xref: /dragonfly/sys/bus/cam/scsi/scsi_pt.c (revision 7d84b73d)
1 /*
2  * Implementation of SCSI Processor Target Peripheral driver for CAM.
3  *
4  * Copyright (c) 1998 Justin T. Gibbs.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification, immediately at the beginning of the file.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD: src/sys/cam/scsi/scsi_pt.c,v 1.17 2000/01/17 06:27:37 mjacob Exp $
29  */
30 
31 #include <sys/param.h>
32 #include <sys/queue.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/types.h>
36 #include <sys/buf.h>
37 #include <sys/devicestat.h>
38 #include <sys/malloc.h>
39 #include <sys/caps.h>
40 #include <sys/conf.h>
41 #include <sys/ptio.h>
42 #include <sys/buf2.h>
43 
44 #include "../cam.h"
45 #include "../cam_ccb.h"
46 #include "../cam_extend.h"
47 #include "../cam_periph.h"
48 #include "../cam_xpt_periph.h"
49 #include "../cam_debug.h"
50 
51 #include "scsi_all.h"
52 #include "scsi_message.h"
53 #include "scsi_pt.h"
54 
55 #include "opt_pt.h"
56 
57 typedef enum {
58 	PT_STATE_PROBE,
59 	PT_STATE_NORMAL
60 } pt_state;
61 
62 typedef enum {
63 	PT_FLAG_NONE		= 0x00,
64 	PT_FLAG_OPEN		= 0x01,
65 	PT_FLAG_DEVICE_INVALID	= 0x02,
66 	PT_FLAG_RETRY_UA	= 0x04
67 } pt_flags;
68 
69 typedef enum {
70 	PT_CCB_BUFFER_IO	= 0x01,
71 	PT_CCB_WAITING		= 0x02,
72 	PT_CCB_RETRY_UA		= 0x04,
73 	PT_CCB_BUFFER_IO_UA	= PT_CCB_BUFFER_IO|PT_CCB_RETRY_UA
74 } pt_ccb_state;
75 
76 /* Offsets into our private area for storing information */
77 #define ccb_state	ppriv_field0
78 #define ccb_bio		ppriv_ptr1
79 
80 struct pt_softc {
81 	struct	 bio_queue_head bio_queue;
82 	struct	 devstat device_stats;
83 	LIST_HEAD(, ccb_hdr) pending_ccbs;
84 	pt_state state;
85 	pt_flags flags;
86 	union	 ccb saved_ccb;
87 	int	 io_timeout;
88 	cdev_t	 dev;
89 };
90 
91 static	d_open_t	ptopen;
92 static	d_close_t	ptclose;
93 static	d_strategy_t	ptstrategy;
94 static	periph_init_t	ptinit;
95 static	void		ptasync(void *callback_arg, u_int32_t code,
96 				struct cam_path *path, void *arg);
97 static	periph_ctor_t	ptctor;
98 static	periph_oninv_t	ptoninvalidate;
99 static	periph_dtor_t	ptdtor;
100 static	periph_start_t	ptstart;
101 static	void		ptdone(struct cam_periph *periph,
102 			       union ccb *done_ccb);
103 static	d_ioctl_t	ptioctl;
104 static  int		pterror(union ccb *ccb, u_int32_t cam_flags,
105 				u_int32_t sense_flags);
106 
107 void	scsi_send_receive(struct ccb_scsiio *csio, u_int32_t retries,
108 			  void (*cbfcnp)(struct cam_periph *, union ccb *),
109 			  u_int tag_action, int readop, u_int byte2,
110 			  u_int32_t xfer_len, u_int8_t *data_ptr,
111 			  u_int8_t sense_len, u_int32_t timeout);
112 
113 static struct periph_driver ptdriver =
114 {
115 	ptinit, "pt",
116 	TAILQ_HEAD_INITIALIZER(ptdriver.units), /* generation */ 0
117 };
118 
119 PERIPHDRIVER_DECLARE(pt, ptdriver);
120 
121 static struct dev_ops pt_ops = {
122 	{ "pt", 0, 0 },
123 	.d_open =	ptopen,
