xref: /freebsd/sys/cam/scsi/scsi_sa.c (revision 64db83a8ab2d1f72a9b2174b39d2ef42b5b0580c)
1 /*
2  * $FreeBSD$
3  *
4  * Implementation of SCSI Sequential Access Peripheral driver for CAM.
5  *
6  * Copyright (c) 1999, 2000 Matthew Jacob
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions, and the following disclaimer,
14  *    without modification, immediately at the beginning of the file.
15  * 2. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
22  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 #include <sys/param.h>
33 #include <sys/queue.h>
34 #ifdef _KERNEL
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #endif
38 #include <sys/types.h>
39 #include <sys/bio.h>
40 #include <sys/malloc.h>
41 #include <sys/mtio.h>
42 #include <sys/conf.h>
43 #include <sys/devicestat.h>
44 #include <machine/limits.h>
45 
46 #ifndef _KERNEL
47 #include <stdio.h>
48 #include <string.h>
49 #endif
50 
51 #include <cam/cam.h>
52 #include <cam/cam_ccb.h>
53 #include <cam/cam_extend.h>
54 #include <cam/cam_periph.h>
55 #include <cam/cam_xpt_periph.h>
56 #include <cam/cam_debug.h>
57 
58 #include <cam/scsi/scsi_all.h>
59 #include <cam/scsi/scsi_message.h>
60 #include <cam/scsi/scsi_sa.h>
61 
62 #ifdef _KERNEL
63 
64 #include <opt_sa.h>
65 
66 #ifndef SA_SPACE_TIMEOUT
67 #define SA_SPACE_TIMEOUT	1 * 60
68 #endif
69 #ifndef SA_REWIND_TIMEOUT
70 #define SA_REWIND_TIMEOUT	2 * 60
71 #endif
72 #ifndef SA_ERASE_TIMEOUT
73 #define SA_ERASE_TIMEOUT	4 * 60
74 #endif
75 
76 #define	REWIND_TIMEOUT		(SA_REWIND_TIMEOUT * 60 * 1000)
77 #define	ERASE_TIMEOUT		(SA_ERASE_TIMEOUT * 60 * 1000)
78 #define	SPACE_TIMEOUT		(SA_SPACE_TIMEOUT * 60 * 1000)
79 
80 /*
81  * Additional options that can be set for config: SA_1FM_AT_EOT
82  */
83 
84 #ifndef	UNUSED_PARAMETER
85 #define	UNUSED_PARAMETER(x)	x = x
86 #endif
87 
88 #define	QFRLS(ccb)	\
89 	if (((ccb)->ccb_h.status & CAM_DEV_QFRZN) != 0)	\
90 		cam_release_devq((ccb)->ccb_h.path, 0, 0, 0, FALSE)
91 
92 /*
93  * Driver states
94  */
95 
96 
97 typedef enum {
98 	SA_STATE_NORMAL, SA_STATE_ABNORMAL
99 } sa_state;
100 
101 typedef enum {
102 	SA_CCB_BUFFER_IO,
103 	SA_CCB_WAITING
104 } sa_ccb_types;
105 
106 #define ccb_type ppriv_field0
107 #define ccb_bp	 ppriv_ptr1
108 
109 typedef enum {
110 	SA_FLAG_OPEN		= 0x0001,
111 	SA_FLAG_FIXED		= 0x0002,
112 	SA_FLAG_TAPE_LOCKED	= 0x0004,
113 	SA_FLAG_TAPE_MOUNTED	= 0x0008,
114 	SA_FLAG_TAPE_WP		= 0x0010,
115 	SA_FLAG_TAPE_WRITTEN	= 0x0020,
116 	SA_FLAG_EOM_PENDING	= 0x0040,
117 	SA_FLAG_EIO_PENDING	= 0x0080,
118 	SA_FLAG_EOF_PENDING	= 0x0100,
119 	SA_FLAG_ERR_PENDING	= (SA_FLAG_EOM_PENDING|SA_FLAG_EIO_PENDING|
120 				   SA_FLAG_EOF_PENDING),
121 	SA_FLAG_INVALID		= 0x0200,
122 	SA_FLAG_COMP_ENABLED	= 0x0400,
123 	SA_FLAG_COMP_SUPP	= 0x0800,
124 	SA_FLAG_COMP_UNSUPP	= 0x1000,
125 	SA_FLAG_TAPE_FROZEN	= 0x2000
126 } sa_flags;
127 
128 typedef enum {
129 	SA_MODE_REWIND		= 0x00,
130 	SA_MODE_NOREWIND	= 0x01,
131 	SA_MODE_OFFLINE		= 0x02
132 } sa_mode;
133 
134 typedef enum {
135 	SA_PARAM_NONE		= 0x00,
136 	SA_PARAM_BLOCKSIZE	= 0x01,
137 	SA_PARAM_DENSITY	= 0x02,
138 	SA_PARAM_COMPRESSION	= 0x04,
139 	SA_PARAM_BUFF_MODE	= 0x08,
140 	SA_PARAM_NUMBLOCKS	= 0x10,
141 	SA_PARAM_WP		= 0x20,
142 	SA_PARAM_SPEED		= 0x40,
143 	SA_PARAM_ALL		= 0x7f
144 } sa_params;
145 
146 typedef enum {
147 	SA_QUIRK_NONE		= 0x00,
148 	SA_QUIRK_NOCOMP		= 0x01,	/* Can't deal with compression at all */
149 	SA_QUIRK_FIXED		= 0x02,	/* Force fixed mode */
150 	SA_QUIRK_VARIABLE	= 0x04,	/* Force variable mode */
151 	SA_QUIRK_2FM		= 0x08,	/* Needs Two File Marks at EOD */
152 	SA_QUIRK_1FM		= 0x10,	/* No more than 1 File Mark at EOD */
153 	SA_QUIRK_NODREAD	= 0x20,	/* Don't try and dummy read density */
154 	SA_QUIRK_NO_MODESEL	= 0x40	/* Don't do mode select at all */
155 } sa_quirks;
156 
157 /* units are bits 4-7, 16-21 (1024 units) */
158 #define SAUNIT(DEV) \
159 	(((minor(DEV) & 0xF0) >> 4) |  ((minor(DEV) & 0x3f0000) >> 16))
160 
161 #define SAMODE(z) ((minor(z) & 0x3))
162 #define SADENSITY(z) (((minor(z) >> 2) & 0x3))
163 #define	SA_IS_CTRL(z) (minor(z) & (1 << 29))
164 
165 #define SA_NOT_CTLDEV	0
166 #define SA_CTLDEV	1
167 
168 #define SA_ATYPE_R	0
169 #define SA_ATYPE_NR	1
170 #define SA_ATYPE_ER	2
171 
172 #define SAMINOR(ctl, unit, mode, access) \
173 	((ctl << 29) | ((unit & 0x3f0) << 16) | ((unit & 0xf) << 4) | \
174 	(mode << 0x2) | (access & 0x3))
175 
176 #define SA_NUM_MODES	4
177 struct sa_devs {
178 	dev_t	ctl_dev;
179 	struct sa_mode_devs {
180 		dev_t	r_dev;
181 		dev_t	nr_dev;
182 		dev_t	er_dev;
183 	} mode_devs[SA_NUM_MODES];
184 	dev_t	r_dev;
185 	dev_t	nr_dev;
186 	dev_t	er_dev;
187 };
188 
189 struct sa_softc {
190 	sa_state	state;
191 	sa_flags	flags;
192 	sa_quirks	quirks;
193 	struct		bio_queue_head bio_queue;
194 	int		queue_count;
195 	struct		devstat device_stats;
196 	struct sa_devs	devs;
197 	int		blk_gran;
198 	int		blk_mask;
199 	int		blk_shift;
200 	u_int32_t	max_blk;
201 	u_int32_t	min_blk;
202 	u_int32_t	comp_algorithm;
203 	u_int32_t	saved_comp_algorithm;
204 	u_int32_t	media_blksize;
205 	u_int32_t	last_media_blksize;
206 	u_int32_t	media_numblks;
207 	u_int8_t	media_density;
208 	u_int8_t	speed;
209 	u_int8_t	scsi_rev;
210 	u_int8_t	dsreg;		/* mtio mt_dsreg, redux */
211 	int		buffer_mode;
212 	int		filemarks;
213 	union		ccb saved_ccb;
214 
215 	/*
216 	 * Relative to BOT Location.
217 	 */
218 	daddr_t		fileno;
219 	daddr_t		blkno;
220 
221 	/*
222 	 * Latched Error Info
223 	 */
224 	struct {
225 		struct scsi_sense_data _last_io_sense;
226 		u_int32_t _last_io_resid;
227 		u_int8_t _last_io_cdb[CAM_MAX_CDBLEN];
228 		struct scsi_sense_data _last_ctl_sense;
229 		u_int32_t _last_ctl_resid;
230 		u_int8_t _last_ctl_cdb[CAM_MAX_CDBLEN];
231 #define	last_io_sense	errinfo._last_io_sense
232 #define	last_io_resid	errinfo._last_io_resid
233 #define	last_io_cdb	errinfo._last_io_cdb
234 #define	last_ctl_sense	errinfo._last_ctl_sense
235 #define	last_ctl_resid	errinfo._last_ctl_resid
236 #define	last_ctl_cdb	errinfo._last_ctl_cdb
237 	} errinfo;
238 	/*
239 	 * Misc other flags/state
240 	 */
241 	u_int32_t
242 				: 31,
243 		ctrl_mode	: 1;	/* control device open */
244 };
245 
246 struct sa_quirk_entry {
247 	struct scsi_inquiry_pattern inq_pat;	/* matching pattern */
248 	sa_quirks quirks;	/* specific quirk type */
249 	u_int32_t prefblk;	/* preferred blocksize when in fixed mode */
250 };
251 
252 static struct sa_quirk_entry sa_quirk_table[] =
253 {
254 	{
255 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "OnStream",
256 		  "ADR*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_NODREAD |
257 		   SA_QUIRK_1FM|SA_QUIRK_NO_MODESEL, 32768
258 	},
259 	{
260 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
261 		  "Python 25601*", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_NODREAD, 0
262 	},
263 	{
264 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
265 		  "Python*", "*"}, SA_QUIRK_NODREAD, 0
266 	},
267 	{
268 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
269 		  "VIPER 150*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
270 	},
271 	{
272 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
273 		  "VIPER 2525*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 1024
274 	},
275 	{
276 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
277 		  "T20*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
278 	},
279 	{
280 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
281 		  "T4000*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
282 	},
283 	{
284 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
285 		  "HP-88780*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
286 	},
287 	{
288 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "KENNEDY",
289 		  "*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
290 	},
291 	{
292 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "M4 DATA",
293 		  "123107 SCSI*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
294 	},
295 	{	/* jreynold@primenet.com */
296 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "Seagate",
297 		"STT8000N*", "*"}, SA_QUIRK_1FM, 0
298 	},
299 	{	/* mike@sentex.net */
300 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "Seagate",
301 		"STT20000*", "*"}, SA_QUIRK_1FM, 0
302 	},
303 	{
304 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
305 		  " TDC 3600", "U07:"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
306 	},
307 	{
308 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
309 		  " TDC 3800", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
310 	},
311 	{
312 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
313 		  " TDC 4100", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
314 	},
315 	{
316 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
317 		  " TDC 4200", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
318 	},
319 	{
320 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
321 		  " SLR*", "*"}, SA_QUIRK_1FM, 0
322 	},
323 	{
324 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "WANGTEK",
325 		  "5525ES*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
326 	},
327 	{
328 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "WANGTEK",
329 		  "51000*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 1024
330 	}
331 };
332 
333 static	d_open_t	saopen;
334 static	d_close_t	saclose;
335 static	d_strategy_t	sastrategy;
336 static	d_ioctl_t	saioctl;
337 static	periph_init_t	sainit;
338 static	periph_ctor_t	saregister;
339 static	periph_oninv_t	saoninvalidate;
340 static	periph_dtor_t	sacleanup;
341 static	periph_start_t	sastart;
342 static	void		saasync(void *callback_arg, u_int32_t code,
343 				struct cam_path *path, void *arg);
344 static	void		sadone(struct cam_periph *periph,
345 			       union ccb *start_ccb);
346 static  int		saerror(union ccb *ccb, u_int32_t cam_flags,
347 				u_int32_t sense_flags);
348 static int		sacheckeod(struct cam_periph *periph);
349 static int		sagetparams(struct cam_periph *periph,
350 				    sa_params params_to_get,
351 				    u_int32_t *blocksize, u_int8_t *density,
352 				    u_int32_t *numblocks, int *buff_mode,
353 				    u_int8_t *write_protect, u_int8_t *speed,
354 				    int *comp_supported, int *comp_enabled,
355 				    u_int32_t *comp_algorithm,
356 				    sa_comp_t *comp_page);
357 static int		sasetparams(struct cam_periph *periph,
358 				    sa_params params_to_set,
359 				    u_int32_t blocksize, u_int8_t density,
360 				    u_int32_t comp_algorithm,
361 				    u_int32_t sense_flags);
362 static void		saprevent(struct cam_periph *periph, int action);
363 static int		sarewind(struct cam_periph *periph);
364 static int		saspace(struct cam_periph *periph, int count,
365 				scsi_space_code code);
366 static int		samount(struct cam_periph *, int, dev_t);
367 static int		saretension(struct cam_periph *periph);
368 static int		sareservereleaseunit(struct cam_periph *periph,
369 					     int reserve);
370 static int		saloadunload(struct cam_periph *periph, int load);
371 static int		saerase(struct cam_periph *periph, int longerase);
372 static int		sawritefilemarks(struct cam_periph *periph,
373 					 int nmarks, int setmarks);
374 static int		sardpos(struct cam_periph *periph, int, u_int32_t *);
375 static int		sasetpos(struct cam_periph *periph, int, u_int32_t *);
376 
377 
378 static struct periph_driver sadriver =
379 {
380 	sainit, "sa",
381 	TAILQ_HEAD_INITIALIZER(sadriver.units), /* generation */ 0
382 };
383 
384 DATA_SET(periphdriver_set, sadriver);
385 
386 /* For 2.2-stable support */
387 #ifndef D_TAPE
388 #define D_TAPE 0
389 #endif
390 
391 #define SA_CDEV_MAJOR 14
392 
393 static struct cdevsw sa_cdevsw = {
394 	/* open */	saopen,
395 	/* close */	saclose,
396 	/* read */	physread,
397 	/* write */	physwrite,
398 	/* ioctl */	saioctl,
399 	/* poll */	nopoll,
400 	/* mmap */	nommap,
401 	/* strategy */	sastrategy,
402 	/* name */	"sa",
403 	/* maj */	SA_CDEV_MAJOR,
404 	/* dump */	nodump,
405 	/* psize */	nopsize,
406 	/* flags */	D_TAPE,
407 	/* bmaj */	-1
408 };
409 
410 static struct extend_array *saperiphs;
411 
412 static int
413 saopen(dev_t dev, int flags, int fmt, struct proc *p)
414 {
415 	struct cam_periph *periph;
416 	struct sa_softc *softc;
417 	int unit;
418 	int mode;
419 	int density;
420 	int error;
421 	int s;
422 
423 	unit = SAUNIT(dev);
424 	mode = SAMODE(dev);
425 	density = SADENSITY(dev);
426 
427 	s = splsoftcam();
428 	periph = cam_extend_get(saperiphs, unit);
429 	if (periph == NULL) {
430 		(void) splx(s);
431 		return (ENXIO);
432 	}
433 	softc = (struct sa_softc *)periph->softc;
434 	if ((error = cam_periph_lock(periph, PRIBIO|PCATCH)) != 0) {
435 		splx(s);
436 		return (error);
437 	}
438 	splx(s);
439 
440 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE|CAM_DEBUG_INFO,
441 	    ("saopen(%d): dev=0x%x softc=0x%x\n", unit, unit, softc->flags));
442 
443 	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
444 		cam_periph_unlock(periph);
445 		return (ENXIO);
446 	}
447 	if (SA_IS_CTRL(dev)) {
448 		softc->ctrl_mode = 1;
449 		cam_periph_unlock(periph);
450 		return (0);
451 	}
452 
453 
454 	if (softc->flags & SA_FLAG_OPEN) {
455 		error = EBUSY;
456 	} else if (softc->flags & SA_FLAG_INVALID) {
457 		error = ENXIO;
458 	} else {
459 		/*
460 		 * The function samount ensures media is loaded and ready.
461 		 * It also does a device RESERVE if the tape isn't yet mounted.
