Add the ability to use ATAPI devices via CAM.

The CAM<>ATAPI layer was submitted by "Thomas Quinot <thomas@cuivre.fr.eu.org>"
changes form the version on the net by me (formatting, ability to be used
alone without the ATAPI native device driver, proper speed reporting...)

See /sys/conf/NOTES for usage.

Submitted by: Thomas Quinot <thomas@cuivre.fr.eu.org>

1 files changed, 712 insertions, 0 deletions

diff --git a/sys/dev/ata/atapi-cam.c b/sys/dev/ata/atapi-cam.c
new file mode 100644
index 0000000..eb14d41
--- /dev/null
+++ b/sys/dev/ata/atapi-cam.c
@@ -0,0 +1,712 @@
+/*-
+ * Copyright (c) 2001,2002 Thomas Quinot <thomas@cuivre.fr.eu.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer,
+ *    without modification, immediately at the beginning of the file.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/devicestat.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/ata.h>
+#include <machine/bus.h>
+
+#include <cam/cam.h>
+#include <cam/cam_ccb.h>
+#include <cam/cam_periph.h>
+#include <cam/cam_sim.h>
+#include <cam/cam_xpt_sim.h>
+#include <cam/cam_debug.h>
+#include <cam/scsi/scsi_all.h>
+
+#include <dev/ata/ata-all.h>
+#include <dev/ata/atapi-all.h>
+
+/* hardware command descriptor block */
+struct atapi_hcb {
+    struct atapi_xpt_softc *softc;
+    int			unit;
+    int			bus;
+    int			target;
+    int			lun;
+    union ccb		*ccb;
+    u_int8_t		cmd[CAM_MAX_CDBLEN];
+    int			lags;
+#define DOING_AUTOSENSE 1
+
+    char		*dxfer_alloc;
+    TAILQ_ENTRY(atapi_hcb) chain;
+};
+
+/* private data associated with an ATA bus */
+struct atapi_xpt_softc {
+    struct ata_channel	*ata_ch;
+    struct cam_path	*path;
+    struct cam_sim	*sim;
+    int			flags;
+#define BUS_REGISTERED		0x01
+#define RESOURCE_SHORTAGE	0x02
+
+    TAILQ_HEAD(,atapi_hcb) pending_hcbs;
+    LIST_ENTRY(atapi_xpt_softc) chain;
+};
+
+static LIST_HEAD(,atapi_xpt_softc) all_buses = LIST_HEAD_INITIALIZER(all_buses);
+
+/* CAM XPT methods */
+static void atapi_action(struct cam_sim *, union ccb *);
+static void atapi_action1(struct cam_sim *, union ccb *);
+static void atapi_poll(struct cam_sim *);
+static void atapi_async(void *, u_int32_t, struct cam_path *, void *);
+static void atapi_async1(void *, u_int32_t, struct cam_path *, void *);
+static int atapi_cb(struct atapi_request *);
+
+/* internal functions */
+static void setup_dev(struct atapi_xpt_softc *, struct ata_device *);
+static void setup_async_cb(struct atapi_xpt_softc *, uint32_t);
+static void cam_rescan_callback(struct cam_periph *, union ccb *);
+static void cam_rescan(struct cam_sim *);
+static void free_hcb_and_ccb_done(struct atapi_hcb *, u_int32_t);
+static struct atapi_hcb *allocate_hcb(struct atapi_xpt_softc *, int, int, union ccb *);
+static void free_hcb(struct atapi_hcb *hcb);
+static void free_softc(struct atapi_xpt_softc *scp);
+static struct ata_device *get_ata_device(struct atapi_xpt_softc *scp, int id);
+
+static MALLOC_DEFINE(M_ATACAM, "ATA CAM transport", "ATA driver CAM-XPT layer");
+
+void 
+atapi_cam_attach_bus(struct ata_channel *ata_ch)
+{
+    struct atapi_xpt_softc *scp = NULL;
+    struct cam_devq *devq = NULL;
+    struct cam_sim *sim = NULL;
+    struct cam_path *path = NULL;
+    int unit;
+
+    LIST_FOREACH(scp, &all_buses, chain) {
+	if (scp->ata_ch == ata_ch)
+	    return;
+    }
+