124 	.d_close =	ptclose,
125 	.d_read =	physread,
126 	.d_write =	physwrite,
127 	.d_ioctl =	ptioctl,
128 	.d_strategy =	ptstrategy,
129 };
130 
131 static struct extend_array *ptperiphs;
132 
133 #ifndef SCSI_PT_DEFAULT_TIMEOUT
134 #define SCSI_PT_DEFAULT_TIMEOUT		60
135 #endif
136 
137 static int
138 ptopen(struct dev_open_args *ap)
139 {
140 	cdev_t dev = ap->a_head.a_dev;
141 	struct cam_periph *periph;
142 	struct pt_softc *softc;
143 	int unit;
144 	int error = 0;
145 
146 	/*
147 	 * Disallow CAM access if RESTRICTEDROOT
148 	 */
149 	if (caps_priv_check_self(SYSCAP_RESTRICTEDROOT))
150 		return (EPERM);
151 
152 	unit = minor(dev);
153 	periph = cam_extend_get(ptperiphs, unit);
154 	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
155 		return (ENXIO);
156 
157 	softc = (struct pt_softc *)periph->softc;
158 
159 	cam_periph_lock(periph);
160 	if (softc->flags & PT_FLAG_DEVICE_INVALID) {
161 		cam_periph_unlock(periph);
162 		cam_periph_release(periph);
163 		return(ENXIO);
164 	}
165 
166 	if ((softc->flags & PT_FLAG_OPEN) == 0)
167 		softc->flags |= PT_FLAG_OPEN;
168 	else {
169 		error = EBUSY;
170 		cam_periph_release(periph);
171 	}
172 
173 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
174 	    ("ptopen: dev=%s\n", devtoname(dev)));
175 
176 	cam_periph_unlock(periph);
177 	return (error);
178 }
179 
180 static int
181 ptclose(struct dev_close_args *ap)
182 {
183 	cdev_t dev = ap->a_head.a_dev;
184 	struct	cam_periph *periph;
185 	struct	pt_softc *softc;
186 	int	unit;
187 
188 	unit = minor(dev);
189 	periph = cam_extend_get(ptperiphs, unit);
190 	if (periph == NULL)
191 		return (ENXIO);
192 
193 	softc = (struct pt_softc *)periph->softc;
194 
195 	cam_periph_lock(periph);
196 
197 	softc->flags &= ~PT_FLAG_OPEN;
198 	cam_periph_unlock(periph);
199 	cam_periph_release(periph);
200 	return (0);
201 }
202 
203 /*
204  * Actually translate the requested transfer into one the physical driver
205  * can understand.  The transfer is described by a buf and will include
206  * only one physical transfer.
207  */
208 static int
209 ptstrategy(struct dev_strategy_args *ap)
210 {
211 	cdev_t dev = ap->a_head.a_dev;
212 	struct bio *bio = ap->a_bio;
213 	struct buf *bp = bio->bio_buf;
214 	struct cam_periph *periph;
215 	struct pt_softc *softc;
216 	u_int  unit;
217 
218 	unit = minor(dev);
219 	periph = cam_extend_get(ptperiphs, unit);
220 	if (periph == NULL) {
221 		bp->b_error = ENXIO;
222 		goto bad;
223 	}
224 	cam_periph_lock(periph);
225 	softc = (struct pt_softc *)periph->softc;
226 
227 	/*
228 	 * If the device has been made invalid, error out
229 	 */
230 	if ((softc->flags & PT_FLAG_DEVICE_INVALID)) {
231 		cam_periph_unlock(periph);
232 		bp->b_error = ENXIO;
233 		goto bad;
234 	}
235 
236 	/*
237 	 * Place it in the queue of disk activities for this disk
238 	 */
239 	bioq_insert_tail(&softc->bio_queue, bio);
240 
241 	/*
242 	 * Schedule ourselves for performing the work.