462 		 */
463 		error = samount(periph, flags, dev);
464 	}
465 
466 	if (error) {
467 		cam_periph_release(periph);
468 	} else {
469 		saprevent(periph, PR_PREVENT);
470 		softc->flags |= SA_FLAG_OPEN;
471 	}
472 	cam_periph_unlock(periph);
473 	return (error);
474 }
475 
476 static int
477 saclose(dev_t dev, int flag, int fmt, struct proc *p)
478 {
479 	struct	cam_periph *periph;
480 	struct	sa_softc *softc;
481 	int	unit, mode, error, writing, tmp;
482 	int	closedbits = SA_FLAG_OPEN;
483 
484 	unit = SAUNIT(dev);
485 	mode = SAMODE(dev);
486 	periph = cam_extend_get(saperiphs, unit);
487 	if (periph == NULL)
488 		return (ENXIO);
489 
490 	softc = (struct sa_softc *)periph->softc;
491 
492 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE|CAM_DEBUG_INFO,
493 	    ("saclose(%d): dev=0x%x softc=0x%x\n", unit, unit, softc->flags));
494 
495 
496 	if ((error = cam_periph_lock(periph, PRIBIO)) != 0) {
497 		return (error);
498 	}
499 
500 	if (SA_IS_CTRL(dev)) {
501 		softc->ctrl_mode = 0;
502 		cam_periph_release(periph);
503 		cam_periph_unlock(periph);
504 		return (0);
505 	}
506 
507 	/*
508 	 * Were we writing the tape?
509 	 */
510 	writing = (softc->flags & SA_FLAG_TAPE_WRITTEN) != 0;
511 
512 	/*
513 	 * See whether or not we need to write filemarks. If this
514 	 * fails, we probably have to assume we've lost tape
515 	 * position.
516 	 */
517 	error = sacheckeod(periph);
518 	if (error) {
519 		xpt_print_path(periph->path);
520 		printf("failed to write terminating filemark(s)\n");
521 		softc->flags |= SA_FLAG_TAPE_FROZEN;
522 	}
523 
524 	/*
525 	 * Whatever we end up doing, allow users to eject tapes from here on.
526 	 */
527 	saprevent(periph, PR_ALLOW);
528 
529 	/*
530 	 * Decide how to end...
531 	 */
532 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0) {
533 		closedbits |= SA_FLAG_TAPE_FROZEN;
534 	} else switch (mode) {
535 	case SA_MODE_OFFLINE:
536 		/*
537 		 * An 'offline' close is an unconditional release of
538 		 * frozen && mount conditions, irrespective of whether
539 		 * these operations succeeded. The reason for this is
540 		 * to allow at least some kind of programmatic way
541 		 * around our state getting all fouled up. If somebody
542 		 * issues an 'offline' command, that will be allowed
543 		 * to clear state.
544 		 */
545 		(void) sarewind(periph);
546 		(void) saloadunload(periph, FALSE);
547 		closedbits |= SA_FLAG_TAPE_MOUNTED|SA_FLAG_TAPE_FROZEN;
548 		break;
549 	case SA_MODE_REWIND:
550 		/*
551 		 * If the rewind fails, return an error- if anyone cares,
552 		 * but not overwriting any previous error.
553 		 *
554 		 * We don't clear the notion of mounted here, but we do
555 		 * clear the notion of frozen if we successfully rewound.
556 		 */
557 		tmp = sarewind(periph);
558 		if (tmp) {
559 			if (error != 0)
560 				error = tmp;
561 		} else {
562 			closedbits |= SA_FLAG_TAPE_FROZEN;
563 		}
564 		break;
565 	case SA_MODE_NOREWIND:
566 		/*
567 		 * If we're not rewinding/unloading the tape, find out
568 		 * whether we need to back up over one of two filemarks
569 		 * we wrote (if we wrote two filemarks) so that appends
570 		 * from this point on will be sane.
571 		 */
572 		if (error == 0 && writing && (softc->quirks & SA_QUIRK_2FM)) {
573 			tmp = saspace(periph, -1, SS_FILEMARKS);
574 			if (tmp) {
575 				xpt_print_path(periph->path);
576 				printf("unable to backspace over one of double"
577 				   " filemarks at end of tape\n");
578 				xpt_print_path(periph->path);
579 				printf("it is possible that this device"
580 				   " needs a SA_QUIRK_1FM quirk set for it\n");
581 				softc->flags |= SA_FLAG_TAPE_FROZEN;
582 			}
583 		}
584 		break;
585 	default:
586 		xpt_print_path(periph->path);
587 		panic("unknown mode 0x%x in saclose\n", mode);
588 		/* NOTREACHED */
589 		break;
590 	}
591 
592 	/*
593 	 * We wish to note here that there are no more filemarks to be written.
594 	 */
595 	softc->filemarks = 0;
596 	softc->flags &= ~SA_FLAG_TAPE_WRITTEN;
597 
598 	/*
599 	 * And we are no longer open for business.
600 	 */
601 	softc->flags &= ~closedbits;
602 
603 	/*
604 	 * Inform users if tape state if frozen....
605 	 */
606 	if (softc->flags & SA_FLAG_TAPE_FROZEN) {
607 		xpt_print_path(periph->path);
608 		printf("tape is now frozen- use an OFFLINE, REWIND or MTEOM "
609 		    "command to clear this state.\n");
610 	}
611 
612 	/* release the device if it is no longer mounted */
613 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0)
614 		sareservereleaseunit(periph, FALSE);
615 
616 	cam_periph_unlock(periph);
617 	cam_periph_release(periph);
618 
619 	return (error);
620 }
621 
622 /*
623  * Actually translate the requested transfer into one the physical driver
624  * can understand.  The transfer is described by a buf and will include
625  * only one physical transfer.
626  */
627 static void
628 sastrategy(struct bio *bp)
629 {
630 	struct cam_periph *periph;
631 	struct sa_softc *softc;
632 	u_int  unit;
633 	int    s;
634 
635 	if (SA_IS_CTRL(bp->bio_dev)) {
636 		bp->bio_error = EINVAL;
637 		goto bad;
638 	}
639 	unit = SAUNIT(bp->bio_dev);
640 	periph = cam_extend_get(saperiphs, unit);
641 	if (periph == NULL) {
642 		bp->bio_error = ENXIO;
643 		goto bad;
644 	}
645 	softc = (struct sa_softc *)periph->softc;
646 
647 	s = splsoftcam();
648 
649 	if (softc->flags & SA_FLAG_INVALID) {
650 		splx(s);
651 		bp->bio_error = ENXIO;
652 		goto bad;
653 	}
654 
655 	if (softc->flags & SA_FLAG_TAPE_FROZEN) {
656 		splx(s);
657 		bp->bio_error = EPERM;
658 		goto bad;
659 	}
660 
661 	splx(s);
662 
663 	/*
664 	 * If it's a null transfer, return immediatly
665 	 */
666 	if (bp->bio_bcount == 0)
667 		goto done;
668 
669 	/* valid request?  */
670 	if (softc->flags & SA_FLAG_FIXED) {
671 		/*
672 		 * Fixed block device.  The byte count must
673 		 * be a multiple of our block size.
674 		 */
675 		if (((softc->blk_mask != ~0) &&
676 		    ((bp->bio_bcount & softc->blk_mask) != 0)) ||
677 		    ((softc->blk_mask == ~0) &&
678 		    ((bp->bio_bcount % softc->min_blk) != 0))) {
679 			xpt_print_path(periph->path);
680 			printf("Invalid request.  Fixed block device "
681 			       "requests must be a multiple "
682 			       "of %d bytes\n", softc->min_blk);
683 			bp->bio_error = EINVAL;
684 			goto bad;
685 		}
686 	} else if ((bp->bio_bcount > softc->max_blk) ||
687 		   (bp->bio_bcount < softc->min_blk) ||
688 		   (bp->bio_bcount & softc->blk_mask) != 0) {
689 
690 		xpt_print_path(periph->path);
691 		printf("Invalid request.  Variable block device "
692 		    "requests must be ");
693 		if (softc->blk_mask != 0) {
694 			printf("a multiple of %d ", (0x1 << softc->blk_gran));
695 		}
696 		printf("between %d and %d bytes\n", softc->min_blk,
697 		    softc->max_blk);
698 		bp->bio_error = EINVAL;
699 		goto bad;
700         }
701 
702 	/*
703 	 * Mask interrupts so that the device cannot be invalidated until
704 	 * after we are in the queue.  Otherwise, we might not properly
705 	 * clean up one of the buffers.
706 	 */
707 	s = splbio();
708 
709 	/*
710 	 * Place it at the end of the queue.
711 	 */
712 	bioq_insert_tail(&softc->bio_queue, bp);
713 
714 	softc->queue_count++;
715 	CAM_DEBUG(periph->path, CAM_DEBUG_INFO, ("sastrategy: enqueuing a %d "
716 	    "%s byte %s queue count now %d\n", (int) bp->bio_bcount,
717 	     (softc->flags & SA_FLAG_FIXED)?  "fixed" : "variable",
718 	     (bp->bio_cmd == BIO_READ)? "read" : "write", softc->queue_count));
719 
720 	splx(s);
721 
722 	/*
723 	 * Schedule ourselves for performing the work.
724 	 */
725 	xpt_schedule(periph, 1);
726 
727 	return;
728 bad:
729 	bp->bio_flags |= BIO_ERROR;
730 done:
731 
732 	/*
733 	 * Correctly set the buf to indicate a completed xfer
734 	 */
735 	bp->bio_resid = bp->bio_bcount;
736 	biodone(bp);
737 }
738 
739 static int
740 saioctl(dev_t dev, u_long cmd, caddr_t arg, int flag, struct proc *p)
741 {
742 	struct cam_periph *periph;
743 	struct sa_softc *softc;
744 	scsi_space_code spaceop;
745 	int didlockperiph = 0;
746 	int s;
747 	int unit;
748 	int mode;
749 	int density;
750 	int error = 0;
751 
752 	unit = SAUNIT(dev);
753 	mode = SAMODE(dev);
754 	density = SADENSITY(dev);
755 	error = 0;		/* shut up gcc */
756 	spaceop = 0;		/* shut up gcc */
757 
758 	periph = cam_extend_get(saperiphs, unit);
759 	if (periph == NULL)
760 		return (ENXIO);
761 
762 	softc = (struct sa_softc *)periph->softc;
763 
764 	/*
765 	 * Check for control mode accesses. We allow MTIOCGET and
766 	 * MTIOCERRSTAT (but need to be the only one open in order
767 	 * to clear latched status), and MTSETBSIZE, MTSETDNSTY
768 	 * and MTCOMP (but need to be the only one accessing this
769 	 * device to run those).
770 	 */
771 
772 	if (SA_IS_CTRL(dev)) {
773 		switch (cmd) {
774 		case MTIOCGETEOTMODEL:
775 		case MTIOCGET:
776 			break;
777 		case MTIOCERRSTAT:
778 			/*
779 			 * If the periph isn't already locked, lock it
780 			 * so our MTIOCERRSTAT can reset latched error stats.
781 			 *
782 			 * If the periph is already locked, skip it because
783 			 * we're just getting status and it'll be up to the
784 			 * other thread that has this device open to do
785 			 * an MTIOCERRSTAT that would clear latched status.
786 			 */
787 			s = splsoftcam();
788 			if ((periph->flags & CAM_PERIPH_LOCKED) == 0) {
789 				error = cam_periph_lock(periph, PRIBIO|PCATCH);
790 				if (error != 0) {
791 					splx(s);
792 					return (error);
793 				}
794 				didlockperiph = 1;
795 			}
796 			break;
797 
798 		case MTIOCSETEOTMODEL:
799 		case MTSETBSIZ:
800 		case MTSETDNSTY:
801 		case MTCOMP:
802 			/*
803 			 * We need to acquire the peripheral here rather
804 			 * than at open time because we are sharing writable
805 			 * access to data structures.
806 			 */
807 			s = splsoftcam();
808 			error = cam_periph_lock(periph, PRIBIO|PCATCH);
809 			if (error != 0) {
810 				splx(s);
811 				return (error);
812 			}
813 			didlockperiph = 1;
814 			break;
815 
816 		default:
817 			return (EINVAL);
818 		}
819 	}
820 
821 	/*
822 	 * Find the device that the user is talking about
823 	 */
824 	switch (cmd) {
825 	case MTIOCGET:
826 	{
827 		struct mtget *g = (struct mtget *)arg;
828 
829 		/*
830 		 * If this isn't the control mode device, actually go out
831 		 * and ask the drive again what it's set to.
832 		 */
833 		if (!SA_IS_CTRL(dev)) {
834 			u_int8_t write_protect;
835 			int comp_enabled, comp_supported;
836 			error = sagetparams(periph, SA_PARAM_ALL,
837 			    &softc->media_blksize, &softc->media_density,
838 			    &softc->media_numblks, &softc->buffer_mode,
839 			    &write_protect, &softc->speed, &comp_supported,
840 			    &comp_enabled, &softc->comp_algorithm, NULL);
841 			if (error)
842 				break;
843 			if (write_protect)
844 				softc->flags |= SA_FLAG_TAPE_WP;
845 			else
846 				softc->flags &= ~SA_FLAG_TAPE_WP;
847 			softc->flags &= ~(SA_FLAG_COMP_SUPP|
848 			    SA_FLAG_COMP_ENABLED|SA_FLAG_COMP_UNSUPP);
849 			if (comp_supported) {
850 				if (softc->saved_comp_algorithm == 0)
851 					softc->saved_comp_algorithm =
852 					    softc->comp_algorithm;
853 				softc->flags |= SA_FLAG_COMP_SUPP;
854 				if (comp_enabled)
855 					softc->flags |= SA_FLAG_COMP_ENABLED;
856 			} else
857 				softc->flags |= SA_FLAG_COMP_UNSUPP;
858 		}
859 		bzero(g, sizeof(struct mtget));
860 		g->mt_type = MT_ISAR;
861 		if (softc->flags & SA_FLAG_COMP_UNSUPP) {
862 			g->mt_comp = MT_COMP_UNSUPP;
863 			g->mt_comp0 = MT_COMP_UNSUPP;
864 			g->mt_comp1 = MT_COMP_UNSUPP;
865 			g->mt_comp2 = MT_COMP_UNSUPP;
866 			g->mt_comp3 = MT_COMP_UNSUPP;
867 		} else {
868 			if ((softc->flags & SA_FLAG_COMP_ENABLED) == 0) {
869 				g->mt_comp = MT_COMP_DISABLED;
870 			} else {
871 				g->mt_comp = softc->comp_algorithm;
872 			}
873 			g->mt_comp0 = softc->comp_algorithm;
874 			g->mt_comp1 = softc->comp_algorithm;
875 			g->mt_comp2 = softc->comp_algorithm;
876 			g->mt_comp3 = softc->comp_algorithm;
877 		}
878 		g->mt_density = softc->media_density;
879 		g->mt_density0 = softc->media_density;
880 		g->mt_density1 = softc->media_density;
881 		g->mt_density2 = softc->media_density;
882 		g->mt_density3 = softc->media_density;
883 		g->mt_blksiz = softc->media_blksize;
884 		g->mt_blksiz0 = softc->media_blksize;
885 		g->mt_blksiz1 = softc->media_blksize;
886 		g->mt_blksiz2 = softc->media_blksize;
887 		g->mt_blksiz3 = softc->media_blksize;
888 		g->mt_fileno = softc->fileno;
889 		g->mt_blkno = softc->blkno;
890 		g->mt_dsreg = (short) softc->dsreg;
891 		error = 0;
892 		break;
893 	}
894 	case MTIOCERRSTAT:
895 	{
896 		struct scsi_tape_errors *sep =
897 		    &((union mterrstat *)arg)->scsi_errstat;
898 
899 		CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
900 		    ("saioctl: MTIOCERRSTAT\n"));
901 
902 		bzero(sep, sizeof(*sep));
903 		sep->io_resid = softc->last_io_resid;
904 		bcopy((caddr_t) &softc->last_io_sense, sep->io_sense,
905 		    sizeof (sep->io_sense));
906 		bcopy((caddr_t) &softc->last_io_cdb, sep->io_cdb,
907 		    sizeof (sep->io_cdb));
908 		sep->ctl_resid = softc->last_ctl_resid;
909 		bcopy((caddr_t) &softc->last_ctl_sense, sep->ctl_sense,
910 		    sizeof (sep->ctl_sense));
911 		bcopy((caddr_t) &softc->last_ctl_cdb, sep->ctl_cdb,
912 		    sizeof (sep->ctl_cdb));
913 
914 		if (SA_IS_CTRL(dev) == 0 || didlockperiph)
915 			bzero((caddr_t) &softc->errinfo,
916 			    sizeof (softc->errinfo));
917 		error = 0;
918 		break;
919 	}
920 	case MTIOCTOP:
921 	{
922 		struct mtop *mt;
923 		int    count;
924 
925 		mt = (struct mtop *)arg;
926 
927 		CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
928 			 ("saioctl: op=0x%x count=0x%x\n",
929 			  mt->mt_op, mt->mt_count));
930 
931 		count = mt->mt_count;
932 		switch (mt->mt_op) {
933 		case MTWEOF:	/* write an end-of-file marker */
934 			/* XXXX: NEED TO CLEAR SA_TAPE_WRITTEN */
935 			error = sawritefilemarks(periph, count, FALSE);
936 			break;
937 		case MTWSS:	/* write a setmark */
938 			error = sawritefilemarks(periph, count, TRUE);
939 			break;
940 		case MTBSR:	/* backward space record */
941 		case MTFSR:	/* forward space record */
942 		case MTBSF:	/* backward space file */
943 		case MTFSF:	/* forward space file */
944 		case MTBSS:	/* backward space setmark */
945 		case MTFSS:	/* forward space setmark */
946 		case MTEOD:	/* space to end of recorded medium */
947 		{
948 			int nmarks;
949 
950 			spaceop = SS_FILEMARKS;
951 			nmarks = softc->filemarks;
952 			error = sacheckeod(periph);
953 			if (error) {
954 				xpt_print_path(periph->path);
955 				printf("EOD check prior to spacing failed\n");
956 				softc->flags |= SA_FLAG_EIO_PENDING;
957 				break;
958 			}
959 			nmarks -= softc->filemarks;
960 			switch(mt->mt_op) {
961 			case MTBSR:
962 				count = -count;
963 				/* FALLTHROUGH */
964 			case MTFSR:
965 				spaceop = SS_BLOCKS;
966 				break;
967 			case MTBSF:
968 				count = -count;
969 				/* FALLTHROUGH */
970 			case MTFSF:
971 				break;
972 			case MTBSS:
973 				count = -count;
974 				/* FALLTHROUGH */
975 			case MTFSS:
976 				spaceop = SS_SETMARKS;
977 				break;
978 			case MTEOD:
979 				spaceop = SS_EOD;
980 				count = 0;
981 				nmarks = 0;
982 				break;
983 			default:
984 				error = EINVAL;
985 				break;
986 			}
987 			if (error)
988 				break;
989 
990 			nmarks = softc->filemarks;
991 			/*
992 			 * XXX: Why are we checking again?