+    if ((scp = malloc(sizeof(struct atapi_xpt_softc),
+		      M_ATACAM, M_NOWAIT | M_ZERO)) == NULL)
+	goto error;
+
+    scp->ata_ch = ata_ch;
+    TAILQ_INIT(&scp->pending_hcbs);
+    LIST_INSERT_HEAD(&all_buses, scp, chain);
+    unit = device_get_unit(ata_ch->dev);
+
+    if ((devq = cam_simq_alloc(16)) == NULL)
+	goto error;
+
+    if ((sim = cam_sim_alloc(atapi_action, atapi_poll, "ata",
+		 (void *)scp, unit, 1, 1, devq)) == NULL) {
+	cam_simq_free(devq);
+	goto error;
+    }
+    scp->sim = sim;
+
+    if (xpt_bus_register(sim, 0) != CAM_SUCCESS) {
+	goto error;
+    }
+    scp->flags |= BUS_REGISTERED;
+
+    if (xpt_create_path(&path, /*periph*/ NULL,
+		cam_sim_path(sim), CAM_TARGET_WILDCARD,
+		CAM_LUN_WILDCARD) != CAM_REQ_CMP) {
+	goto error;
+    }
+    scp->path = path;
+
+#ifdef CAMDEBUG
+    xpt_print_path(path);
+    printf("Registered SIM for ata%d\n", unit);
+#endif
+
+    setup_async_cb(scp, AC_LOST_DEVICE);
+
+    if (ata_ch->devices & ATA_ATAPI_MASTER)
+	setup_dev(scp, &ata_ch->device[MASTER]);
+    if (ata_ch->devices & ATA_ATAPI_SLAVE)
+	setup_dev(scp, &ata_ch->device[SLAVE]);
+
+    cam_rescan(sim);
+    return;
+
+error:
+    free_softc(scp);
+}
+
+void 
+atapi_cam_detach_bus(struct ata_channel *ata_ch)
+{
+    struct atapi_xpt_softc *scp;
+
+    LIST_FOREACH(scp, &all_buses, chain) {
+	if (scp->ata_ch == ata_ch)
+	    free_softc(scp);
+    }
+}
+
+static void
+setup_dev(struct atapi_xpt_softc *scp, struct ata_device *atp)
+{
+    if (atp->driver == NULL) {
+	ata_set_name(atp, "atapicam",
+		     2 * device_get_unit(atp->channel->dev) +
+		     (atp->unit == ATA_MASTER) ? 0 : 1);
+	atp->driver = (void *)scp;
+    }
+}
+
+static void
+setup_async_cb(struct atapi_xpt_softc *scp, uint32_t events)
+{
+    struct ccb_setasync csa;
+
+    xpt_setup_ccb(&csa.ccb_h, scp->path, /*priority*/ 5);
+    csa.ccb_h.func_code = XPT_SASYNC_CB;
+    csa.event_enable = events;
+    csa.callback = &atapi_async;
+    csa.callback_arg = scp->sim;
+    xpt_action((union ccb *) &csa);
+}
+
+static void 
+atapi_action(struct cam_sim *sim, union ccb *ccb)
+{
+    int s = splcam();
+
+    atapi_action1(sim, ccb);
+    splx(s);
+}
+
+static void 
+atapi_action1(struct cam_sim *sim, union ccb *ccb)
+{
+    struct atapi_xpt_softc *softc = (struct atapi_xpt_softc*)cam_sim_softc(sim);
+    struct ccb_hdr *ccb_h = &ccb->ccb_h;
+    struct atapi_hcb *hcb = NULL;
+    int unit = cam_sim_unit(sim);
+    int bus = cam_sim_bus(sim);
+    int len;
+    char *buf;
+
+    switch (ccb_h->func_code) {
+    case XPT_PATH_INQ: {
+	struct ccb_pathinq *cpi = &ccb->cpi;
+
+	cpi->version_num = 1;
+	cpi->hba_inquiry = 0;
+	cpi->hba_misc = 0;
+	cpi->hba_eng_cnt = 0;
+	bzero(cpi->vuhba_flags, sizeof(cpi->vuhba_flags));
+	cpi->max_target = 1;
+	cpi->max_lun = 7;
+	cpi->async_flags = 0;
+	cpi->hpath_id = 0;
+	cpi->initiator_id = 7;
+	strncpy(cpi->sim_vid, "ATAPI-SIM", sizeof(cpi->sim_vid));
+	strncpy(cpi->hba_vid, "ATAPI", sizeof(cpi->hba_vid));
+	strncpy(cpi->dev_name, cam_sim_name(sim), sizeof cpi->dev_name);
+	cpi->unit_number = cam_sim_unit(sim);
+	cpi->bus_id = cam_sim_bus(sim);
+	if (softc->ata_ch && ccb_h->target_id >= 0) {
+	    switch (softc->ata_ch->device[ccb_h->target_id].mode) {
+	    case ATA_PIO1:
+		cpi->base_transfer_speed = 5200;
+		break;
+	    case ATA_PIO2:
+		cpi->base_transfer_speed = 7000;
+		break;
+	    case ATA_PIO3:
+		cpi->base_transfer_speed = 11000;
+		break;
+	    case ATA_PIO4:
+	    case ATA_DMA:
+	    case ATA_WDMA2:
+		cpi->base_transfer_speed = 16000;
+		break;
+	    case ATA_UDMA2:
+		cpi->base_transfer_speed = 33000;
+		break;
+	    case ATA_UDMA4:
+		cpi->base_transfer_speed = 66000;
+		break;
+	    case ATA_UDMA5:
+		cpi->base_transfer_speed = 100000;
+		break;
+	    case ATA_UDMA6:
+		cpi->base_transfer_speed = 133000;
+		break;
+	    default: cpi->base_transfer_speed = 3300;
+	    }
+	}
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+    }
+
+    case XPT_RESET_DEV:
+	/* should reset the device */
+#ifdef CAMDEBUG
+	xpt_print_path(ccb->ccb_h.path);
+	printf("dev reset");
+#endif
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+
+    case XPT_RESET_BUS:
+	/* should reset the ATA bus */
+#ifdef CAMDEBUG
+	xpt_print_path(ccb->ccb_h.path);
+	printf("bus reset");
+#endif
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+
+    case XPT_SET_TRAN_SETTINGS:
+	/* ignore these, we're not doing SCSI here */
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+
+    case XPT_GET_TRAN_SETTINGS: {
+	struct ccb_trans_settings *cts = &ccb->cts;
+
+	cts->flags |=
+	    (CCB_TRANS_SYNC_RATE_VALID | CCB_TRANS_SYNC_OFFSET_VALID |
+	     CCB_TRANS_BUS_WIDTH_VALID | CCB_TRANS_DISC_VALID |
+	     CCB_TRANS_TQ_VALID);
+	cts->flags &= ~(CCB_TRANS_DISC_ENB | CCB_TRANS_TAG_ENB);
+	cts->sync_period = 0;
+	cts->sync_offset = 0;
+	cts->bus_width = 8;
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+    }
+
+    case XPT_CALC_GEOMETRY: {
+	struct ccb_calc_geometry *ccg;
+	unsigned int size_mb;
+	unsigned int secs_per_cylinder;
+	int extended;
+
+	ccg = &ccb->ccg;
+	size_mb = ccg->volume_size / ((1024L * 1024L) / ccg->block_size);
+	extended = 1;
+
+	if (size_mb > 1024 && extended) {
+	    ccg->heads = 255;
+	    ccg->secs_per_track = 63;
+	} else {
+	    ccg->heads = 64;
+	    ccg->secs_per_track = 32;
+	}
+	secs_per_cylinder = ccg->heads * ccg->secs_per_track;
+	ccg->cylinders = ccg->volume_size / secs_per_cylinder;
+	ccb->ccb_h.status = CAM_REQ_CMP;
+	xpt_done(ccb);
+	return;
+    }
+
+    case XPT_SCSI_IO: {
+	struct ccb_scsiio *csio = &ccb->csio;
+	int tid = ccb_h->target_id, lid = ccb_h->target_lun;
+	struct ata_device *dev = get_ata_device(softc, tid);
+
+#ifdef CAMDEBUG
+	char cdb_str[(SCSI_MAX_CDBLEN * 3) + 1];
+
+	printf("XPT_SCSI_IO (b%d u%d t%d l%d)\n", bus, unit, tid, lid);
+#endif
+	/* check that this request was not aborted already */
+	if ((ccb_h->status & CAM_STATUS_MASK) != CAM_REQ_INPROG) {
+#ifdef CAMDEBUG
+	    printf("Already in progress\n");
+#endif
+	    xpt_done(ccb);
+	    return;
+	}
+	if (dev == NULL) {
+#ifdef CAMDEBUG
+	    printf("Invalid target %d\n", tid);
+#endif
+	    ccb_h->status = CAM_TID_INVALID;
+	    xpt_done(ccb);
+	    return;
+	}
+	if (lid > 0) {
+#ifdef CAMDEBUG
+	    printf("Invalid LUN %d\n", lid);
+#endif
+	    ccb_h->status = CAM_LUN_INVALID;
+	    xpt_done(ccb);
+	    return;
+	}
+	if ((ccb_h->flags & CAM_SCATTER_VALID)) {
+	    /* scatter-gather not supported */
+	    xpt_print_path(ccb_h->path);
+	    printf("ATAPI-CAM does not support scatter-gather yet!\n");
+	    break;
+	}
+	if ((hcb = allocate_hcb(softc, unit, bus, ccb)) == NULL)
+	    goto action_oom;
+
+	ccb_h->status |= CAM_SIM_QUEUED;
+
+	bcopy((ccb_h->flags & CAM_CDB_POINTER) ?