243 	 */
244 	xpt_schedule(periph, /* XXX priority */1);
245 	cam_periph_unlock(periph);
246 
247 	return(0);
248 bad:
249 	bp->b_flags |= B_ERROR;
250 
251 	/*
252 	 * Correctly set the buf to indicate a completed xfer
253 	 */
254 	bp->b_resid = bp->b_bcount;
255 	biodone(bio);
256 	return(0);
257 }
258 
259 static void
260 ptinit(void)
261 {
262 	cam_status status;
263 
264 	/*
265 	 * Create our extend array for storing the devices we attach to.
266 	 */
267 	ptperiphs = cam_extend_new();
268 	if (ptperiphs == NULL) {
269 		kprintf("pt: Failed to alloc extend array!\n");
270 		return;
271 	}
272 
273 	/*
274 	 * Install a global async callback.  This callback will
275 	 * receive async callbacks like "new device found".
276 	 */
277 	status = xpt_register_async(AC_FOUND_DEVICE, ptasync, NULL, NULL);
278 
279 	if (status != CAM_REQ_CMP) {
280 		kprintf("pt: Failed to attach master async callback "
281 		       "due to status 0x%x!\n", status);
282 	}
283 }
284 
285 static cam_status
286 ptctor(struct cam_periph *periph, void *arg)
287 {
288 	struct pt_softc *softc;
289 	struct ccb_getdev *cgd;
290 
291 	cgd = (struct ccb_getdev *)arg;
292 	if (periph == NULL) {
293 		kprintf("ptregister: periph was NULL!!\n");
294 		return(CAM_REQ_CMP_ERR);
295 	}
296 
297 	if (cgd == NULL) {
298 		kprintf("ptregister: no getdev CCB, can't register device\n");
299 		return(CAM_REQ_CMP_ERR);
300 	}
301 
302 	softc = kmalloc(sizeof(*softc), M_DEVBUF, M_INTWAIT | M_ZERO);
303 	LIST_INIT(&softc->pending_ccbs);
304 	softc->state = PT_STATE_NORMAL;
305 	bioq_init(&softc->bio_queue);
306 
307 	softc->io_timeout = SCSI_PT_DEFAULT_TIMEOUT * 1000;
308 
309 	periph->softc = softc;
310 
311 	cam_periph_unlock(periph);
312 	cam_extend_set(ptperiphs, periph->unit_number, periph);
313 
314 	devstat_add_entry(&softc->device_stats, "pt",
315 			  periph->unit_number, 0,
316 			  DEVSTAT_NO_BLOCKSIZE,
317 			  SID_TYPE(&cgd->inq_data) | DEVSTAT_TYPE_IF_SCSI,
318 			  DEVSTAT_PRIORITY_OTHER);
319 
320 	make_dev(&pt_ops, periph->unit_number, UID_ROOT,
321 		  GID_OPERATOR, 0600, "%s%d", periph->periph_name,
322 		  periph->unit_number);
323 	cam_periph_lock(periph);
324 	/*
325 	 * Add async callbacks for bus reset and
326 	 * bus device reset calls.  I don't bother
327 	 * checking if this fails as, in most cases,
328 	 * the system will function just fine without
329 	 * them and the only alternative would be to
330 	 * not attach the device on failure.
331 	 */
332 	xpt_register_async(AC_SENT_BDR | AC_BUS_RESET | AC_LOST_DEVICE,
333 			   ptasync, periph, periph->path);
334 
335 	/* Tell the user we've attached to the device */
336 	xpt_announce_periph(periph, NULL);
337 
338 	return(CAM_REQ_CMP);
339 }
340 
341 static void
342 ptoninvalidate(struct cam_periph *periph)
343 {
344 	struct pt_softc *softc;
345 	struct bio *q_bio;
346 	struct buf *q_bp;
347 
348 	softc = (struct pt_softc *)periph->softc;
349 
350 	/*
351 	 * De-register any async callbacks.
352 	 */
353 	xpt_register_async(0, ptasync, periph, periph->path);
354 
355 	softc->flags |= PT_FLAG_DEVICE_INVALID;
356 
357 	/*
358 	 * Return all queued I/O with ENXIO.