993 			 */
994 			error = sacheckeod(periph);
995 			if (error)
996 				break;
997 			nmarks -= softc->filemarks;
998 			error = saspace(periph, count - nmarks, spaceop);
999 			/*
1000 			 * At this point, clear that we've written the tape
1001 			 * and that we've written any filemarks. We really
1002 			 * don't know what the applications wishes to do next-
1003 			 * the sacheckeod's will make sure we terminated the
1004 			 * tape correctly if we'd been writing, but the next
1005 			 * action the user application takes will set again
1006 			 * whether we need to write filemarks.
1007 			 */
1008 			softc->flags &=
1009 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1010 			softc->filemarks = 0;
1011 			break;
1012 		}
1013 		case MTREW:	/* rewind */
1014 			(void) sacheckeod(periph);
1015 			error = sarewind(periph);
1016 			/* see above */
1017 			softc->flags &=
1018 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1019 			softc->filemarks = 0;
1020 			break;
1021 		case MTERASE:	/* erase */
1022 			error = saerase(periph, count);
1023 			softc->flags &=
1024 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1025 			break;
1026 		case MTRETENS:	/* re-tension tape */
1027 			error = saretension(periph);
1028 			softc->flags &=
1029 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1030 			break;
1031 		case MTOFFL:	/* rewind and put the drive offline */
1032 
1033 			(void) sacheckeod(periph);
1034 			/* see above */
1035 			softc->flags &= ~SA_FLAG_TAPE_WRITTEN;
1036 			softc->filemarks = 0;
1037 
1038 			error = sarewind(periph);
1039 			/* clear the frozen flag anyway */
1040 			softc->flags &= ~SA_FLAG_TAPE_FROZEN;
1041 
1042 			/*
1043 			 * Be sure to allow media removal before ejecting.
1044 			 */
1045 
1046 			saprevent(periph, PR_ALLOW);
1047 			if (error == 0) {
1048 				error = saloadunload(periph, FALSE);
1049 				if (error == 0) {
1050 					softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1051 				}
1052 			}
1053 			break;
1054 
1055 		case MTNOP:	/* no operation, sets status only */
1056 		case MTCACHE:	/* enable controller cache */
1057 		case MTNOCACHE:	/* disable controller cache */
1058 			error = 0;
1059 			break;
1060 
1061 		case MTSETBSIZ:	/* Set block size for device */
1062 
1063 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE, count,
1064 					    0, 0, 0);
1065 			if (error == 0) {
1066 				softc->last_media_blksize =
1067 				    softc->media_blksize;
1068 				softc->media_blksize = count;
1069 				if (count) {
1070 					softc->flags |= SA_FLAG_FIXED;
1071 					if (powerof2(count)) {
1072 						softc->blk_shift =
1073 						    ffs(count) - 1;
1074 						softc->blk_mask = count - 1;
1075 					} else {
1076 						softc->blk_mask = ~0;
1077 						softc->blk_shift = 0;
1078 					}
1079 					/*
1080 					 * Make the user's desire 'persistent'.
1081 					 */
1082 					softc->quirks &= ~SA_QUIRK_VARIABLE;
1083 					softc->quirks |= SA_QUIRK_FIXED;
1084 				} else {
1085 					softc->flags &= ~SA_FLAG_FIXED;
1086 					if (softc->max_blk == 0) {
1087 						softc->max_blk = ~0;
1088 					}
1089 					softc->blk_shift = 0;
1090 					if (softc->blk_gran != 0) {
1091 						softc->blk_mask =
1092 						    softc->blk_gran - 1;
1093 					} else {
1094 						softc->blk_mask = 0;
1095 					}
1096 					/*
1097 					 * Make the user's desire 'persistent'.
1098 					 */
1099 					softc->quirks |= SA_QUIRK_VARIABLE;
1100 					softc->quirks &= ~SA_QUIRK_FIXED;
1101 				}
1102 			}
1103 			break;
1104 		case MTSETDNSTY:	/* Set density for device and mode */
1105 			if (count > UCHAR_MAX) {
1106 				error = EINVAL;
1107 				break;
1108 			} else {
1109 				error = sasetparams(periph, SA_PARAM_DENSITY,
1110 						    0, count, 0, 0);
1111 			}
1112 			break;
1113 		case MTCOMP:	/* enable compression */
1114 			/*
1115 			 * Some devices don't support compression, and
1116 			 * don't like it if you ask them for the
1117 			 * compression page.
1118 			 */
1119 			if ((softc->quirks & SA_QUIRK_NOCOMP) ||
1120 			    (softc->flags & SA_FLAG_COMP_UNSUPP)) {
1121 				error = ENODEV;
1122 				break;
1123 			}
1124 			error = sasetparams(periph, SA_PARAM_COMPRESSION,
1125 			    0, 0, count, SF_NO_PRINT);
1126 			break;
1127 		default:
1128 			error = EINVAL;
1129 		}
1130 		break;
1131 	}
1132 	case MTIOCIEOT:
1133 	case MTIOCEEOT:
1134 		error = 0;
1135 		break;
1136 	case MTIOCRDSPOS:
1137 		error = sardpos(periph, 0, (u_int32_t *) arg);
1138 		break;
1139 	case MTIOCRDHPOS:
1140 		error = sardpos(periph, 1, (u_int32_t *) arg);
1141 		break;
1142 	case MTIOCSLOCATE:
1143 		error = sasetpos(periph, 0, (u_int32_t *) arg);
1144 		break;
1145 	case MTIOCHLOCATE:
1146 		error = sasetpos(periph, 1, (u_int32_t *) arg);
1147 		break;
1148 	case MTIOCGETEOTMODEL:
1149 		error = 0;
1150 		if (softc->quirks & SA_QUIRK_1FM)
1151 			mode = 1;
1152 		else
1153 			mode = 2;
1154 		*((u_int32_t *) arg) = mode;
1155 		break;
1156 	case MTIOCSETEOTMODEL:
1157 		error = 0;
1158 		switch (*((u_int32_t *) arg)) {
1159 		case 1:
1160 			softc->quirks &= ~SA_QUIRK_2FM;
1161 			softc->quirks |= SA_QUIRK_1FM;
1162 			break;
1163 		case 2:
1164 			softc->quirks &= ~SA_QUIRK_1FM;
1165 			softc->quirks |= SA_QUIRK_2FM;
1166 			break;
1167 		default:
1168 			error = EINVAL;
1169 			break;
1170 		}
1171 		break;
1172 	default:
1173 		error = cam_periph_ioctl(periph, cmd, arg, saerror);
1174 		break;
1175 	}
1176 	if (didlockperiph) {
1177 		cam_periph_unlock(periph);
1178 	}
1179 	return (error);
1180 }
1181 
1182 static void
1183 sainit(void)
1184 {
1185 	cam_status status;
1186 	struct cam_path *path;
1187 
1188 	/*
1189 	 * Create our extend array for storing the devices we attach to.
1190 	 */
1191 	saperiphs = cam_extend_new();
1192 	if (saperiphs == NULL) {
1193 		printf("sa: Failed to alloc extend array!\n");
1194 		return;
1195 	}
1196 
1197 	/*
1198 	 * Install a global async callback.
1199 	 */
1200 	status = xpt_create_path(&path, NULL, CAM_XPT_PATH_ID,
1201 				 CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);
1202 
1203 	if (status == CAM_REQ_CMP) {
1204 		/* Register the async callbacks of interrest */
1205 		struct ccb_setasync csa; /*
1206 					  * This is an immediate CCB,
1207 					  * so using the stack is OK
1208 					  */
1209 		xpt_setup_ccb(&csa.ccb_h, path, 5);
1210 		csa.ccb_h.func_code = XPT_SASYNC_CB;
1211 		csa.event_enable = AC_FOUND_DEVICE;
1212 		csa.callback = saasync;
1213 		csa.callback_arg = NULL;
1214 		xpt_action((union ccb *)&csa);
1215 		status = csa.ccb_h.status;
1216 		xpt_free_path(path);
1217 	}
1218 
1219 	if (status != CAM_REQ_CMP) {
1220 		printf("sa: Failed to attach master async callback "
1221 		       "due to status 0x%x!\n", status);
1222 	}
1223 }
1224 
1225 static void
1226 saoninvalidate(struct cam_periph *periph)
1227 {
1228 	struct sa_softc *softc;
1229 	struct bio *q_bp;
1230 	struct ccb_setasync csa;
1231 	int s;
1232 
1233 	softc = (struct sa_softc *)periph->softc;
1234 
1235 	/*
1236 	 * De-register any async callbacks.
1237 	 */
1238 	xpt_setup_ccb(&csa.ccb_h, periph->path,
1239 		      /* priority */ 5);
1240 	csa.ccb_h.func_code = XPT_SASYNC_CB;
1241 	csa.event_enable = 0;
1242 	csa.callback = saasync;
1243 	csa.callback_arg = periph;
1244 	xpt_action((union ccb *)&csa);
1245 
1246 	softc->flags |= SA_FLAG_INVALID;
1247 
1248 	/*
1249 	 * Although the oninvalidate() routines are always called at
1250 	 * splsoftcam, we need to be at splbio() here to keep the buffer
1251 	 * queue from being modified while we traverse it.
1252 	 */
1253 	s = splbio();
1254 
1255 	/*
1256 	 * Return all queued I/O with ENXIO.
1257 	 * XXX Handle any transactions queued to the card
1258 	 *     with XPT_ABORT_CCB.
1259 	 */
1260 	while ((q_bp = bioq_first(&softc->bio_queue)) != NULL){
1261 		bioq_remove(&softc->bio_queue, q_bp);
1262 		q_bp->bio_resid = q_bp->bio_bcount;
1263 		q_bp->bio_error = ENXIO;
1264 		q_bp->bio_flags |= BIO_ERROR;
1265 		biodone(q_bp);
1266 	}
1267 	softc->queue_count = 0;
1268 	splx(s);
1269 
1270 	xpt_print_path(periph->path);
1271 	printf("lost device\n");
1272 
1273 }
1274 
1275 static void
1276 sacleanup(struct cam_periph *periph)
1277 {
1278 	struct sa_softc *softc;
1279 	int i;
1280 
1281 	softc = (struct sa_softc *)periph->softc;
1282 
1283 	devstat_remove_entry(&softc->device_stats);
1284 
1285 	destroy_dev(softc->devs.ctl_dev);
1286 	destroy_dev(softc->devs.r_dev);
1287 	destroy_dev(softc->devs.nr_dev);
1288 	destroy_dev(softc->devs.er_dev);
1289 
1290 	for (i = 0; i < SA_NUM_MODES; i++) {
1291 		destroy_dev(softc->devs.mode_devs[i].r_dev);
1292 		destroy_dev(softc->devs.mode_devs[i].nr_dev);
1293 		destroy_dev(softc->devs.mode_devs[i].er_dev);
1294 	}
1295 
1296 	cam_extend_release(saperiphs, periph->unit_number);
1297 	xpt_print_path(periph->path);
1298 	printf("removing device entry\n");
1299 	free(softc, M_DEVBUF);
1300 }
1301 
1302 static void
1303 saasync(void *callback_arg, u_int32_t code,
1304 	struct cam_path *path, void *arg)
1305 {
1306 	struct cam_periph *periph;
1307 
1308 	periph = (struct cam_periph *)callback_arg;
1309 	switch (code) {
1310 	case AC_FOUND_DEVICE:
1311 	{
1312 		struct ccb_getdev *cgd;
1313 		cam_status status;
1314 
1315 		cgd = (struct ccb_getdev *)arg;
1316 
1317 		if (SID_TYPE(&cgd->inq_data) != T_SEQUENTIAL)
1318 			break;
1319 
1320 		/*
1321 		 * Allocate a peripheral instance for
1322 		 * this device and start the probe
1323 		 * process.
1324 		 */
1325 		status = cam_periph_alloc(saregister, saoninvalidate,
1326 					  sacleanup, sastart,
1327 					  "sa", CAM_PERIPH_BIO, cgd->ccb_h.path,
1328 					  saasync, AC_FOUND_DEVICE, cgd);
1329 
1330 		if (status != CAM_REQ_CMP
1331 		 && status != CAM_REQ_INPROG)
1332 			printf("saasync: Unable to probe new device "
1333 				"due to status 0x%x\n", status);
1334 		break;
1335 	}
1336 	default:
1337 		cam_periph_async(periph, code, path, arg);
1338 		break;
1339 	}
1340 }
1341 
1342 static cam_status
1343 saregister(struct cam_periph *periph, void *arg)
1344 {
1345 	struct sa_softc *softc;
1346 	struct ccb_setasync csa;
1347 	struct ccb_getdev *cgd;
1348 	caddr_t match;
1349 	int i;
1350 
1351 	cgd = (struct ccb_getdev *)arg;
1352 	if (periph == NULL) {
1353 		printf("saregister: periph was NULL!!\n");
1354 		return (CAM_REQ_CMP_ERR);
1355 	}
1356 
1357 	if (cgd == NULL) {
1358 		printf("saregister: no getdev CCB, can't register device\n");
1359 		return (CAM_REQ_CMP_ERR);
1360 	}
1361 
1362 	softc = (struct sa_softc *)malloc(sizeof (*softc), M_DEVBUF, M_NOWAIT);
1363 	if (softc == NULL) {
1364 		printf("saregister: Unable to probe new device. "
1365 		       "Unable to allocate softc\n");
1366 		return (CAM_REQ_CMP_ERR);
1367 	}
1368 
1369 	bzero(softc, sizeof(*softc));
1370 	softc->scsi_rev = SID_ANSI_REV(&cgd->inq_data);
1371 	softc->state = SA_STATE_NORMAL;
1372 	softc->fileno = (daddr_t) -1;
1373 	softc->blkno = (daddr_t) -1;
1374 
1375 	bioq_init(&softc->bio_queue);
1376 	periph->softc = softc;
1377 	cam_extend_set(saperiphs, periph->unit_number, periph);
1378 
1379 	/*
1380 	 * See if this device has any quirks.
1381 	 */
1382 	match = cam_quirkmatch((caddr_t)&cgd->inq_data,
1383 			       (caddr_t)sa_quirk_table,
1384 			       sizeof(sa_quirk_table)/sizeof(*sa_quirk_table),
1385 			       sizeof(*sa_quirk_table), scsi_inquiry_match);
1386 
1387 	if (match != NULL) {
1388 		softc->quirks = ((struct sa_quirk_entry *)match)->quirks;
1389 		softc->last_media_blksize =
1390 		    ((struct sa_quirk_entry *)match)->prefblk;
1391 #ifdef	CAMDEBUG
1392 		xpt_print_path(periph->path);
1393 		printf("found quirk entry %d\n", (int)
1394 		    (((struct sa_quirk_entry *) match) - sa_quirk_table));
1395 #endif
1396 	} else
1397 		softc->quirks = SA_QUIRK_NONE;
1398 
1399 	/*
1400  	 * The SA driver supports a blocksize, but we don't know the
1401 	 * blocksize until we media is inserted.  So, set a flag to
1402 	 * indicate that the blocksize is unavailable right now.