+	      csio->cdb_io.cdb_ptr : csio->cdb_io.cdb_bytes,
+	      hcb->cmd, csio->cdb_len);
+#ifdef CAMDEBUG
+	printf("hcb@%p: %s\n",
+	       hcb, scsi_cdb_string(hcb->cmd, cdb_str, sizeof(cdb_str)));
+#endif
+
+	len = csio->dxfer_len;
+	buf = csio->data_ptr;
+
+	/* some SCSI commands require special processing */
+	switch (hcb->cmd[0]) {
+	case INQUIRY: {
+	    /*
+	     * many ATAPI devices seem to report more than
+	     * SHORT_INQUIRY_LENGTH bytes of available INQUIRY
+	     * information, but respond with some incorrect condition
+	     * when actually asked for it, so we are going to pretend
+	     * that only SHORT_INQUIRY_LENGTH are expected, anyway.
+	     */
+	    struct scsi_inquiry *inq = (struct scsi_inquiry *) &hcb->cmd[0];
+
+	    if (inq->byte2 == 0 && inq->page_code == 0 &&
+		inq->length > SHORT_INQUIRY_LENGTH) {
+		bzero(buf, len);
+		len = inq->length = SHORT_INQUIRY_LENGTH;
+	    }
+	    break;
+	}
+	case MODE_SELECT_6:
+	    /* FALLTHROUGH */
+
+	case MODE_SENSE_6:
+	    /*
+	     * not supported by ATAPI/MMC devices (per SCSI MMC spec)
+	     * translate to _10 equivalent.
+	     * (actually we should do this only if we have tried 
+	     * MODE_foo_6 and received ILLEGAL_REQUEST or
+	     * INVALID COMMAND OPERATION CODE)
+	     * alternative fix: behave like a honest CAM transport, 
+	     * do not muck with CDB contents, and change scsi_cd to 
+	     * always use MODE_SENSE_10 in cdgetmode(), or let scsi_cd
+	     * know that this specific unit is an ATAPI/MMC one, 
+	     * and in /that case/ use MODE_SENSE_10
+	     */
+
+#ifdef CAMDEBUG
+	    xpt_print_path(ccb_h->path);
+	    printf("Translating %s into _10 equivalent\n",
+		   (hcb->cmd[0] == MODE_SELECT_6) ?
+		   "MODE_SELECT_6" : "MODE_SENSE_6");
+#endif
+	    hcb->cmd[0] |= 0x40;
+	    hcb->cmd[6] = 0;
+	    hcb->cmd[7] = 0;
+	    hcb->cmd[8] = hcb->cmd[4];
+	    hcb->cmd[9] = hcb->cmd[5];
+	    hcb->cmd[4] = 0;
+	    hcb->cmd[5] = 0;
+	    break;
+
+	case READ_6:
+	    /* FALLTHROUGH */
+
+	case WRITE_6:
+#ifdef CAMDEBUG
+	    xpt_print_path(ccb_h->path);
+	    printf("Translating %s into _10 equivalent\n",
+		   (hcb->cmd[0] == READ_6) ? "READ_6" : "WRITE_6");
+#endif
+	    hcb->cmd[0] |= 0x20;
+	    hcb->cmd[9] = hcb->cmd[5];
+	    hcb->cmd[8] = hcb->cmd[4];
+	    hcb->cmd[7] = 0;
+	    hcb->cmd[6] = 0;
+	    hcb->cmd[5] = hcb->cmd[3];
+	    hcb->cmd[4] = hcb->cmd[2];
+	    hcb->cmd[3] = hcb->cmd[1] & 0x1f;
+	    hcb->cmd[2] = 0;
+	    hcb->cmd[1] = 0;
+	    break;
+	}
+
+	if ((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_IN && (len & 1)) {
+	    /* ATA always transfers an even number of bytes */
+	    if (!(buf = hcb->dxfer_alloc = malloc(++len, M_ATACAM,
+						  M_NOWAIT | M_ZERO)))
+		goto action_oom;
+	}
+	TAILQ_INSERT_TAIL(&softc->pending_hcbs, hcb, chain);
+	if (atapi_queue_cmd(dev, hcb->cmd, buf, len,
+			    (((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_IN) ?