359 	 * XXX Handle any transactions queued to the card
360 	 *     with XPT_ABORT_CCB.
361 	 */
362 	while ((q_bio = bioq_takefirst(&softc->bio_queue)) != NULL) {
363 		q_bp = q_bio->bio_buf;
364 		q_bp->b_resid = q_bp->b_bcount;
365 		q_bp->b_error = ENXIO;
366 		q_bp->b_flags |= B_ERROR;
367 		biodone(q_bio);
368 	}
369 
370 	xpt_print(periph->path, "lost device\n");
371 }
372 
373 static void
374 ptdtor(struct cam_periph *periph)
375 {
376 	struct pt_softc *softc;
377 
378 	softc = (struct pt_softc *)periph->softc;
379 
380 	devstat_remove_entry(&softc->device_stats);
381 
382 	cam_extend_release(ptperiphs, periph->unit_number);
383 	xpt_print(periph->path, "removing device entry\n");
384 	dev_ops_remove_minor(&pt_ops, periph->unit_number);
385 	kfree(softc, M_DEVBUF);
386 }
387 
388 static void
389 ptasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
390 {
391 	struct cam_periph *periph;
392 
393 	periph = (struct cam_periph *)callback_arg;
394 	switch (code) {
395 	case AC_FOUND_DEVICE:
396 	{
397 		struct ccb_getdev *cgd;
398 		cam_status status;
399 
400 		cgd = (struct ccb_getdev *)arg;
401 		if (cgd == NULL)
402 			break;
403 
404 		if (SID_TYPE(&cgd->inq_data) != T_PROCESSOR)
405 			break;
406 
407 		/*
408 		 * Allocate a peripheral instance for
409 		 * this device and start the probe
410 		 * process.
411 		 */
412 		status = cam_periph_alloc(ptctor, ptoninvalidate, ptdtor,
413 					  ptstart, "pt", CAM_PERIPH_BIO,
414 					  cgd->ccb_h.path, ptasync,
415 					  AC_FOUND_DEVICE, cgd);
416 
417 		if (status != CAM_REQ_CMP
418 		 && status != CAM_REQ_INPROG)
419 			kprintf("ptasync: Unable to attach to new device "
420 				"due to status 0x%x\n", status);
421 		break;
422 	}
423 	case AC_SENT_BDR:
424 	case AC_BUS_RESET:
425 	{
426 		struct pt_softc *softc;
427 		struct ccb_hdr *ccbh;
428 
429 		softc = (struct pt_softc *)periph->softc;
430 		/*
431 		 * Don't fail on the expected unit attention
432 		 * that will occur.
433 		 */
434 		softc->flags |= PT_FLAG_RETRY_UA;
435 		LIST_FOREACH(ccbh, &softc->pending_ccbs, periph_links.le)
436 			ccbh->ccb_state |= PT_CCB_RETRY_UA;
437 		/* FALLTHROUGH */
438 	}
439 	default:
440 		cam_periph_async(periph, code, path, arg);
441 		break;
442 	}
443 }
444 
445 static void
446 ptstart(struct cam_periph *periph, union ccb *start_ccb)
447 {
448 	struct pt_softc *softc;
449 	struct buf *bp;
450 	struct bio *bio;
451 
452 	softc = (struct pt_softc *)periph->softc;
453 
454 	/*
455 	 * See if there is a buf with work for us to do..