1403 	 */
1404 	devstat_add_entry(&softc->device_stats, "sa", periph->unit_number, 0,
1405 	    DEVSTAT_BS_UNAVAILABLE, SID_TYPE(&cgd->inq_data) |
1406 	    DEVSTAT_TYPE_IF_SCSI, DEVSTAT_PRIORITY_TAPE);
1407 
1408 	softc->devs.ctl_dev = make_dev(&sa_cdevsw, SAMINOR(SA_CTLDEV,
1409 	    periph->unit_number, 0, SA_ATYPE_R), UID_ROOT, GID_OPERATOR,
1410 	    0660, "r%s%d.ctl", periph->periph_name, periph->unit_number);
1411 
1412 	softc->devs.r_dev = make_dev(&sa_cdevsw, SAMINOR(SA_NOT_CTLDEV,
1413 	    periph->unit_number, 0, SA_ATYPE_R), UID_ROOT, GID_OPERATOR,
1414 	    0660, "r%s%d", periph->periph_name, periph->unit_number);
1415 
1416 	softc->devs.nr_dev = make_dev(&sa_cdevsw, SAMINOR(SA_NOT_CTLDEV,
1417 	    periph->unit_number, 0, SA_ATYPE_NR), UID_ROOT, GID_OPERATOR,
1418 	    0660, "nr%s%d", periph->periph_name, periph->unit_number);
1419 
1420 	softc->devs.er_dev = make_dev(&sa_cdevsw, SAMINOR(SA_NOT_CTLDEV,
1421 	    periph->unit_number, 0, SA_ATYPE_ER), UID_ROOT, GID_OPERATOR,
1422 	    0660, "er%s%d", periph->periph_name, periph->unit_number);
1423 
1424 	for (i = 0; i < SA_NUM_MODES; i++) {
1425 
1426 		softc->devs.mode_devs[i].r_dev = make_dev(&sa_cdevsw,
1427 		    SAMINOR(SA_NOT_CTLDEV, periph->unit_number, i, SA_ATYPE_R),
1428 		    UID_ROOT, GID_OPERATOR, 0660, "r%s%d.%d",
1429 		    periph->periph_name, periph->unit_number, i);
1430 
1431 		softc->devs.mode_devs[i].nr_dev = make_dev(&sa_cdevsw,
1432 		    SAMINOR(SA_NOT_CTLDEV, periph->unit_number, i, SA_ATYPE_NR),
1433 		    UID_ROOT, GID_OPERATOR, 0660, "nr%s%d.%d",
1434 		    periph->periph_name, periph->unit_number, i);
1435 
1436 
1437 		softc->devs.mode_devs[i].er_dev = make_dev(&sa_cdevsw,
1438 		    SAMINOR(SA_NOT_CTLDEV, periph->unit_number, i, SA_ATYPE_ER),
1439 		    UID_ROOT, GID_OPERATOR, 0660, "er%s%d.%d",
1440 		    periph->periph_name, periph->unit_number, i);
1441 	}
1442 
1443 	/*
1444 	 * Add an async callback so that we get
1445 	 * notified if this device goes away.
1446 	 */
1447 	xpt_setup_ccb(&csa.ccb_h, periph->path, /* priority */ 5);
1448 	csa.ccb_h.func_code = XPT_SASYNC_CB;
1449 	csa.event_enable = AC_LOST_DEVICE;
1450 	csa.callback = saasync;
1451 	csa.callback_arg = periph;
1452 	xpt_action((union ccb *)&csa);
1453 
1454 	xpt_announce_periph(periph, NULL);
1455 
1456 	return (CAM_REQ_CMP);
1457 }
1458 
1459 static void
1460 sastart(struct cam_periph *periph, union ccb *start_ccb)
1461 {
1462 	struct sa_softc *softc;
1463 
1464 	softc = (struct sa_softc *)periph->softc;
1465 
1466 	CAM_DEBUG(periph->path, CAM_DEBUG_INFO, ("sastart"));
1467 
1468 	switch (softc->state) {
1469 	case SA_STATE_NORMAL:
1470 	{
1471 		/* Pull a buffer from the queue and get going on it */
1472 		struct bio *bp;
1473 		int s;
1474 
1475 		/*
1476 		 * See if there is a buf with work for us to do..
1477 		 */
1478 		s = splbio();
1479 		bp = bioq_first(&softc->bio_queue);
1480 		if (periph->immediate_priority <= periph->pinfo.priority) {
1481 			CAM_DEBUG_PRINT(CAM_DEBUG_SUBTRACE,
1482 					("queuing for immediate ccb\n"));
1483 			start_ccb->ccb_h.ccb_type = SA_CCB_WAITING;
1484 			SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
1485 					  periph_links.sle);
1486 			periph->immediate_priority = CAM_PRIORITY_NONE;
1487 			splx(s);
1488 			wakeup(&periph->ccb_list);
1489 		} else if (bp == NULL) {
1490 			splx(s);
1491 			xpt_release_ccb(start_ccb);
1492 		} else if ((softc->flags & SA_FLAG_ERR_PENDING) != 0) {
1493 			struct bio *done_bp;
1494 			softc->queue_count--;
1495 			bioq_remove(&softc->bio_queue, bp);
1496 			bp->bio_resid = bp->bio_bcount;
1497 			bp->bio_flags |= BIO_ERROR;
1498 			if ((softc->flags & SA_FLAG_EOM_PENDING) != 0) {
1499 				if (bp->bio_cmd == BIO_WRITE)
1500 					bp->bio_error = ENOSPC;
1501 				else
1502 					bp->bio_error = EIO;
1503 			}
1504 			if ((softc->flags & SA_FLAG_EOF_PENDING) != 0) {
1505 				bp->bio_error = EIO;
1506 			}
1507 			if ((softc->flags & SA_FLAG_EIO_PENDING) != 0) {
1508 				bp->bio_error = EIO;
1509 			}
1510 			done_bp = bp;
1511 			bp = bioq_first(&softc->bio_queue);
1512 			/*
1513 			 * Only if we have no other buffers queued up
1514 			 * do we clear the pending error flag.
1515 			 */
1516 			if (bp == NULL)
1517 				softc->flags &= ~SA_FLAG_ERR_PENDING;
1518 			CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
1519 			    ("sastart- ERR_PENDING now 0x%x, bp is %sNULL, "
1520 			    "%d more buffers queued up\n",
1521 			    (softc->flags & SA_FLAG_ERR_PENDING),
1522 			    (bp != NULL)? "not " : " ", softc->queue_count));
1523 			splx(s);
1524 			xpt_release_ccb(start_ccb);
1525 			biodone(done_bp);
1526 		} else {
1527 			u_int32_t length;
1528 
1529 			bioq_remove(&softc->bio_queue, bp);
1530 			softc->queue_count--;
1531 
1532 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
1533 				if (softc->blk_shift != 0) {
1534 					length =
1535 					    bp->bio_bcount >> softc->blk_shift;
1536 				} else if (softc->media_blksize != 0) {
1537 					length =
1538 					    bp->bio_bcount / softc->media_blksize;
1539 				} else {
1540 					bp->bio_error = EIO;
1541 					xpt_print_path(periph->path);
1542 					printf("zero blocksize for "
1543 					    "FIXED length writes?\n");
1544 					splx(s);
1545 					biodone(bp);
1546 					break;
1547 				}
1548 				CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
1549 				    ("Fixed Record Count is %d\n", length));
1550 			} else {
1551 				length = bp->bio_bcount;
1552 				CAM_DEBUG(start_ccb->ccb_h.path, CAM_DEBUG_INFO,
1553 				    ("Variable Record Count is %d\n", length));
1554 			}
1555 			devstat_start_transaction(&softc->device_stats);
1556 			/*
1557 			 * Some people have theorized that we should
1558 			 * suppress illegal length indication if we are
1559 			 * running in variable block mode so that we don't
1560 			 * have to request sense every time our requested
1561 			 * block size is larger than the written block.
1562 			 * The residual information from the ccb allows
1563 			 * us to identify this situation anyway.  The only
1564 			 * problem with this is that we will not get
1565 			 * information about blocks that are larger than
1566 			 * our read buffer unless we set the block size
1567 			 * in the mode page to something other than 0.
1568 			 *
1569 			 * I believe that this is a non-issue. If user apps
1570 			 * don't adjust their read size to match our record
1571 			 * size, that's just life. Anyway, the typical usage
1572 			 * would be to issue, e.g., 64KB reads and occasionally
1573 			 * have to do deal with 512 byte or 1KB intermediate
1574 			 * records.
1575 			 */
1576 			softc->dsreg = (bp->bio_cmd == BIO_READ)?
1577 			    MTIO_DSREG_RD : MTIO_DSREG_WR;
1578 			scsi_sa_read_write(&start_ccb->csio, 0, sadone,
1579 			    MSG_SIMPLE_Q_TAG, (bp->bio_cmd == BIO_READ),
1580 			    FALSE, (softc->flags & SA_FLAG_FIXED) != 0,
1581 			    length, bp->bio_data, bp->bio_bcount, SSD_FULL_SIZE,
1582 			    120 * 60 * 1000);
1583 			start_ccb->ccb_h.ccb_type = SA_CCB_BUFFER_IO;
1584 			start_ccb->ccb_h.ccb_bp = bp;
1585 			bp = bioq_first(&softc->bio_queue);
1586 			splx(s);
1587 			xpt_action(start_ccb);
1588 		}
1589 
1590 		if (bp != NULL) {
1591 			/* Have more work to do, so ensure we stay scheduled */
1592 			xpt_schedule(periph, 1);
1593 		}
1594 		break;
1595 	}
1596 	case SA_STATE_ABNORMAL:
1597 	default:
1598 		panic("state 0x%x in sastart", softc->state);
1599 		break;
1600 	}
1601 }
1602 
1603 
1604 static void
1605 sadone(struct cam_periph *periph, union ccb *done_ccb)
1606 {
1607 	struct sa_softc *softc;
1608 	struct ccb_scsiio *csio;
1609 
1610 	softc = (struct sa_softc *)periph->softc;
1611 	csio = &done_ccb->csio;
1612 	switch (csio->ccb_h.ccb_type) {
1613 	case SA_CCB_BUFFER_IO:
1614 	{
1615 		struct bio *bp;
1616 		int error;
1617 
1618 		softc->dsreg = MTIO_DSREG_REST;
1619 		bp = (struct bio *)done_ccb->ccb_h.ccb_bp;
1620 		error = 0;
1621 		if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
1622 			if ((error = saerror(done_ccb, 0, 0)) == ERESTART) {
1623 				/*
1624 				 * A retry was scheduled, so just return.
1625 				 */
1626 				return;
1627 			}
1628 		}
1629 
1630 		if (error == EIO) {
1631 			int s;
1632 			struct bio *q_bp;
1633 
1634 			/*
1635 			 * Catastrophic error. Mark the tape as frozen
1636 			 * (we no longer know tape position).
1637 			 *
1638 			 * Return all queued I/O with EIO, and unfreeze
1639 			 * our queue so that future transactions that
1640 			 * attempt to fix this problem can get to the
1641 			 * device.
1642 			 *
1643 			 */
1644 
1645 			s = splbio();
1646 			softc->flags |= SA_FLAG_TAPE_FROZEN;
1647 			while ((q_bp = bioq_first(&softc->bio_queue)) != NULL) {
1648 				bioq_remove(&softc->bio_queue, q_bp);
1649 				q_bp->bio_resid = q_bp->bio_bcount;
1650 				q_bp->bio_error = EIO;
1651 				q_bp->bio_flags |= BIO_ERROR;
1652 				biodone(q_bp);
1653 			}
1654 			splx(s);
1655 		}
1656 		if (error != 0) {
1657 			bp->bio_resid = bp->bio_bcount;
1658 			bp->bio_error = error;
1659 			bp->bio_flags |= BIO_ERROR;
1660 			/*
1661 			 * In the error case, position is updated in saerror.
1662 			 */
1663 		} else {
1664 			bp->bio_resid = csio->resid;
1665 			bp->bio_error = 0;
1666 			if (csio->resid != 0) {
1667 				bp->bio_flags |= BIO_ERROR;
1668 			}
1669 			if (bp->bio_cmd == BIO_WRITE) {
1670 				softc->flags |= SA_FLAG_TAPE_WRITTEN;
1671 				softc->filemarks = 0;
1672 			}
1673 			if (softc->blkno != (daddr_t) -1) {
1674 				if ((softc->flags & SA_FLAG_FIXED) != 0) {
1675 					u_int32_t l;
1676 					if (softc->blk_shift != 0) {
1677 						l = bp->bio_bcount >>
1678 							softc->blk_shift;
1679 					} else {
1680 						l = bp->bio_bcount /
1681 							softc->media_blksize;
1682 					}
1683 					softc->blkno += (daddr_t) l;
1684 				} else {
1685 					softc->blkno++;
1686 				}
1687 			}
1688 		}
1689 		/*
1690 		 * If we had an error (immediate or pending),
1691 		 * release the device queue now.
1692 		 */
1693 		if (error || (softc->flags & SA_FLAG_ERR_PENDING))
1694 			cam_release_devq(done_ccb->ccb_h.path, 0, 0, 0, 0);
1695 #ifdef	CAMDEBUG
1696 		if (error || bp->bio_resid) {
1697 			CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
1698 			    	  ("error %d resid %ld count %ld\n", error,
1699 				  bp->bio_resid, bp->bio_bcount));
1700 		}
1701 #endif
1702 		devstat_end_transaction_bio(&softc->device_stats, bp);
1703 		biodone(bp);
1704 		break;
1705 	}
1706 	case SA_CCB_WAITING:
1707 	{
1708 		/* Caller will release the CCB */
1709 		wakeup(&done_ccb->ccb_h.cbfcnp);
1710 		return;
1711 	}
1712 	}
1713 	xpt_release_ccb(done_ccb);
1714 }
1715 
1716 /*
1717  * Mount the tape (make sure it's ready for I/O).
1718  */
1719 static int
1720 samount(struct cam_periph *periph, int oflags, dev_t dev)
1721 {
1722 	struct	sa_softc *softc;
1723 	union	ccb *ccb;
1724 	int	error;
1725 
1726 	/*
1727 	 * oflags can be checked for 'kind' of open (read-only check) - later
1728 	 * dev can be checked for a control-mode or compression open - later
1729 	 */
1730 	UNUSED_PARAMETER(oflags);
1731 	UNUSED_PARAMETER(dev);
1732 
1733 
1734 	softc = (struct sa_softc *)periph->softc;
1735 
1736 	/*
1737 	 * This should determine if something has happend since the last
1738 	 * open/mount that would invalidate the mount. We do *not* want
1739 	 * to retry this command- we just want the status. But we only
1740 	 * do this if we're mounted already- if we're not mounted,
1741 	 * we don't care about the unit read state and can instead use
1742 	 * this opportunity to attempt to reserve the tape unit.
1743 	 */
1744 
1745 	if (softc->flags & SA_FLAG_TAPE_MOUNTED) {
1746 		ccb = cam_periph_getccb(periph, 1);
1747 		scsi_test_unit_ready(&ccb->csio, 0, sadone,
1748 		    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, 5 * 60 * 1000);
1749 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1750 		    &softc->device_stats);
1751 		QFRLS(ccb);
1752 		if (error == ENXIO) {
1753 			softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1754 			scsi_test_unit_ready(&ccb->csio, 0, sadone,
1755 			    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, 5 * 60 * 1000);
1756 			error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1757 			    &softc->device_stats);
1758 			QFRLS(ccb);
1759 		} else if (error) {
1760 			/*
1761 			 * We don't need to freeze the tape because we
1762 			 * will now attempt to rewind/load it.
1763 			 */
1764 			softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1765 			if (CAM_DEBUGGED(ccb->ccb_h.path, CAM_DEBUG_INFO)) {
1766 				xpt_print_path(ccb->ccb_h.path);
1767 				printf("error %d on TUR in samount\n", error);
1768 			}
1769 		}
1770 	} else {
1771 		error = sareservereleaseunit(periph, TRUE);
1772 		if (error) {
1773 			return (error);
1774 		}
1775 		ccb = cam_periph_getccb(periph, 1);
1776 		scsi_test_unit_ready(&ccb->csio, 0, sadone,
1777 		    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, 5 * 60 * 1000);
1778 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1779 		    &softc->device_stats);
1780 		QFRLS(ccb);
1781 	}
1782 
1783 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0) {
1784 		struct scsi_read_block_limits_data *rblim = NULL;
1785 		int comp_enabled, comp_supported;
1786 		u_int8_t write_protect, guessing = 0;
1787 
1788 		/*
1789 		 * Clear out old state.
1790 		 */
1791 		softc->flags &= ~(SA_FLAG_TAPE_WP|SA_FLAG_TAPE_WRITTEN|
1792 				  SA_FLAG_ERR_PENDING|SA_FLAG_COMP_ENABLED|
1793 				  SA_FLAG_COMP_SUPP|SA_FLAG_COMP_UNSUPP);
1794 		softc->filemarks = 0;
1795 
1796 		/*
1797 		 * *Very* first off, make sure we're loaded to BOT.