+			    ATPR_F_READ : 0) | ATPR_F_QUIET,
+			    ccb_h->timeout, atapi_cb, (void *)hcb) == 0)
+	    return;
+	break;
+    }
+
+    default:
+	printf("atapi-cam: unsupported function code 0x%02x\n",
+	       ccb_h->func_code);
+	ccb_h->status = CAM_REQ_INVALID;
+	xpt_done(ccb);
+	return;
+    }
+
+action_oom:
+    if (hcb != NULL)
+	free_hcb(hcb);
+    xpt_print_path(ccb_h->path);
+    printf("Out of memory: freezing queue.");
+    softc->flags |= RESOURCE_SHORTAGE;
+    xpt_freeze_simq(sim, /*count*/ 1);
+    ccb_h->status = CAM_REQUEUE_REQ;
+    xpt_done(ccb);
+}
+
+static void 
+atapi_poll(struct cam_sim *sim)
+{
+    /* do nothing - we do not actually service any interrupts */
+    printf("atapi_poll called!\n");
+}
+
+int 
+atapi_cb(struct atapi_request *req)
+{
+    int s = splcam();
+    struct atapi_hcb *hcb = (struct atapi_hcb *) req->driver;
+    struct ccb_scsiio *csio = &hcb->ccb->csio;
+    int hcb_status = req->result;
+
+#ifdef CAMDEBUG
+    printf("atapi_cb: hcb@%p status = %02x: (sk = %02x%s%s%s)\n",
+	   hcb, hcb_status, hcb_status >> 4,
+	   (hcb_status & 4) ? " ABRT" : "",
+	   (hcb_status & 2) ? " EOM" : "",
+	   (hcb_status & 1) ? " ILI" : "");
+    printf("  %s: cmd %02x - sk=%02x asc=%02x ascq=%02x\n",
+	   req->device->name, req->ccb[0], req->sense.sense_key,
+	   req->sense.asc, req->sense.ascq);
+#endif
+    if (hcb_status != 0) {
+	hcb->ccb->csio.scsi_status = SCSI_STATUS_CHECK_COND;
+	if ((hcb->ccb->ccb_h.flags & CAM_DIS_AUTOSENSE) == 0) {
+	    hcb->ccb->ccb_h.status |= CAM_AUTOSNS_VALID;
+	    bcopy((void *)&req->sense, (void *)&csio->sense_data,
+		  sizeof(struct atapi_reqsense));
+	}
+	free_hcb_and_ccb_done(hcb, CAM_SCSI_STATUS_ERROR);
+    } 
+    else {
+	if (((hcb->ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN) &&
+	    hcb->dxfer_alloc != NULL)
+	    bcopy(hcb->dxfer_alloc, csio->data_ptr, csio->dxfer_len);
+	hcb->ccb->csio.scsi_status = SCSI_STATUS_OK;
+	free_hcb_and_ccb_done(hcb, CAM_REQ_CMP);
+    }
+    splx(s);
+    return 0;
+}
+
+static void
+free_hcb_and_ccb_done(struct atapi_hcb *hcb, u_int32_t status)
+{
+    struct atapi_xpt_softc *softc = hcb->softc;
+    union ccb *ccb = hcb->ccb;
+
+    if (hcb != NULL) {
+	/* we're about to free a hcb, so the shortage has ended */
+	if (softc->flags & RESOURCE_SHORTAGE) {
+	    softc->flags &= ~RESOURCE_SHORTAGE;
+	    status |= CAM_RELEASE_SIMQ;
+	}
+	free_hcb(hcb);
+    }
+    ccb->ccb_h.status = 
+	status | (ccb->ccb_h.status & ~(CAM_STATUS_MASK | CAM_SIM_QUEUED));
+    xpt_done(ccb);
+}
+
+static void 
+atapi_async(void *callback_arg, u_int32_t code,
+	    struct cam_path *path, void *arg)
+{
+    int s = splcam();
+
+    atapi_async1(callback_arg, code, path, arg);
+    splx(s);
+}
+
+static void 
+atapi_async1(void *callback_arg, u_int32_t code,
+	     struct cam_path* path, void *arg)
+{
+    struct atapi_xpt_softc *softc;
+    struct cam_sim *sim;
+    int targ;
+
+    sim = (struct cam_sim *) callback_arg;