456 	 */
457 	bio = bioq_first(&softc->bio_queue);
458 	if (periph->immediate_priority <= periph->pinfo.priority) {
459 		CAM_DEBUG_PRINT(CAM_DEBUG_SUBTRACE,
460 				("queuing for immediate ccb\n"));
461 		start_ccb->ccb_h.ccb_state = PT_CCB_WAITING;
462 		SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
463 				  periph_links.sle);
464 		periph->immediate_priority = CAM_PRIORITY_NONE;
465 		wakeup(&periph->ccb_list);
466 	} else if (bio == NULL) {
467 		xpt_release_ccb(start_ccb);
468 	} else {
469 		bioq_remove(&softc->bio_queue, bio);
470 		bp = bio->bio_buf;
471 
472 		devstat_start_transaction(&softc->device_stats);
473 
474 		scsi_send_receive(&start_ccb->csio,
475 				  /*retries*/4,
476 				  ptdone,
477 				  MSG_SIMPLE_Q_TAG,
478 				  (bp->b_cmd == BUF_CMD_READ),
479 				  /*byte2*/0,
480 				  bp->b_bcount,
481 				  bp->b_data,
482 				  /*sense_len*/SSD_FULL_SIZE,
483 				  /*timeout*/softc->io_timeout);
484 
485 		start_ccb->ccb_h.ccb_state = PT_CCB_BUFFER_IO_UA;
486 
487 		/*
488 		 * Block out any asyncronous callbacks
489 		 * while we touch the pending ccb list.
490 		 */
491 		LIST_INSERT_HEAD(&softc->pending_ccbs, &start_ccb->ccb_h,
492 				 periph_links.le);
493 
494 		start_ccb->ccb_h.ccb_bio = bio;
495 		bio = bioq_first(&softc->bio_queue);
496 
497 		xpt_action(start_ccb);
498 
499 		if (bio != NULL) {
500 			/* Have more work to do, so ensure we stay scheduled */
501 			xpt_schedule(periph, /* XXX priority */1);
502 		}
503 	}
504 }
505 
506 static void
507 ptdone(struct cam_periph *periph, union ccb *done_ccb)
508 {
509 	struct pt_softc *softc;
510 	struct ccb_scsiio *csio;
511 
512 	softc = (struct pt_softc *)periph->softc;
513 	csio = &done_ccb->csio;
514 	switch (csio->ccb_h.ccb_state) {
515 	case PT_CCB_BUFFER_IO:
516 	case PT_CCB_BUFFER_IO_UA:
517 	{
518 		struct buf *bp;
519 		struct bio *bio;
520 
521 		bio = (struct bio *)done_ccb->ccb_h.ccb_bio;
522 		bp = bio->bio_buf;
523 
524 		if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
525 			int error;
526 			int sf;
527 
528 			if ((csio->ccb_h.ccb_state & PT_CCB_RETRY_UA) != 0)
529 				sf = SF_RETRY_UA;
530 			else
531 				sf = 0;
532 
533 			error = pterror(done_ccb, CAM_RETRY_SELTO, sf);
534 			if (error == ERESTART) {
535 				/*
536 				 * A retry was scheuled, so
537 				 * just return.
538 				 */
539 				return;
540 			}
541 			if (error != 0) {
542 				struct buf *q_bp;
543 				struct bio *q_bio;
544 
545 				if (error == ENXIO) {
546 					/*
547 					 * Catastrophic error.  Mark our device
548 					 * as invalid.
549 					 */
550 					xpt_print(periph->path,
551 					    "Invalidating device\n");
552 					softc->flags |= PT_FLAG_DEVICE_INVALID;
553 				}
554 
555 				/*
556 				 * return all queued I/O with EIO, so that
557 				 * the client can retry these I/Os in the
558 				 * proper order should it attempt to recover.
559 				 */
560 				while ((q_bio = bioq_takefirst(&softc->bio_queue)) != NULL) {
561 					q_bp = q_bio->bio_buf;
562 					q_bp->b_resid = q_bp->b_bcount;
563 					q_bp->b_error = EIO;
564 					q_bp->b_flags |= B_ERROR;
565 					biodone(q_bio);
566 				}
567 				bp->b_error = error;
568 				bp->b_resid = bp->b_bcount;
569 				bp->b_flags |= B_ERROR;
570 			} else {
571 				bp->b_resid = csio->resid;
572 				bp->b_error = 0;
573 				if (bp->b_resid != 0) {
574 					/* Short transfer ??? */
575 					bp->b_flags |= B_ERROR;
576 				}
577 			}
578 			if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
579 				cam_release_devq(done_ccb->ccb_h.path,
580 						 /*relsim_flags*/0,
581 						 /*reduction*/0,
582 						 /*timeout*/0,
583 						 /*getcount_only*/0);
584 		} else {
585 			bp->b_resid = csio->resid;
586 			if (bp->b_resid != 0)
587 				bp->b_flags |= B_ERROR;
588 		}
589 
590 		/*
591 		 * Block out any asyncronous callbacks
592 		 * while we touch the pending ccb list.