1798 		 */
1799 		scsi_load_unload(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
1800 		    FALSE, FALSE, 1, SSD_FULL_SIZE, REWIND_TIMEOUT);
1801 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1802 		    &softc->device_stats);
1803 		QFRLS(ccb);
1804 
1805 		/*
1806 		 * In case this doesn't work, do a REWIND instead
1807 		 */
1808 		if (error) {
1809 			scsi_rewind(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG,
1810 			    FALSE, SSD_FULL_SIZE, REWIND_TIMEOUT);
1811 			error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1812 				&softc->device_stats);
1813 			QFRLS(ccb);
1814 		}
1815 		if (error) {
1816 			xpt_release_ccb(ccb);
1817 			goto exit;
1818 		}
1819 
1820 		/*
1821 		 * Do a dummy test read to force access to the
1822 		 * media so that the drive will really know what's
1823 		 * there. We actually don't really care what the
1824 		 * blocksize on tape is and don't expect to really
1825 		 * read a full record.
1826 		 */
1827 		rblim = (struct  scsi_read_block_limits_data *)
1828 		    malloc(8192, M_TEMP, M_WAITOK);
1829 		if (rblim == NULL) {
1830 			xpt_print_path(ccb->ccb_h.path);
1831 			printf("no memory for test read\n");
1832 			xpt_release_ccb(ccb);
1833 			error = ENOMEM;
1834 			goto exit;
1835 		}
1836 
1837 		if ((softc->quirks & SA_QUIRK_NODREAD) == 0) {
1838 			scsi_sa_read_write(&ccb->csio, 0, sadone,
1839 			    MSG_SIMPLE_Q_TAG, 1, FALSE, 0, 8192,
1840 			    (void *) rblim, 8192, SSD_FULL_SIZE,
1841 			    120 * 60 * 1000);
1842 			(void) cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1843 			    &softc->device_stats);
1844 			QFRLS(ccb);
1845 			scsi_rewind(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
1846 			    FALSE, SSD_FULL_SIZE, REWIND_TIMEOUT);
1847 			error = cam_periph_runccb(ccb, saerror, 0,
1848 			    SF_NO_PRINT | SF_RETRY_SELTO | SF_RETRY_UA,
1849 			    &softc->device_stats);
1850 			QFRLS(ccb);
1851 			if (error) {
1852 				xpt_print_path(ccb->ccb_h.path);
1853 				printf("unable to rewind after test read\n");
1854 				xpt_release_ccb(ccb);
1855 				goto exit;
1856 			}
1857 		}
1858 
1859 		/*
1860 		 * Next off, determine block limits.
1861 		 */
1862 		scsi_read_block_limits(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG,
1863 		    rblim, SSD_FULL_SIZE, 5000);
1864 
1865 		error = cam_periph_runccb(ccb, saerror, 0,
1866 		    SF_NO_PRINT | SF_RETRY_UA | SF_RETRY_SELTO,
1867 		    &softc->device_stats);
1868 		QFRLS(ccb);
1869 		xpt_release_ccb(ccb);
1870 
1871 		if (error != 0) {
1872 			/*
1873 			 * If it's less than SCSI-2, READ BLOCK LIMITS is not
1874 			 * a MANDATORY command. Anyway- it doesn't matter-
1875 			 * we can proceed anyway.
1876 			 */
1877 			softc->blk_gran = 0;
1878 			softc->max_blk = ~0;
1879 			softc->min_blk = 0;
1880 		} else {
1881 			if (softc->scsi_rev >= SCSI_REV_3) {
1882 				softc->blk_gran = RBL_GRAN(rblim);
1883 			} else {
1884 				softc->blk_gran = 0;
1885 			}
1886 			/*
1887 			 * We take max_blk == min_blk to mean a default to
1888 			 * fixed mode- but note that whatever we get out of
1889 			 * sagetparams below will actually determine whether
1890 			 * we are actually *in* fixed mode.
1891 			 */
1892 			softc->max_blk = scsi_3btoul(rblim->maximum);
1893 			softc->min_blk = scsi_2btoul(rblim->minimum);
1894 
1895 
1896 		}
1897 		/*
1898 		 * Next, perform a mode sense to determine
1899 		 * current density, blocksize, compression etc.
1900 		 */
1901 		error = sagetparams(periph, SA_PARAM_ALL,
1902 				    &softc->media_blksize,
1903 				    &softc->media_density,
1904 				    &softc->media_numblks,
1905 				    &softc->buffer_mode, &write_protect,
1906 				    &softc->speed, &comp_supported,
1907 				    &comp_enabled, &softc->comp_algorithm,
1908 				    NULL);
1909 
1910 		if (error != 0) {
1911 			/*
1912 			 * We could work a little harder here. We could
1913 			 * adjust our attempts to get information. It
1914 			 * might be an ancient tape drive. If someone
1915 			 * nudges us, we'll do that.
1916 			 */
1917 			goto exit;
1918 		}
1919 
1920 		/*
1921 		 * If no quirk has determined that this is a device that is
1922 		 * preferred to be in fixed or variable mode, now is the time
1923 		 * to find out.
1924 	 	 */
1925 		if ((softc->quirks & (SA_QUIRK_FIXED|SA_QUIRK_VARIABLE)) == 0) {
1926 			guessing = 1;
1927 			/*
1928 			 * This could be expensive to find out. Luckily we
1929 			 * only need to do this once. If we start out in
1930 			 * 'default' mode, try and set ourselves to one
1931 			 * of the densities that would determine a wad
1932 			 * of other stuff. Go from highest to lowest.
1933 			 */
1934 			if (softc->media_density == SCSI_DEFAULT_DENSITY) {
1935 				int i;
1936 				static u_int8_t ctry[] = {
1937 					SCSI_DENSITY_HALFINCH_PE,
1938 					SCSI_DENSITY_HALFINCH_6250C,
1939 					SCSI_DENSITY_HALFINCH_6250,
1940 					SCSI_DENSITY_HALFINCH_1600,
1941 					SCSI_DENSITY_HALFINCH_800,
1942 					SCSI_DENSITY_QIC_4GB,
1943 					SCSI_DENSITY_QIC_2GB,
1944 					SCSI_DENSITY_QIC_525_320,
1945 					SCSI_DENSITY_QIC_150,
1946 					SCSI_DENSITY_QIC_120,
1947 					SCSI_DENSITY_QIC_24,
1948 					SCSI_DENSITY_QIC_11_9TRK,
1949 					SCSI_DENSITY_QIC_11_4TRK,
1950 					SCSI_DENSITY_QIC_1320,
1951 					SCSI_DENSITY_QIC_3080,
1952 					0
1953 				};
1954 				for (i = 0; ctry[i]; i++) {
1955 					error = sasetparams(periph,
1956 					    SA_PARAM_DENSITY, 0, ctry[i],
1957 					    0, SF_NO_PRINT);
1958 					if (error == 0) {
1959 						softc->media_density = ctry[i];
1960 						break;
1961 					}
1962 				}
1963 			}
1964 			switch (softc->media_density) {
1965 			case SCSI_DENSITY_QIC_11_4TRK:
1966 			case SCSI_DENSITY_QIC_11_9TRK:
1967 			case SCSI_DENSITY_QIC_24:
1968 			case SCSI_DENSITY_QIC_120:
1969 			case SCSI_DENSITY_QIC_150:
1970 			case SCSI_DENSITY_QIC_1320:
1971 			case SCSI_DENSITY_QIC_3080:
1972 				softc->quirks &= ~SA_QUIRK_2FM;
1973 				softc->quirks |= SA_QUIRK_FIXED|SA_QUIRK_1FM;
1974 				softc->last_media_blksize = 512;
1975 				break;
1976 			case SCSI_DENSITY_QIC_4GB:
1977 			case SCSI_DENSITY_QIC_2GB:
1978 			case SCSI_DENSITY_QIC_525_320:
1979 				softc->quirks &= ~SA_QUIRK_2FM;
1980 				softc->quirks |= SA_QUIRK_FIXED|SA_QUIRK_1FM;
1981 				softc->last_media_blksize = 1024;
1982 				break;
1983 			default:
1984 				softc->last_media_blksize =
1985 				    softc->media_blksize;
1986 				softc->quirks |= SA_QUIRK_VARIABLE;
1987 				break;
1988 			}
1989 		}
1990 
1991 		/*
1992 		 * If no quirk has determined that this is a device that needs
1993 		 * to have 2 Filemarks at EOD, now is the time to find out.
1994 		 */
1995 
1996 		if ((softc->quirks & SA_QUIRK_2FM) == 0) {
1997 			switch (softc->media_density) {
1998 			case SCSI_DENSITY_HALFINCH_800:
1999 			case SCSI_DENSITY_HALFINCH_1600:
2000 			case SCSI_DENSITY_HALFINCH_6250:
2001 			case SCSI_DENSITY_HALFINCH_6250C:
2002 			case SCSI_DENSITY_HALFINCH_PE:
2003 				softc->quirks &= ~SA_QUIRK_1FM;
2004 				softc->quirks |= SA_QUIRK_2FM;
2005 				break;
2006 			default:
2007 				break;
2008 			}
2009 		}
2010 
2011 		/*
2012 		 * Now validate that some info we got makes sense.
2013 		 */
2014 		if ((softc->max_blk < softc->media_blksize) ||
2015 		    (softc->min_blk > softc->media_blksize &&
2016 		    softc->media_blksize)) {
2017 			xpt_print_path(ccb->ccb_h.path);
2018 			printf("BLOCK LIMITS (%d..%d) could not match current "
2019 			    "block settings (%d)- adjusting\n", softc->min_blk,
2020 			    softc->max_blk, softc->media_blksize);
2021 			softc->max_blk = softc->min_blk =
2022 			    softc->media_blksize;
2023 		}
2024 
2025 		/*
2026 		 * Now put ourselves into the right frame of mind based
2027 		 * upon quirks...
2028 		 */
2029 tryagain:
2030 		/*
2031 		 * If we want to be in FIXED mode and our current blocksize
2032 		 * is not equal to our last blocksize (if nonzero), try and
2033 		 * set ourselves to this last blocksize (as the 'preferred'
2034 		 * block size).  The initial quirkmatch at registry sets the
2035 		 * initial 'last' blocksize. If, for whatever reason, this
2036 		 * 'last' blocksize is zero, set the blocksize to 512,
2037 		 * or min_blk if that's larger.
2038 		 */
2039 		if ((softc->quirks & SA_QUIRK_FIXED) &&
2040 		    (softc->quirks & SA_QUIRK_NO_MODESEL) == 0 &&
2041 		    (softc->media_blksize != softc->last_media_blksize)) {
2042 			softc->media_blksize = softc->last_media_blksize;
2043 			if (softc->media_blksize == 0) {
2044 				softc->media_blksize = 512;
2045 				if (softc->media_blksize < softc->min_blk) {
2046 					softc->media_blksize = softc->min_blk;
2047 				}
2048 			}
2049 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE,
2050 			    softc->media_blksize, 0, 0, SF_NO_PRINT);
2051 			if (error) {
2052 				xpt_print_path(ccb->ccb_h.path);
2053 				printf("unable to set fixed blocksize to %d\n",
2054 				     softc->media_blksize);
2055 				goto exit;
2056 			}
2057 		}
2058 
2059 		if ((softc->quirks & SA_QUIRK_VARIABLE) &&
2060 		    (softc->media_blksize != 0)) {
2061 			softc->last_media_blksize = softc->media_blksize;
2062 			softc->media_blksize = 0;
2063 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE,
2064 			    0, 0, 0, SF_NO_PRINT);
2065 			if (error) {
2066 				/*
2067 				 * If this fails and we were guessing, just
2068 				 * assume that we got it wrong and go try
2069 				 * fixed block mode. Don't even check against
2070 				 * density code at this point.
2071 				 */
2072 				if (guessing) {
2073 					softc->quirks &= ~SA_QUIRK_VARIABLE;
2074 					softc->quirks |= SA_QUIRK_FIXED;
2075 					if (softc->last_media_blksize == 0)
2076 						softc->last_media_blksize = 512;
2077 					goto tryagain;
2078 				}
2079 				xpt_print_path(ccb->ccb_h.path);
2080 				printf("unable to set variable blocksize\n");
2081 				goto exit;
2082 			}
2083 		}
2084 
2085 		/*
2086 		 * Now that we have the current block size,
2087 		 * set up some parameters for sastart's usage.
2088 		 */
2089 		if (softc->media_blksize) {
2090 			softc->flags |= SA_FLAG_FIXED;
2091 			if (powerof2(softc->media_blksize)) {
2092 				softc->blk_shift =
2093 				    ffs(softc->media_blksize) - 1;
2094 				softc->blk_mask = softc->media_blksize - 1;
2095 			} else {
2096 				softc->blk_mask = ~0;
2097 				softc->blk_shift = 0;
2098 			}
2099 		} else {
2100 			/*
2101 			 * The SCSI-3 spec allows 0 to mean "unspecified".
2102 			 * The SCSI-1 spec allows 0 to mean 'infinite'.
2103 			 *
2104 			 * Either works here.
2105 			 */
2106 			if (softc->max_blk == 0) {
2107 				softc->max_blk = ~0;
2108 			}
2109 			softc->blk_shift = 0;
2110 			if (softc->blk_gran != 0) {
2111 				softc->blk_mask = softc->blk_gran - 1;
2112 			} else {
2113 				softc->blk_mask = 0;
2114 			}
2115 		}
2116 
2117 		if (write_protect)
2118 			softc->flags |= SA_FLAG_TAPE_WP;
2119 
2120 		if (comp_supported) {
2121 			if (softc->saved_comp_algorithm == 0)
2122 				softc->saved_comp_algorithm =
2123 				    softc->comp_algorithm;
2124 			softc->flags |= SA_FLAG_COMP_SUPP;
2125 			if (comp_enabled)
2126 				softc->flags |= SA_FLAG_COMP_ENABLED;
2127 		} else
2128 			softc->flags |= SA_FLAG_COMP_UNSUPP;
2129 
2130 		if ((softc->buffer_mode == SMH_SA_BUF_MODE_NOBUF) &&
2131 		    (softc->quirks & SA_QUIRK_NO_MODESEL) == 0) {
2132 			error = sasetparams(periph, SA_PARAM_BUFF_MODE, 0,
2133 			    0, 0, SF_NO_PRINT);
2134 			if (error == 0)
2135 				softc->buffer_mode = SMH_SA_BUF_MODE_SIBUF;
2136 			xpt_print_path(ccb->ccb_h.path);
2137 			printf("unable to set buffered mode\n");
2138 			error = 0;	/* not an error */
2139 		}
2140 
2141 
2142 		if (error == 0) {
2143 			softc->flags |= SA_FLAG_TAPE_MOUNTED;
2144 		}
2145 exit:
2146 		if (rblim != NULL)
2147 			free(rblim, M_TEMP);
2148 
2149 		if (error != 0) {
2150 			softc->dsreg = MTIO_DSREG_NIL;
2151 		} else {
2152 			softc->fileno = softc->blkno = 0;
2153 			softc->dsreg = MTIO_DSREG_REST;
2154 		}
2155 #ifdef	SA_1FM_AT_EOD
2156 		if ((softc->quirks & SA_QUIRK_2FM) == 0)
2157 			softc->quirks |= SA_QUIRK_1FM;
2158 #else
2159 		if ((softc->quirks & SA_QUIRK_1FM) == 0)
2160 			softc->quirks |= SA_QUIRK_2FM;
2161 #endif
2162 	} else
2163 		xpt_release_ccb(ccb);
2164 
2165 	/*
2166 	 * If we return an error, we're not mounted any more,
2167 	 * so release any device reservation.
2168 	 */
2169 	if (error != 0) {
2170 		(void) sareservereleaseunit(periph, FALSE);
2171 	}
2172 	return (error);
2173 }
2174 
2175 static int
2176 sacheckeod(struct cam_periph *periph)
2177 {
2178 	int	error;
2179 	int	markswanted;
2180 	struct	sa_softc *softc;
2181 
2182 	softc = (struct sa_softc *)periph->softc;
2183 	markswanted = 0;
2184 
2185 	if ((softc->flags & SA_FLAG_TAPE_WRITTEN) != 0) {
2186 		markswanted++;
2187 		if (softc->quirks & SA_QUIRK_2FM)
2188 			markswanted++;
2189 	}
2190 
2191 	if (softc->filemarks < markswanted) {
2192 		markswanted -= softc->filemarks;
2193 		error = sawritefilemarks(periph, markswanted, FALSE);
2194 	} else {
2195 		error = 0;
2196 	}
2197 	return (error);
2198 }
2199 
2200 static int
2201 saerror(union ccb *ccb, u_int32_t cflgs, u_int32_t sflgs)
2202 {
2203 	static const char *toobig =
2204 	    "%d-byte tape record bigger than suplied buffer\n";
2205 	struct	cam_periph *periph;
2206 	struct	sa_softc *softc;
2207 	struct	ccb_scsiio *csio;
2208 	struct	scsi_sense_data *sense;
2209 	u_int32_t resid = 0;
2210 	int32_t	info = 0;
2211 	int	error_code, sense_key, asc, ascq;
2212 	int	error, defer_action;
2213 
2214 	periph = xpt_path_periph(ccb->ccb_h.path);
2215 	softc = (struct sa_softc *)periph->softc;
2216 	csio = &ccb->csio;
2217 	sense = &csio->sense_data;
2218 	scsi_extract_sense(sense, &error_code, &sense_key, &asc, &ascq);
2219 	error = 0;
2220 
2221 	/*
2222 	 * Calculate/latch up, any residuals...
