
	/*
	 * Add an async callback so that we get
	 * notified if this device goes away.
	 */
	xpt_setup_ccb(&csa.ccb_h, periph->path, /* priority */ 5);
	csa.ccb_h.func_code = XPT_SASYNC_CB;
	csa.event_enable = AC_LOST_DEVICE;
	csa.callback = passasync;
	csa.callback_arg = periph;
	xpt_action((union ccb *)&csa);

	if (bootverbose)
		xpt_announce_periph(periph, NULL);

	return(CAM_REQ_CMP);
}

static int
passopen(dev_t dev, int flags, int fmt, struct proc *p)
{
	struct cam_periph *periph;
	struct pass_softc *softc;
	int unit, error;
	int s;

	error = 0; /* default to no error */

	/* unit = dkunit(dev); */
	/* XXX KDM fix this */
	unit = minor(dev) & 0xff;

	periph = cam_extend_get(passperiphs, unit);

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

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

	s = splsoftcam();
	if (softc->flags & PASS_FLAG_INVALID) {
		splx(s);
		return(ENXIO);
	}

	/*
	 * Don't allow access when we're running at a high securelvel.
	 */
	if (securelevel > 1) {
		splx(s);
		return(EPERM);
	}

	/*
	 * Only allow read-write access.
	 */
	if (((flags & FWRITE) == 0) || ((flags & FREAD) == 0)) {
		splx(s);
		return(EPERM);
	}

	/*
	 * We don't allow nonblocking access.
	 */
	if ((flags & O_NONBLOCK) != 0) {
		xpt_print_path(periph->path);
		printf("can't do nonblocking accesss\n");
		splx(s);
		return(EINVAL);
	}

	if ((error = cam_periph_lock(periph, PRIBIO | PCATCH)) != 0) {
		splx(s);