593 		 */
594 		LIST_REMOVE(&done_ccb->ccb_h, periph_links.le);
595 
596 		devstat_end_transaction_buf(&softc->device_stats, bp);
597 		biodone(bio);
598 		break;
599 	}
600 	case PT_CCB_WAITING:
601 		/* Caller will release the CCB */
602 		wakeup(&done_ccb->ccb_h.cbfcnp);
603 		return;
604 	}
605 	xpt_release_ccb(done_ccb);
606 }
607 
608 static int
609 pterror(union ccb *ccb, u_int32_t cam_flags, u_int32_t sense_flags)
610 {
611 	struct pt_softc	  *softc;
612 	struct cam_periph *periph;
613 
614 	periph = xpt_path_periph(ccb->ccb_h.path);
615 	softc = (struct pt_softc *)periph->softc;
616 
617 	return(cam_periph_error(ccb, cam_flags, sense_flags,
618 				&softc->saved_ccb));
619 }
620 
621 static int
622 ptioctl(struct dev_ioctl_args *ap)
623 {
624 	cdev_t dev = ap->a_head.a_dev;
625 	caddr_t addr = ap->a_data;
626 	struct cam_periph *periph;
627 	struct pt_softc *softc;
628 	int unit;
629 	int error = 0;
630 
631 	unit = minor(dev);
632 	periph = cam_extend_get(ptperiphs, unit);
633 
634 	if (periph == NULL)
635 		return(ENXIO);
636 
637 	softc = (struct pt_softc *)periph->softc;
638 
639 	cam_periph_lock(periph);
640 
641 	switch(ap->a_cmd) {
642 	case PTIOCGETTIMEOUT:
643 		if (softc->io_timeout >= 1000)
644 			*(int *)addr = softc->io_timeout / 1000;
645 		else
646 			*(int *)addr = 0;
647 		break;
648 	case PTIOCSETTIMEOUT:
649 		if (*(int *)addr < 1) {
650 			error = EINVAL;
651 			break;
652 		}
653 
654 		softc->io_timeout = *(int *)addr * 1000;
655 
656 		break;
657 	default:
658 		error = cam_periph_ioctl(periph, ap->a_cmd, addr, pterror);
659 		break;
660 	}
661 
662 	cam_periph_unlock(periph);
663 
664 	return(error);
665 }
666 
667 void
668 scsi_send_receive(struct ccb_scsiio *csio, u_int32_t retries,
669 		  void (*cbfcnp)(struct cam_periph *, union ccb *),
670 		  u_int tag_action, int readop, u_int byte2,
671 		  u_int32_t xfer_len, u_int8_t *data_ptr, u_int8_t sense_len,
672 		  u_int32_t timeout)
673 {
674 	struct scsi_send_receive *scsi_cmd;
675 
676 	scsi_cmd = (struct scsi_send_receive *)&csio->cdb_io.cdb_bytes;
677 	scsi_cmd->opcode = readop ? RECEIVE : SEND;
678 	scsi_cmd->byte2 = byte2;
679 	scsi_ulto3b(xfer_len, scsi_cmd->xfer_len);
680 	scsi_cmd->control = 0;
681 
682 	cam_fill_csio(csio,
683 		      retries,
684 		      cbfcnp,
685 		      /*flags*/readop ? CAM_DIR_IN : CAM_DIR_OUT,
686 		      tag_action,
687 		      data_ptr,
688 		      xfer_len,
689 		      sense_len,
690 		      sizeof(*scsi_cmd),
691 		      timeout);
692 }
693