2223 	 */
2224 	if ((csio->ccb_h.status & CAM_STATUS_MASK) == CAM_SCSI_STATUS_ERROR) {
2225 		if ((sense->error_code & SSD_ERRCODE_VALID) != 0) {
2226 			info = (int32_t) scsi_4btoul(sense->info);
2227 			resid = info;
2228 			if ((softc->flags & SA_FLAG_FIXED) != 0)
2229 				resid *= softc->media_blksize;
2230 		} else {
2231 			resid = csio->dxfer_len;
2232 			info = resid;
2233 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
2234 				if (softc->media_blksize)
2235 					info /= softc->media_blksize;
2236 			}
2237 		}
2238 		if (csio->ccb_h.ccb_type == SA_CCB_BUFFER_IO) {
2239 			bcopy((caddr_t) sense, (caddr_t) &softc->last_io_sense,
2240 			    sizeof (struct scsi_sense_data));
2241 			bcopy(csio->cdb_io.cdb_bytes, softc->last_io_cdb,
2242 			    (int) csio->cdb_len);
2243 			softc->last_io_resid = resid;
2244 		} else {
2245 			bcopy((caddr_t) sense, (caddr_t) &softc->last_ctl_sense,
2246 			    sizeof (struct scsi_sense_data));
2247 			bcopy(csio->cdb_io.cdb_bytes, softc->last_ctl_cdb,
2248 			    (int) csio->cdb_len);
2249 			softc->last_ctl_resid = resid;
2250 		}
2251 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO, ("Key 0x%x ASC/ASCQ
2252 		    0x%x 0x%x flags 0x%x resid %d dxfer_len %d\n", sense_key,
2253 		    asc, ascq, sense->flags & ~SSD_KEY_RESERVED, resid,
2254 		    csio->dxfer_len));
2255 	} else {
2256 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO, ("Cam Status 0x%x\n",
2257 		    csio->ccb_h.status & CAM_STATUS_MASK));
2258 	}
2259 
2260 	/*
2261 	 * If it's neither a SCSI Check Condition Error nor a non-read/write
2262 	 * command, let the common code deal with it the error setting.
2263 	 */
2264 	if ((csio->ccb_h.status & CAM_STATUS_MASK) != CAM_SCSI_STATUS_ERROR ||
2265 	    (csio->ccb_h.ccb_type == SA_CCB_WAITING)) {
2266 		return (cam_periph_error(ccb, cflgs, sflgs, &softc->saved_ccb));
2267 	}
2268 
2269 	/*
2270 	 * Calculate whether we'll defer action.
2271 	 */
2272 
2273 	if (resid > 0 && resid < csio->dxfer_len &&
2274 	    (softc->flags & SA_FLAG_FIXED) != 0) {
2275 		defer_action = TRUE;
2276 	} else {
2277 		defer_action = FALSE;
2278 	}
2279 
2280 	/*
2281 	 * Handle filemark, end of tape, mismatched record sizes....
2282 	 * From this point out, we're only handling read/write cases.
2283 	 * Handle writes && reads differently.
2284 	 */
2285 
2286 	if (csio->cdb_io.cdb_bytes[0] == SA_WRITE) {
2287 		if (sense->flags & SSD_FILEMARK) {
2288 			xpt_print_path(csio->ccb_h.path);
2289 			printf("filemark detected on write?\n");
2290 			if (softc->fileno != (daddr_t) -1) {
2291 				softc->fileno++;
2292 				softc->blkno = 0;
2293 			}
2294 		}
2295 		if (sense->flags & SSD_EOM) {
2296 			csio->resid = resid;
2297 			if (defer_action) {
2298 				error = -1;
2299 				softc->flags |= SA_FLAG_EOM_PENDING;
2300 			} else {
2301 				error = ENOSPC;
2302 			}
2303 		}
2304 	} else {
2305 		if (sense_key == SSD_KEY_BLANK_CHECK) {
2306 			csio->resid = resid;
2307 			if (defer_action) {
2308 				error = -1;
2309 				softc->flags |= SA_FLAG_EOM_PENDING;
2310 			} else {
2311 				error = EIO;
2312 			}
2313 		}
2314 		if (sense->flags & SSD_FILEMARK) {
2315 			csio->resid = resid;
2316 			if (defer_action) {
2317 				error = -1;
2318 				softc->flags |= SA_FLAG_EOF_PENDING;
2319 			}
2320 			/*
2321 			 * Unconditionally, if we detected a filemark on a read,
2322 			 * mark that we've run moved a file ahead.
2323 			 */
2324 			if (softc->fileno != (daddr_t) -1) {
2325 				softc->fileno++;
2326 				softc->blkno = 0;
2327 			}
2328 		}
2329 	}
2330 	/*
2331 	 * Incorrect Length usually applies to read, but can apply to writes.
2332 	 */
2333 	if (error == 0 && (sense->flags & SSD_ILI)) {
2334 		if (info < 0) {
2335 			xpt_print_path(csio->ccb_h.path);
2336 			printf(toobig, csio->dxfer_len - info);
2337 			csio->resid = csio->dxfer_len;
2338 			error = EIO;
2339 		} else {
2340 			csio->resid = resid;
2341 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
2342 				if (defer_action)
2343 					softc->flags |= SA_FLAG_EIO_PENDING;
2344 				else
2345 					error = EIO;
2346 			}
2347 			/*
2348 			 * Bump the block number if we hadn't seen a filemark.
2349 			 * Do this independent of errors (we've moved anyway).
2350 			 */
2351 			if ((sense->flags & SSD_FILEMARK) == 0) {
2352 				if (softc->blkno != (daddr_t) -1) {
2353 					softc->blkno++;
2354 				}
2355 			}
2356 		}
2357 	}
2358 	if (error == 0)
2359 		return (cam_periph_error(ccb, cflgs, sflgs, &softc->saved_ccb));
2360 
2361 	if (error == -1)
2362 		return (0);
2363 	else
2364 		return (error);
2365 }
2366 
2367 static int
2368 sagetparams(struct cam_periph *periph, sa_params params_to_get,
2369 	    u_int32_t *blocksize, u_int8_t *density, u_int32_t *numblocks,
2370 	    int *buff_mode, u_int8_t *write_protect, u_int8_t *speed,
2371 	    int *comp_supported, int *comp_enabled, u_int32_t *comp_algorithm,
2372 	    sa_comp_t *tcs)
2373 {
2374 	union ccb *ccb;
2375 	void *mode_buffer;
2376 	struct scsi_mode_header_6 *mode_hdr;
2377 	struct scsi_mode_blk_desc *mode_blk;
2378 	int mode_buffer_len;
2379 	struct sa_softc *softc;
2380 	u_int8_t cpage;
2381 	int error;
2382 	cam_status status;
2383 
2384 	softc = (struct sa_softc *)periph->softc;
2385 	ccb = cam_periph_getccb(periph, 1);
2386 	cpage = SA_DATA_COMPRESSION_PAGE;
2387 
2388 retry:
2389 	mode_buffer_len = sizeof(*mode_hdr) + sizeof(*mode_blk);
2390 
2391 	if (params_to_get & SA_PARAM_COMPRESSION) {
2392 		if (softc->quirks & SA_QUIRK_NOCOMP) {
2393 			*comp_supported = FALSE;
2394 			params_to_get &= ~SA_PARAM_COMPRESSION;
2395 		} else
2396 			mode_buffer_len += sizeof (sa_comp_t);
2397 	}
2398 
2399 	mode_buffer = malloc(mode_buffer_len, M_TEMP, M_WAITOK);
2400 	bzero(mode_buffer, mode_buffer_len);
2401 	mode_hdr = (struct scsi_mode_header_6 *)mode_buffer;
2402 	mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
2403 
2404 	/* it is safe to retry this */
2405 	scsi_mode_sense(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2406 	    SMS_PAGE_CTRL_CURRENT, (params_to_get & SA_PARAM_COMPRESSION) ?
2407 	    cpage : SMS_VENDOR_SPECIFIC_PAGE, mode_buffer, mode_buffer_len,
2408 	    SSD_FULL_SIZE, 5000);
2409 
2410 	error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2411 	    &softc->device_stats);
2412 	QFRLS(ccb);
2413 
2414 	status = ccb->ccb_h.status & CAM_STATUS_MASK;
2415 
2416 	if (error == EINVAL && (params_to_get & SA_PARAM_COMPRESSION) != 0) {
2417 		/*
2418 		 * Hmm. Let's see if we can try another page...
2419 		 * If we've already done that, give up on compression
2420 		 * for this device and remember this for the future
2421 		 * and attempt the request without asking for compression
2422 		 * info.
2423 		 */
2424 		if (cpage == SA_DATA_COMPRESSION_PAGE) {
2425 			cpage = SA_DEVICE_CONFIGURATION_PAGE;
2426 			goto retry;
2427 		}
2428 		softc->quirks |= SA_QUIRK_NOCOMP;
2429 		free(mode_buffer, M_TEMP);
2430 		goto retry;
2431 	} else if (status == CAM_SCSI_STATUS_ERROR) {
2432 		/* Tell the user about the fatal error. */
2433 		scsi_sense_print(&ccb->csio);
2434 		goto sagetparamsexit;
2435 	}
2436 
2437 	/*
2438 	 * If the user only wants the compression information, and
2439 	 * the device doesn't send back the block descriptor, it's
2440 	 * no big deal.  If the user wants more than just
2441 	 * compression, though, and the device doesn't pass back the
2442 	 * block descriptor, we need to send another mode sense to
2443 	 * get the block descriptor.
2444 	 */
2445 	if ((mode_hdr->blk_desc_len == 0) &&
2446 	    (params_to_get & SA_PARAM_COMPRESSION) &&
2447 	    (params_to_get & ~(SA_PARAM_COMPRESSION))) {
2448 
2449 		/*
2450 		 * Decrease the mode buffer length by the size of
2451 		 * the compression page, to make sure the data
2452 		 * there doesn't get overwritten.
2453 		 */
2454 		mode_buffer_len -= sizeof (sa_comp_t);
2455 
2456 		/*
2457 		 * Now move the compression page that we presumably
2458 		 * got back down the memory chunk a little bit so
2459 		 * it doesn't get spammed.
2460 		 */
2461 		bcopy(&mode_hdr[0], &mode_hdr[1], sizeof (sa_comp_t));
2462 		bzero(&mode_hdr[0], sizeof (mode_hdr[0]));
2463 
2464 		/*
2465 		 * Now, we issue another mode sense and just ask
2466 		 * for the block descriptor, etc.
2467 		 */
2468 
2469 		scsi_mode_sense(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2470 		    SMS_PAGE_CTRL_CURRENT, SMS_VENDOR_SPECIFIC_PAGE,
2471 		    mode_buffer, mode_buffer_len, SSD_FULL_SIZE, 5000);
2472 
2473 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2474 		    &softc->device_stats);
2475 		QFRLS(ccb);
2476 
2477 		if (error != 0)
2478 			goto sagetparamsexit;
2479 	}
2480 
2481 	if (params_to_get & SA_PARAM_BLOCKSIZE)
2482 		*blocksize = scsi_3btoul(mode_blk->blklen);
2483 
2484 	if (params_to_get & SA_PARAM_NUMBLOCKS)
2485 		*numblocks = scsi_3btoul(mode_blk->nblocks);
2486 
2487 	if (params_to_get & SA_PARAM_BUFF_MODE)
2488 		*buff_mode = mode_hdr->dev_spec & SMH_SA_BUF_MODE_MASK;
2489 
2490 	if (params_to_get & SA_PARAM_DENSITY)
2491 		*density = mode_blk->density;
2492 
2493 	if (params_to_get & SA_PARAM_WP)
2494 		*write_protect = (mode_hdr->dev_spec & SMH_SA_WP)? TRUE : FALSE;
2495 
2496 	if (params_to_get & SA_PARAM_SPEED)
2497 		*speed = mode_hdr->dev_spec & SMH_SA_SPEED_MASK;
2498 
2499 	if (params_to_get & SA_PARAM_COMPRESSION) {
2500 		sa_comp_t *ntcs = (sa_comp_t *) &mode_blk[1];
2501 		if (cpage == SA_DATA_COMPRESSION_PAGE) {
2502 			struct scsi_data_compression_page *cp = &ntcs->dcomp;
2503 			*comp_supported =
2504 			    (cp->dce_and_dcc & SA_DCP_DCC)? TRUE : FALSE;
2505 			*comp_enabled =
2506 			    (cp->dce_and_dcc & SA_DCP_DCE)? TRUE : FALSE;
2507 			*comp_algorithm = scsi_4btoul(cp->comp_algorithm);
2508 		} else {
2509 			struct scsi_dev_conf_page *cp = &ntcs->dconf;
2510 			/*
2511 			 * We don't really know whether this device supports
2512 			 * Data Compression if the the algorithm field is
2513 			 * zero. Just say we do.
2514 			 */
2515 			*comp_supported = TRUE;
2516 			*comp_enabled =
2517 			    (cp->sel_comp_alg != SA_COMP_NONE)? TRUE : FALSE;
2518 			*comp_algorithm = cp->sel_comp_alg;
2519 		}
2520 		if (tcs != NULL)
2521 			bcopy(ntcs, tcs, sizeof (sa_comp_t));
2522 	}
2523 
2524 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
2525 		int idx;
2526 		char *xyz = mode_buffer;
2527 		xpt_print_path(periph->path);
2528 		printf("Mode Sense Data=");
2529 		for (idx = 0; idx < mode_buffer_len; idx++)
2530 			printf(" 0x%02x", xyz[idx] & 0xff);
2531 		printf("\n");
2532 	}
2533 
2534 sagetparamsexit:
2535 
2536 	xpt_release_ccb(ccb);
2537 	free(mode_buffer, M_TEMP);
2538 	return (error);
2539 }
2540 
2541 /*
2542  * The purpose of this function is to set one of four different parameters
2543  * for a tape drive:
2544  *	- blocksize
2545  *	- density
2546  *	- compression / compression algorithm
2547  *	- buffering mode
2548  *
2549  * The assumption is that this will be called from saioctl(), and therefore
2550  * from a process context.  Thus the waiting malloc calls below.  If that
2551  * assumption ever changes, the malloc calls should be changed to be
2552  * NOWAIT mallocs.
2553  *
2554  * Any or all of the four parameters may be set when this function is
2555  * called.  It should handle setting more than one parameter at once.
2556  */
2557 static int
2558 sasetparams(struct cam_periph *periph, sa_params params_to_set,
2559 	    u_int32_t blocksize, u_int8_t density, u_int32_t calg,
2560 	    u_int32_t sense_flags)
2561 {
2562 	struct sa_softc *softc;
2563 	u_int32_t current_blocksize;
2564 	u_int32_t current_calg;
2565 	u_int8_t current_density;
2566 	u_int8_t current_speed;
2567 	int comp_enabled, comp_supported;
2568 	void *mode_buffer;
2569 	int mode_buffer_len;
2570 	struct scsi_mode_header_6 *mode_hdr;
2571 	struct scsi_mode_blk_desc *mode_blk;
2572 	sa_comp_t *ccomp, *cpage;
2573 	int buff_mode;
2574 	union ccb *ccb = NULL;
2575 	int error;
2576 
2577 	softc = (struct sa_softc *)periph->softc;
2578 
2579 	ccomp = malloc(sizeof (sa_comp_t), M_TEMP, M_WAITOK);
2580 
2581 	/*
2582 	 * Since it doesn't make sense to set the number of blocks, or
2583 	 * write protection, we won't try to get the current value.  We
2584 	 * always want to get the blocksize, so we can set it back to the
2585 	 * proper value.