+    softc = (struct atapi_xpt_softc *) cam_sim_softc(sim);
+    switch (code) {
+    case AC_LOST_DEVICE:
+	targ = xpt_path_target_id(path);
+	xpt_print_path(path);
+	if (targ == -1)
+		printf("Lost host adapter\n");
+	else
+		printf("Lost target %d???\n", targ);
+	break;
+
+    default:
+	break;
+    }
+}
+
+static void
+cam_rescan_callback(struct cam_periph *periph, union ccb *ccb)
+{
+#ifdef CAMDEBUG
+    xpt_print_path(ccb->ccb_h.path);
+	if (ccb->ccb_h.status != CAM_REQ_CMP)
+	    printf("Rescan failed, 0x%04x\n", ccb->ccb_h.status);
+	else
+	    printf("rescan succeeded\n");
+#endif
+	xpt_free_path(ccb->ccb_h.path);
+	free(ccb, M_ATACAM);
+}
+
+static void
+cam_rescan(struct cam_sim *sim)
+{
+    struct cam_path *path;
+    union ccb *ccb = malloc(sizeof(union ccb), M_ATACAM, M_WAITOK | M_ZERO);
+    
+#ifdef CAMDEBUG
+    xpt_print_path(cam_sim_path(sim));
+    printf ("rescanning ATAPI bus.\n");
+#endif
+    if (xpt_create_path(&path, xpt_periph, cam_sim_path(sim),
+			CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD) != CAM_REQ_CMP)
+	return;
+    
+    xpt_setup_ccb(&ccb->ccb_h, path, 5/*priority (low)*/);
+    ccb->ccb_h.func_code = XPT_SCAN_BUS;
+    ccb->ccb_h.cbfcnp = cam_rescan_callback;
+    ccb->crcn.flags = CAM_FLAG_NONE;
+    xpt_action(ccb);
+    /* scan is in progress now */
+}
+
+static struct atapi_hcb *
+allocate_hcb(struct atapi_xpt_softc *softc, int unit, int bus, union ccb *ccb)
+{
+    struct atapi_hcb *hcb = (struct atapi_hcb *)
+    malloc(sizeof(struct atapi_hcb), M_ATACAM, M_NOWAIT | M_ZERO);
+
+    if (hcb != NULL) {
+	hcb->softc = softc;
+	hcb->unit = unit;
+	hcb->bus = bus;
+	hcb->ccb = ccb;
+    }
+    return hcb;
+}
+
+static void 
+free_hcb(struct atapi_hcb *hcb)
+{
+    TAILQ_REMOVE(&hcb->softc->pending_hcbs, hcb, chain);
+    if (hcb->dxfer_alloc != NULL)
+	free(hcb->dxfer_alloc, M_ATACAM);
+    free(hcb, M_ATACAM);
+}
+
+static void
+free_softc(struct atapi_xpt_softc *scp)
+{
+    struct atapi_hcb *hcb;
+
+    if (scp != NULL) {
+	TAILQ_FOREACH(hcb, &scp->pending_hcbs, chain) {
+	    free_hcb_and_ccb_done(hcb, CAM_UNREC_HBA_ERROR);
+	}
+	if (scp->path != NULL) {
+	    setup_async_cb(scp, 0);
+	    xpt_free_path(scp->path);
+	}
+	if ((scp->flags & BUS_REGISTERED) != 0) {
+	    if (xpt_bus_deregister(cam_sim_path(scp->sim)) == CAM_REQ_CMP)
+		scp->flags &= ~BUS_REGISTERED;
+	}
+	if (scp->sim != NULL) {
+	    if ((scp->flags & BUS_REGISTERED) == 0)
+		cam_sim_free(scp->sim, /*free_devq*/TRUE);
+	    else
+		printf("Can't free %s SIM (still registered)\n",
+		       cam_sim_name(scp->sim));
+	}
+	LIST_REMOVE(scp, chain);
+	free(scp, M_ATACAM);
+    }
+}
+
+static struct ata_device *
+get_ata_device(struct atapi_xpt_softc *scp, int id)
+{
+    int role = ATA_ATAPI_MASTER;
+
+    switch (id) {
+    case 1:
+	role = ATA_ATAPI_SLAVE;
+	/* FALLTHROUGH */
+
+    case 0:
+	if (scp->ata_ch->devices & role)
+	    return &scp->ata_ch->device[id];
+	/* FALLTHROUGH */
+
+    default:
+	return NULL;
+    }
+}