2586 	 */
2587 	error = sagetparams(periph,
2588 	    params_to_set | SA_PARAM_BLOCKSIZE | SA_PARAM_SPEED,
2589 	    &current_blocksize, &current_density, NULL, &buff_mode, NULL,
2590 	    &current_speed, &comp_supported, &comp_enabled,
2591 	    &current_calg, ccomp);
2592 
2593 	if (error != 0) {
2594 		free(ccomp, M_TEMP);
2595 		return (error);
2596 	}
2597 
2598 	mode_buffer_len = sizeof(*mode_hdr) + sizeof(*mode_blk);
2599 	if (params_to_set & SA_PARAM_COMPRESSION)
2600 		mode_buffer_len += sizeof (sa_comp_t);
2601 
2602 	mode_buffer = malloc(mode_buffer_len, M_TEMP, M_WAITOK);
2603 	bzero(mode_buffer, mode_buffer_len);
2604 
2605 	mode_hdr = (struct scsi_mode_header_6 *)mode_buffer;
2606 	mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
2607 
2608 	ccb = cam_periph_getccb(periph, 1);
2609 
2610 retry:
2611 
2612 	if (params_to_set & SA_PARAM_COMPRESSION) {
2613 		if (mode_blk) {
2614 			cpage = (sa_comp_t *)&mode_blk[1];
2615 		} else {
2616 			cpage = (sa_comp_t *)&mode_hdr[1];
2617 		}
2618 		bcopy(ccomp, cpage, sizeof (sa_comp_t));
2619 		cpage->hdr.pagecode &= ~0x80;
2620 	} else
2621 		cpage = NULL;
2622 
2623 	/*
2624 	 * If the caller wants us to set the blocksize, use the one they
2625 	 * pass in.  Otherwise, use the blocksize we got back from the
2626 	 * mode select above.
2627 	 */
2628 	if (mode_blk) {
2629 		if (params_to_set & SA_PARAM_BLOCKSIZE)
2630 			scsi_ulto3b(blocksize, mode_blk->blklen);
2631 		else
2632 			scsi_ulto3b(current_blocksize, mode_blk->blklen);
2633 
2634 		/*
2635 		 * Set density if requested, else preserve old density.
2636 		 * SCSI_SAME_DENSITY only applies to SCSI-2 or better
2637 		 * devices, else density we've latched up in our softc.
2638 		 */
2639 		if (params_to_set & SA_PARAM_DENSITY) {
2640 			mode_blk->density = density;
2641 		} else if (softc->scsi_rev > SCSI_REV_CCS) {
2642 			mode_blk->density = SCSI_SAME_DENSITY;
2643 		} else {
2644 			mode_blk->density = softc->media_density;
2645 		}
2646 	}
2647 
2648 	/*
2649 	 * For mode selects, these two fields must be zero.
2650 	 */
2651 	mode_hdr->data_length = 0;
2652 	mode_hdr->medium_type = 0;
2653 
2654 	/* set the speed to the current value */
2655 	mode_hdr->dev_spec = current_speed;
2656 
2657 	/* set single-initiator buffering mode */
2658 	mode_hdr->dev_spec |= SMH_SA_BUF_MODE_SIBUF;
2659 
2660 	if (mode_blk)
2661 		mode_hdr->blk_desc_len = sizeof(struct scsi_mode_blk_desc);
2662 	else
2663 		mode_hdr->blk_desc_len = 0;
2664 
2665 	/*
2666 	 * First, if the user wants us to set the compression algorithm or
2667 	 * just turn compression on, check to make sure that this drive
2668 	 * supports compression.
2669 	 */
2670 	if (params_to_set & SA_PARAM_COMPRESSION) {
2671 		/*
2672 		 * If the compression algorithm is 0, disable compression.
2673 		 * If the compression algorithm is non-zero, enable
2674 		 * compression and set the compression type to the
2675 		 * specified compression algorithm, unless the algorithm is
2676 		 * MT_COMP_ENABLE.  In that case, we look at the
2677 		 * compression algorithm that is currently set and if it is
2678 		 * non-zero, we leave it as-is.  If it is zero, and we have
2679 		 * saved a compression algorithm from a time when
2680 		 * compression was enabled before, set the compression to
2681 		 * the saved value.
2682 		 */
2683 		switch (ccomp->hdr.pagecode & ~0x80) {
2684 		case SA_DATA_COMPRESSION_PAGE:
2685 		if (ccomp->dcomp.dce_and_dcc & SA_DCP_DCC) {
2686 			struct scsi_data_compression_page *dcp = &cpage->dcomp;
2687 			if (calg == 0) {
2688 				/*
2689 				 * Disable compression, but leave the
2690 				 * decompression and the capability bit
2691 				 * alone.
2692 				 */
2693 				dcp->dce_and_dcc = SA_DCP_DCC;
2694 				dcp->dde_and_red |= SA_DCP_DDE;
2695 				break;
2696 			}
2697 			/* enable compression && decompression */
2698 			dcp->dce_and_dcc = SA_DCP_DCE | SA_DCP_DCC;
2699 			dcp->dde_and_red |= SA_DCP_DDE;
2700 			/*
2701 			 * If there, use compression algorithm from caller.
2702 			 * Otherwise, if there's a saved compression algorithm
2703 			 * and there is no current algorithm, use the saved
2704 			 * algorithm. Else parrot back what we got and hope
2705 			 * for the best.
2706 			 */
2707 			if (calg != MT_COMP_ENABLE) {
2708 				scsi_ulto4b(calg, dcp->comp_algorithm);
2709 				scsi_ulto4b(calg, dcp->decomp_algorithm);
2710 			} else if (scsi_4btoul(dcp->comp_algorithm) == 0 &&
2711 			    softc->saved_comp_algorithm != 0) {
2712 				scsi_ulto4b(softc->saved_comp_algorithm,
2713 				    dcp->comp_algorithm);
2714 				scsi_ulto4b(softc->saved_comp_algorithm,
2715 				    dcp->decomp_algorithm);
2716 			}
2717 			break;
2718 		}
2719 		case SA_DEVICE_CONFIGURATION_PAGE:
2720 		{
2721 			struct scsi_dev_conf_page *dcp = &cpage->dconf;
2722 			if (calg == 0) {
2723 				dcp->sel_comp_alg = SA_COMP_NONE;
2724 				break;
2725 			}
2726 			if (calg != MT_COMP_ENABLE) {
2727 				dcp->sel_comp_alg = calg;
2728 			} else if (dcp->sel_comp_alg == SA_COMP_NONE &&
2729 			    softc->saved_comp_algorithm != 0) {
2730 				dcp->sel_comp_alg = softc->saved_comp_algorithm;
2731 			}
2732 			break;
2733 		}
2734 		default:
2735 			/*
2736 			 * The drive doesn't seem to support compression,
2737 			 * so turn off the set compression bit.
2738 			 */
2739 			params_to_set &= ~SA_PARAM_COMPRESSION;
2740 			xpt_print_path(periph->path);
2741 			printf("device does not seem to support compression\n");
2742 
2743 			/*
2744 			 * If that was the only thing the user wanted us to set,
2745 			 * clean up allocated resources and return with
2746 			 * 'operation not supported'.
2747 			 */
2748 			if (params_to_set == SA_PARAM_NONE) {
2749 				free(mode_buffer, M_TEMP);
2750 				xpt_release_ccb(ccb);
2751 				return (ENODEV);
2752 			}
2753 
2754 			/*
2755 			 * That wasn't the only thing the user wanted us to set.
2756 			 * So, decrease the stated mode buffer length by the
2757 			 * size of the compression mode page.
2758 			 */
2759 			mode_buffer_len -= sizeof(sa_comp_t);
2760 		}
2761 	}
2762 
2763 	/* It is safe to retry this operation */
2764 	scsi_mode_select(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG,
2765 	    (params_to_set & SA_PARAM_COMPRESSION)? TRUE : FALSE,
2766 	    FALSE, mode_buffer, mode_buffer_len, SSD_FULL_SIZE, 5000);
2767 
2768 	error = cam_periph_runccb(ccb, saerror, 0,
2769 	    sense_flags, &softc->device_stats);
2770 	QFRLS(ccb);
2771 
2772 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
2773 		int idx;
2774 		char *xyz = mode_buffer;
2775 		xpt_print_path(periph->path);
2776 		printf("Err%d, Mode Select Data=", error);
2777 		for (idx = 0; idx < mode_buffer_len; idx++)
2778 			printf(" 0x%02x", xyz[idx] & 0xff);
2779 		printf("\n");
2780 	}
2781 
2782 
2783 	if (error) {
2784 		/*
2785 		 * If we can, try without setting density/blocksize.
2786 		 */
2787 		if (mode_blk) {
2788 			if ((params_to_set &
2789 			    (SA_PARAM_DENSITY|SA_PARAM_BLOCKSIZE)) == 0) {
2790 				mode_blk = NULL;
2791 				goto retry;
2792 			}
2793 		} else {
2794 			mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
2795 			cpage = (sa_comp_t *)&mode_blk[1];
2796 		}
2797 
2798 		/*
2799 		 * If we were setting the blocksize, and that failed, we
2800 		 * want to set it to its original value.  If we weren't
2801 		 * setting the blocksize, we don't want to change it.
2802 		 */
2803 		scsi_ulto3b(current_blocksize, mode_blk->blklen);
2804 
2805 		/*
2806 		 * Set density if requested, else preserve old density.
2807 		 * SCSI_SAME_DENSITY only applies to SCSI-2 or better
2808 		 * devices, else density we've latched up in our softc.
2809 		 */
2810 		if (params_to_set & SA_PARAM_DENSITY) {
2811 			mode_blk->density = current_density;
2812 		} else if (softc->scsi_rev > SCSI_REV_CCS) {
2813 			mode_blk->density = SCSI_SAME_DENSITY;
2814 		} else {
2815 			mode_blk->density = softc->media_density;
2816 		}
2817 
2818 		if (params_to_set & SA_PARAM_COMPRESSION)
2819 			bcopy(ccomp, cpage, sizeof (sa_comp_t));
2820 
2821 		/*
2822 		 * The retry count is the only CCB field that might have been
2823 		 * changed that we care about, so reset it back to 1.
2824 		 */
2825 		ccb->ccb_h.retry_count = 1;
2826 		cam_periph_runccb(ccb, saerror, 0, sense_flags,
2827 		    &softc->device_stats);
2828 		QFRLS(ccb);
2829 	}
2830 
2831 	xpt_release_ccb(ccb);
2832 
2833 	if (ccomp != NULL)
2834 		free(ccomp, M_TEMP);
2835 
2836 	if (params_to_set & SA_PARAM_COMPRESSION) {
2837 		if (error) {
2838 			softc->flags &= ~SA_FLAG_COMP_ENABLED;
2839 			/*
2840 			 * Even if we get an error setting compression,
2841 			 * do not say that we don't support it. We could
2842 			 * have been wrong, or it may be media specific.
2843 			 *	softc->flags &= ~SA_FLAG_COMP_SUPP;
2844 			 */
2845 			softc->saved_comp_algorithm = softc->comp_algorithm;
2846 			softc->comp_algorithm = 0;
2847 		} else {
2848 			softc->flags |= SA_FLAG_COMP_ENABLED;
2849 			softc->comp_algorithm = calg;
2850 		}
2851 	}
2852 
2853 	free(mode_buffer, M_TEMP);
2854 	return (error);
2855 }
2856 
2857 static void
2858 saprevent(struct cam_periph *periph, int action)
2859 {
2860 	struct	sa_softc *softc;
2861 	union	ccb *ccb;
2862 	int	error, sf;
2863 
2864 	softc = (struct sa_softc *)periph->softc;
2865 
2866 	if ((action == PR_ALLOW) && (softc->flags & SA_FLAG_TAPE_LOCKED) == 0)
2867 		return;
2868 	if ((action == PR_PREVENT) && (softc->flags & SA_FLAG_TAPE_LOCKED) != 0)
2869 		return;
2870 
2871 	/*
2872 	 * We can be quiet about illegal requests.
2873 	 */
2874 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
2875 		sf = 0;
2876 	} else
2877 		sf = SF_QUIET_IR;
2878 
2879 	ccb = cam_periph_getccb(periph, 1);
2880 
2881 	/* It is safe to retry this operation */
2882 	scsi_prevent(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, action,
2883 	    SSD_FULL_SIZE, 100000);
2884 
2885 	error = cam_periph_runccb(ccb, saerror, 0, sf, &softc->device_stats);
2886 	QFRLS(ccb);
2887 	if (error == 0) {
2888 		if (action == PR_ALLOW)
2889 			softc->flags &= ~SA_FLAG_TAPE_LOCKED;
2890 		else
2891 			softc->flags |= SA_FLAG_TAPE_LOCKED;
2892 	}
2893 
2894 	xpt_release_ccb(ccb);
2895 }
2896 
2897 static int
2898 sarewind(struct cam_periph *periph)
2899 {
2900 	union	ccb *ccb;
2901 	struct	sa_softc *softc;
2902 	int	error;
2903 
2904 	softc = (struct sa_softc *)periph->softc;
2905 
2906 	ccb = cam_periph_getccb(periph, 1);
2907 
2908 	/* It is safe to retry this operation */
2909 	scsi_rewind(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2910 	    SSD_FULL_SIZE, REWIND_TIMEOUT);
2911 
2912 	softc->dsreg = MTIO_DSREG_REW;
2913 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
2914 	softc->dsreg = MTIO_DSREG_REST;
2915 
2916 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
2917 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, FALSE);
2918 
2919 	xpt_release_ccb(ccb);
2920 	if (error == 0)
2921 		softc->fileno = softc->blkno = (daddr_t) 0;
2922 	else
2923 		softc->fileno = softc->blkno = (daddr_t) -1;
2924 	return (error);
2925 }
2926 
2927 static int
2928 saspace(struct cam_periph *periph, int count, scsi_space_code code)
2929 {
2930 	union	ccb *ccb;
2931 	struct	sa_softc *softc;
2932 	int	error;
2933 
2934 	softc = (struct sa_softc *)periph->softc;
2935 
2936 	ccb = cam_periph_getccb(periph, 1);
2937 
2938 	/* This cannot be retried */
2939 
2940 	scsi_space(&ccb->csio, 0, sadone, MSG_SIMPLE_Q_TAG, code, count,
2941 	    SSD_FULL_SIZE, SPACE_TIMEOUT);
2942 
2943 	softc->dsreg = (count < 0)? MTIO_DSREG_REV : MTIO_DSREG_FWD;
2944 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
2945 	softc->dsreg = MTIO_DSREG_REST;
2946 
2947 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
2948 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, FALSE);
2949 
2950 	xpt_release_ccb(ccb);
2951 
2952 	/*
2953 	 * If a spacing operation has failed, we need to invalidate
2954 	 * this mount.
2955 	 *
2956 	 * If the spacing operation was setmarks or to end of recorded data,
2957 	 * we no longer know our relative position.
2958 	 *
2959 	 * We are not managing residuals here (really).
2960 	 */
2961 	if (error) {
2962 		softc->fileno = softc->blkno = (daddr_t) -1;
2963 	} else if (code == SS_SETMARKS || code == SS_EOD) {
2964 		softc->fileno = softc->blkno = (daddr_t) -1;
2965 	} else if (code == SS_FILEMARKS && softc->fileno != (daddr_t) -1) {
2966 		softc->fileno += count;
2967 		softc->blkno = 0;
2968 	} else if (code == SS_BLOCKS && softc->blkno != (daddr_t) -1) {
2969 		softc->blkno += count;
2970 	}
2971 	return (error);
2972 }
2973 
2974 static int
2975 sawritefilemarks(struct cam_periph *periph, int nmarks, int setmarks)
2976 {
2977 	union	ccb *ccb;
2978 	struct	sa_softc *softc;
2979 	int	error;
2980 
2981 	softc = (struct sa_softc *)periph->softc;
2982 
2983 	ccb = cam_periph_getccb(periph, 1);
2984 
2985 	softc->dsreg = MTIO_DSREG_FMK;
2986 	/* this *must* not be retried */
2987 	scsi_write_filemarks(&ccb->csio, 0, sadone, MSG_SIMPLE_Q_TAG,
2988 	    FALSE, setmarks, nmarks, SSD_FULL_SIZE, 60000);
2989 	softc->dsreg = MTIO_DSREG_REST;
2990 
2991 
2992 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
2993 
2994 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
2995 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, FALSE);
2996 
2997 	/*
2998 	 * XXXX: Get back the actual number of filemarks written
2999 	 * XXXX: (there can be a residual).
3000 	 */
3001 	if (error == 0 && nmarks) {
3002 		struct sa_softc *softc = (struct sa_softc *)periph->softc;
3003 		softc->filemarks += nmarks;
3004 	}
3005 	xpt_release_ccb(ccb);
3006 
3007 	/*
3008 	 * Update relative positions (if we're doing that).
3009 	 */
3010 	if (error) {
3011 		softc->fileno = softc->blkno = (daddr_t) -1;
3012 	} else if (softc->fileno != (daddr_t) -1) {
3013 		softc->fileno += nmarks;
3014 		softc->blkno = 0;
3015 	}
3016 	return (error);
3017 }
3018 
3019 static int
3020 sardpos(struct cam_periph *periph, int hard, u_int32_t *blkptr)
3021 {
3022 	struct scsi_tape_position_data loc;
3023 	union ccb *ccb;
3024 	struct sa_softc *softc = (struct sa_softc *)periph->softc;
3025 	int error;
3026 
3027 	/*
3028 	 * We have to try and flush any buffered writes here if we were writing.
3029 	 *
3030 	 * The SCSI specification is vague enough about situations like
3031 	 * different sized blocks in a tape drive buffer as to make one
3032 	 * wary about trying to figure out the actual block location value
3033 	 * if data is in the tape drive buffer.
3034 	 */
3035 	ccb = cam_periph_getccb(periph, 1);
3036 
3037 	if (softc->flags & SA_FLAG_TAPE_WRITTEN) {
3038 		error = sawritefilemarks(periph, 0, 0);
3039 		if (error && error != EACCES)
3040 			return (error);
3041 	}
3042 
3043 	scsi_read_position(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
3044 	    hard, &loc, SSD_FULL_SIZE, 5000);
3045 	softc->dsreg = MTIO_DSREG_RBSY;
3046 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
3047 	softc->dsreg = MTIO_DSREG_REST;
3048 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
3049 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, 0);
3050 
3051 	if (error == 0) {
3052 		if (loc.flags & SA_RPOS_UNCERTAIN) {
3053 			error = EINVAL;		/* nothing is certain */
3054 		} else {
3055 #if	0
3056 			u_int32_t firstblk, lastblk, nbufblk, nbufbyte;
3057 
3058 			firstblk = scsi_4btoul(loc.firstblk);
3059 			lastblk = scsi_4btoul(loc.lastblk);
3060 			nbufblk = scsi_4btoul(loc.nbufblk);
3061 			nbufbyte = scsi_4btoul(loc.nbufbyte);
3062 			if (lastblk || nbufblk || nbufbyte) {
3063 				xpt_print_path(periph->path);
3064 				printf("rdpos firstblk 0x%x lastblk 0x%x bufblk"
3065 				    " 0x%x bufbyte 0x%x\n", firstblk, lastblk,
3066 				    nbufblk, nbufbyte);
3067 			}
3068 			*blkptr = firstblk;
3069 #else
3070 			*blkptr = scsi_4btoul(loc.firstblk);
3071 #endif
3072 		}
3073 	}
3074 
3075 	xpt_release_ccb(ccb);
3076 	return (error);
3077 }
3078 
3079 static int
3080 sasetpos(struct cam_periph *periph, int hard, u_int32_t *blkptr)
3081 {
3082 	union ccb *ccb;
3083 	struct sa_softc *softc;
3084 	int error;
3085 
3086 	/*
3087 	 * We used to try and flush any buffered writes here.
3088 	 * Now we push this onto user applications to either
3089 	 * flush the pending writes themselves (via a zero count
3090 	 * WRITE FILEMARKS command) or they can trust their tape
3091 	 * drive to do this correctly for them.
3092  	 */
3093 
3094 	softc = (struct sa_softc *)periph->softc;
3095 	ccb = cam_periph_getccb(periph, 1);
3096 
3097 
3098 	scsi_set_position(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
3099 	    hard, *blkptr, SSD_FULL_SIZE, 60 * 60 * 1000);
3100 
3101 	softc->dsreg = MTIO_DSREG_POS;
3102 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
3103 	softc->dsreg = MTIO_DSREG_REST;
3104 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
3105 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, 0);
3106 	xpt_release_ccb(ccb);
3107 	/*
3108 	 * Note relative file && block number position as now unknown.
3109 	 */
3110 	softc->fileno = softc->blkno = (daddr_t) -1;
3111 	return (error);
3112 }
3113 
3114 static int
3115 saretension(struct cam_periph *periph)
3116 {
3117 	union ccb *ccb;
3118 	struct sa_softc *softc;
3119 	int error;
3120 
3121 	softc = (struct sa_softc *)periph->softc;
3122 
3123 	ccb = cam_periph_getccb(periph, 1);
3124 
3125 	/* It is safe to retry this operation */
3126 	scsi_load_unload(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
3127 	    FALSE, TRUE,  TRUE, SSD_FULL_SIZE, ERASE_TIMEOUT);
3128 
3129 	softc->dsreg = MTIO_DSREG_TEN;
3130 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
3131 	softc->dsreg = MTIO_DSREG_REST;
3132 
3133 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
3134 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, FALSE);
3135 	xpt_release_ccb(ccb);
3136 	if (error == 0)
3137 		softc->fileno = softc->blkno = (daddr_t) 0;
3138 	else
3139 		softc->fileno = softc->blkno = (daddr_t) -1;
3140 	return (error);
3141 }
3142 
3143 static int
3144 sareservereleaseunit(struct cam_periph *periph, int reserve)
3145 {
3146 	union ccb *ccb;
3147 	struct sa_softc *softc;
3148 	int error;
3149 
3150 	softc = (struct sa_softc *)periph->softc;
3151 	ccb = cam_periph_getccb(periph,  1);
3152 
3153 	/* It is safe to retry this operation */
3154 	scsi_reserve_release_unit(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG,
3155 	    FALSE,  0, SSD_FULL_SIZE,  5000, reserve);
3156 	softc->dsreg = MTIO_DSREG_RBSY;
3157 	error = cam_periph_runccb(ccb, saerror, 0,
3158 	    SF_RETRY_UA | SF_NO_PRINT, &softc->device_stats);
3159 	softc->dsreg = MTIO_DSREG_REST;
3160 	QFRLS(ccb);
3161 	xpt_release_ccb(ccb);
3162 
3163 	/*
3164 	 * If the error was Illegal Request, then the device doesn't support
3165 	 * RESERVE/RELEASE. This is not an error.
3166 	 */
3167 	if (error == EINVAL) {
3168 		error = 0;
3169 	}
3170 
3171 	return (error);
3172 }
3173 
3174 static int
3175 saloadunload(struct cam_periph *periph, int load)
3176 {
3177 	union	ccb *ccb;
3178 	struct	sa_softc *softc;
3179 	int	error;
3180 
3181 	softc = (struct sa_softc *)periph->softc;
3182 
3183 	ccb = cam_periph_getccb(periph, 1);
3184 
3185 	/* It is safe to retry this operation */
3186 	scsi_load_unload(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
3187 	    FALSE, FALSE, load, SSD_FULL_SIZE, REWIND_TIMEOUT);
3188 
3189 	softc->dsreg = (load)? MTIO_DSREG_LD : MTIO_DSREG_UNL;
3190 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
3191 	softc->dsreg = MTIO_DSREG_REST;
3192 	QFRLS(ccb);
3193 	xpt_release_ccb(ccb);
3194 
3195 	if (error || load == 0)
3196 		softc->fileno = softc->blkno = (daddr_t) -1;
3197 	else if (error == 0)
3198 		softc->fileno = softc->blkno = (daddr_t) 0;
3199 	return (error);
3200 }
3201 
3202 static int
3203 saerase(struct cam_periph *periph, int longerase)
3204 {
3205 
3206 	union	ccb *ccb;
3207 	struct	sa_softc *softc;
3208 	int error;
3209 
3210 	softc = (struct sa_softc *)periph->softc;
3211 
3212 	ccb = cam_periph_getccb(periph, 1);
3213 
3214 	scsi_erase(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG, FALSE, longerase,
3215 	    SSD_FULL_SIZE, ERASE_TIMEOUT);
3216 
3217 	softc->dsreg = MTIO_DSREG_ZER;
3218 	error = cam_periph_runccb(ccb, saerror, 0, 0, &softc->device_stats);
3219 	softc->dsreg = MTIO_DSREG_REST;
3220 
3221 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
3222 		cam_release_devq(ccb->ccb_h.path, 0, 0, 0, FALSE);
3223 	xpt_release_ccb(ccb);
3224 	return (error);
3225 }
3226 
3227 #endif /* _KERNEL */
3228 
3229 /*
3230  * Read tape block limits command.
3231  */
3232 void
3233 scsi_read_block_limits(struct ccb_scsiio *csio, u_int32_t retries,
3234 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3235 		   u_int8_t tag_action,
3236 		   struct scsi_read_block_limits_data *rlimit_buf,
3237 		   u_int8_t sense_len, u_int32_t timeout)
3238 {
3239 	struct scsi_read_block_limits *scsi_cmd;
3240 
3241 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_IN, tag_action,
3242 	     (u_int8_t *)rlimit_buf, sizeof(*rlimit_buf), sense_len,
3243 	     sizeof(*scsi_cmd), timeout);
3244 
3245 	scsi_cmd = (struct scsi_read_block_limits *)&csio->cdb_io.cdb_bytes;
3246 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3247 	scsi_cmd->opcode = READ_BLOCK_LIMITS;
3248 }
3249 
3250 void
3251 scsi_sa_read_write(struct ccb_scsiio *csio, u_int32_t retries,
3252 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3253 		   u_int8_t tag_action, int readop, int sli,
3254 		   int fixed, u_int32_t length, u_int8_t *data_ptr,
3255 		   u_int32_t dxfer_len, u_int8_t sense_len, u_int32_t timeout)
3256 {
3257 	struct scsi_sa_rw *scsi_cmd;
3258 
3259 	scsi_cmd = (struct scsi_sa_rw *)&csio->cdb_io.cdb_bytes;
3260 	scsi_cmd->opcode = readop ? SA_READ : SA_WRITE;
3261 	scsi_cmd->sli_fixed = 0;
3262 	if (sli && readop)
3263 		scsi_cmd->sli_fixed |= SAR_SLI;
3264 	if (fixed)
3265 		scsi_cmd->sli_fixed |= SARW_FIXED;
3266 	scsi_ulto3b(length, scsi_cmd->length);
3267 	scsi_cmd->control = 0;
3268 
3269 	cam_fill_csio(csio, retries, cbfcnp, readop ? CAM_DIR_IN : CAM_DIR_OUT,
3270 	    tag_action, data_ptr, dxfer_len, sense_len,
3271 	    sizeof(*scsi_cmd), timeout);
3272 }
3273 
3274 void
3275 scsi_load_unload(struct ccb_scsiio *csio, u_int32_t retries,
3276 		 void (*cbfcnp)(struct cam_periph *, union ccb *),
3277 		 u_int8_t tag_action, int immediate, int eot,
3278 		 int reten, int load, u_int8_t sense_len,
3279 		 u_int32_t timeout)
3280 {
3281 	struct scsi_load_unload *scsi_cmd;
3282 
3283 	scsi_cmd = (struct scsi_load_unload *)&csio->cdb_io.cdb_bytes;
3284 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3285 	scsi_cmd->opcode = LOAD_UNLOAD;
3286 	if (immediate)
3287 		scsi_cmd->immediate = SLU_IMMED;
3288 	if (eot)
3289 		scsi_cmd->eot_reten_load |= SLU_EOT;
3290 	if (reten)
3291 		scsi_cmd->eot_reten_load |= SLU_RETEN;
3292 	if (load)
3293 		scsi_cmd->eot_reten_load |= SLU_LOAD;
3294 
3295 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action,
3296 	    NULL, 0, sense_len, sizeof(*scsi_cmd), timeout);
3297 }
3298 
3299 void
3300 scsi_rewind(struct ccb_scsiio *csio, u_int32_t retries,
3301 	    void (*cbfcnp)(struct cam_periph *, union ccb *),
3302 	    u_int8_t tag_action, int immediate, u_int8_t sense_len,
3303 	    u_int32_t timeout)
3304 {
3305 	struct scsi_rewind *scsi_cmd;
3306 
3307 	scsi_cmd = (struct scsi_rewind *)&csio->cdb_io.cdb_bytes;
3308 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3309 	scsi_cmd->opcode = REWIND;
3310 	if (immediate)
3311 		scsi_cmd->immediate = SREW_IMMED;
3312 
3313 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3314 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3315 }
3316 
3317 void
3318 scsi_space(struct ccb_scsiio *csio, u_int32_t retries,
3319 	   void (*cbfcnp)(struct cam_periph *, union ccb *),
3320 	   u_int8_t tag_action, scsi_space_code code,
3321 	   u_int32_t count, u_int8_t sense_len, u_int32_t timeout)
3322 {
3323 	struct scsi_space *scsi_cmd;
3324 
3325 	scsi_cmd = (struct scsi_space *)&csio->cdb_io.cdb_bytes;
3326 	scsi_cmd->opcode = SPACE;
3327 	scsi_cmd->code = code;
3328 	scsi_ulto3b(count, scsi_cmd->count);
3329 	scsi_cmd->control = 0;
3330 
3331 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3332 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3333 }
3334 
3335 void
3336 scsi_write_filemarks(struct ccb_scsiio *csio, u_int32_t retries,
3337 		     void (*cbfcnp)(struct cam_periph *, union ccb *),
3338 		     u_int8_t tag_action, int immediate, int setmark,
3339 		     u_int32_t num_marks, u_int8_t sense_len,
3340 		     u_int32_t timeout)
3341 {
3342 	struct scsi_write_filemarks *scsi_cmd;
3343 
3344 	scsi_cmd = (struct scsi_write_filemarks *)&csio->cdb_io.cdb_bytes;
3345 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3346 	scsi_cmd->opcode = WRITE_FILEMARKS;
3347 	if (immediate)
3348 		scsi_cmd->byte2 |= SWFMRK_IMMED;
3349 	if (setmark)
3350 		scsi_cmd->byte2 |= SWFMRK_WSMK;
3351 
3352 	scsi_ulto3b(num_marks, scsi_cmd->num_marks);
3353 
3354 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3355 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3356 }
3357 
3358 /*
3359  * The reserve and release unit commands differ only by their opcodes.
3360  */
3361 void
3362 scsi_reserve_release_unit(struct ccb_scsiio *csio, u_int32_t retries,
3363 			  void (*cbfcnp)(struct cam_periph *, union ccb *),
3364 			  u_int8_t tag_action, int third_party,
3365 			  int third_party_id, u_int8_t sense_len,
3366 			  u_int32_t timeout, int reserve)
3367 {
3368 	struct scsi_reserve_release_unit *scsi_cmd;
3369 
3370 	scsi_cmd = (struct scsi_reserve_release_unit *)&csio->cdb_io.cdb_bytes;
3371 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3372 
3373 	if (reserve)
3374 		scsi_cmd->opcode = RESERVE_UNIT;
3375 	else
3376 		scsi_cmd->opcode = RELEASE_UNIT;
3377 
3378 	if (third_party) {
3379 		scsi_cmd->lun_thirdparty |= SRRU_3RD_PARTY;
3380 		scsi_cmd->lun_thirdparty |=
3381 			((third_party_id << SRRU_3RD_SHAMT) & SRRU_3RD_MASK);
3382 	}
3383 
3384 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3385 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3386 }
3387 
3388 void
3389 scsi_erase(struct ccb_scsiio *csio, u_int32_t retries,
3390 	   void (*cbfcnp)(struct cam_periph *, union ccb *),
3391 	   u_int8_t tag_action, int immediate, int long_erase,
3392 	   u_int8_t sense_len, u_int32_t timeout)
3393 {
3394 	struct scsi_erase *scsi_cmd;
3395 
3396 	scsi_cmd = (struct scsi_erase *)&csio->cdb_io.cdb_bytes;
3397 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3398 
3399 	scsi_cmd->opcode = ERASE;
3400 
3401 	if (immediate)
3402 		scsi_cmd->lun_imm_long |= SE_IMMED;
3403 
3404 	if (long_erase)
3405 		scsi_cmd->lun_imm_long |= SE_LONG;
3406 
3407 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3408 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3409 }
3410 
3411 /*
3412  * Read Tape Position command.
3413  */
3414 void
3415 scsi_read_position(struct ccb_scsiio *csio, u_int32_t retries,
3416 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3417 		   u_int8_t tag_action, int hardsoft,
3418 		   struct scsi_tape_position_data *sbp,
3419 		   u_int8_t sense_len, u_int32_t timeout)
3420 {
3421 	struct scsi_tape_read_position *scmd;
3422 
3423 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_IN, tag_action,
3424 	    (u_int8_t *)sbp, sizeof (*sbp), sense_len, sizeof(*scmd), timeout);
3425 	scmd = (struct scsi_tape_read_position *)&csio->cdb_io.cdb_bytes;
3426 	bzero(scmd, sizeof(*scmd));
3427 	scmd->opcode = READ_POSITION;
3428 	scmd->byte1 = hardsoft;
3429 }
3430 
3431 /*
3432  * Set Tape Position command.
3433  */
3434 void
3435 scsi_set_position(struct ccb_scsiio *csio, u_int32_t retries,
3436 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3437 		   u_int8_t tag_action, int hardsoft, u_int32_t blkno,
3438 		   u_int8_t sense_len, u_int32_t timeout)
3439 {
3440 	struct scsi_tape_locate *scmd;
3441 
3442 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action,
3443 	    (u_int8_t *)NULL, 0, sense_len, sizeof(*scmd), timeout);
3444 	scmd = (struct scsi_tape_locate *)&csio->cdb_io.cdb_bytes;
3445 	bzero(scmd, sizeof(*scmd));
3446 	scmd->opcode = LOCATE;
3447 	if (hardsoft)
3448 		scmd->byte1 |= SA_SPOS_BT;
3449 	scsi_ulto4b(blkno, scmd->blkaddr);
3450 }
3451