xref: /freebsd/sys/cam/scsi/scsi_sa.c (revision ff0ba87247820afbdfdc1b307c803f7923d0e4d3)
1 /*-
2  * Implementation of SCSI Sequential Access Peripheral driver for CAM.
3  *
4  * Copyright (c) 1999, 2000 Matthew Jacob
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification, immediately at the beginning of the file.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
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/time.h>
40 #include <sys/bio.h>
41 #include <sys/limits.h>
42 #include <sys/malloc.h>
43 #include <sys/mtio.h>
44 #ifdef _KERNEL
45 #include <sys/conf.h>
46 #include <sys/sysctl.h>
47 #include <sys/taskqueue.h>
48 #endif
49 #include <sys/fcntl.h>
50 #include <sys/devicestat.h>
51 
52 #ifndef _KERNEL
53 #include <stdio.h>
54 #include <string.h>
55 #endif
56 
57 #include <cam/cam.h>
58 #include <cam/cam_ccb.h>
59 #include <cam/cam_periph.h>
60 #include <cam/cam_xpt_periph.h>
61 #include <cam/cam_debug.h>
62 
63 #include <cam/scsi/scsi_all.h>
64 #include <cam/scsi/scsi_message.h>
65 #include <cam/scsi/scsi_sa.h>
66 
67 #ifdef _KERNEL
68 
69 #include <opt_sa.h>
70 
71 #ifndef SA_IO_TIMEOUT
72 #define SA_IO_TIMEOUT		4
73 #endif
74 #ifndef SA_SPACE_TIMEOUT
75 #define SA_SPACE_TIMEOUT	1 * 60
76 #endif
77 #ifndef SA_REWIND_TIMEOUT
78 #define SA_REWIND_TIMEOUT	2 * 60
79 #endif
80 #ifndef SA_ERASE_TIMEOUT
81 #define SA_ERASE_TIMEOUT	4 * 60
82 #endif
83 
84 #define	SCSIOP_TIMEOUT		(60 * 1000)	/* not an option */
85 
86 #define	IO_TIMEOUT		(SA_IO_TIMEOUT * 60 * 1000)
87 #define	REWIND_TIMEOUT		(SA_REWIND_TIMEOUT * 60 * 1000)
88 #define	ERASE_TIMEOUT		(SA_ERASE_TIMEOUT * 60 * 1000)
89 #define	SPACE_TIMEOUT		(SA_SPACE_TIMEOUT * 60 * 1000)
90 
91 /*
92  * Additional options that can be set for config: SA_1FM_AT_EOT
93  */
94 
95 #ifndef	UNUSED_PARAMETER
96 #define	UNUSED_PARAMETER(x)	x = x
97 #endif
98 
99 #define	QFRLS(ccb)	\
100 	if (((ccb)->ccb_h.status & CAM_DEV_QFRZN) != 0)	\
101 		cam_release_devq((ccb)->ccb_h.path, 0, 0, 0, FALSE)
102 
103 /*
104  * Driver states
105  */
106 
107 static MALLOC_DEFINE(M_SCSISA, "SCSI sa", "SCSI sequential access buffers");
108 
109 typedef enum {
110 	SA_STATE_NORMAL, SA_STATE_ABNORMAL
111 } sa_state;
112 
113 #define ccb_pflags	ppriv_field0
114 #define ccb_bp	 	ppriv_ptr1
115 
116 /* bits in ccb_pflags */
117 #define	SA_POSITION_UPDATED	0x1
118 
119 
120 typedef enum {
121 	SA_FLAG_OPEN		= 0x0001,
122 	SA_FLAG_FIXED		= 0x0002,
123 	SA_FLAG_TAPE_LOCKED	= 0x0004,
124 	SA_FLAG_TAPE_MOUNTED	= 0x0008,
125 	SA_FLAG_TAPE_WP		= 0x0010,
126 	SA_FLAG_TAPE_WRITTEN	= 0x0020,
127 	SA_FLAG_EOM_PENDING	= 0x0040,
128 	SA_FLAG_EIO_PENDING	= 0x0080,
129 	SA_FLAG_EOF_PENDING	= 0x0100,
130 	SA_FLAG_ERR_PENDING	= (SA_FLAG_EOM_PENDING|SA_FLAG_EIO_PENDING|
131 				   SA_FLAG_EOF_PENDING),
132 	SA_FLAG_INVALID		= 0x0200,
133 	SA_FLAG_COMP_ENABLED	= 0x0400,
134 	SA_FLAG_COMP_SUPP	= 0x0800,
135 	SA_FLAG_COMP_UNSUPP	= 0x1000,
136 	SA_FLAG_TAPE_FROZEN	= 0x2000
137 } sa_flags;
138 
139 typedef enum {
140 	SA_MODE_REWIND		= 0x00,
141 	SA_MODE_NOREWIND	= 0x01,
142 	SA_MODE_OFFLINE		= 0x02
143 } sa_mode;
144 
145 typedef enum {
146 	SA_PARAM_NONE		= 0x00,
147 	SA_PARAM_BLOCKSIZE	= 0x01,
148 	SA_PARAM_DENSITY	= 0x02,
149 	SA_PARAM_COMPRESSION	= 0x04,
150 	SA_PARAM_BUFF_MODE	= 0x08,
151 	SA_PARAM_NUMBLOCKS	= 0x10,
152 	SA_PARAM_WP		= 0x20,
153 	SA_PARAM_SPEED		= 0x40,
154 	SA_PARAM_ALL		= 0x7f
155 } sa_params;
156 
157 typedef enum {
158 	SA_QUIRK_NONE		= 0x00,
159 	SA_QUIRK_NOCOMP		= 0x01,	/* Can't deal with compression at all */
160 	SA_QUIRK_FIXED		= 0x02,	/* Force fixed mode */
161 	SA_QUIRK_VARIABLE	= 0x04,	/* Force variable mode */
162 	SA_QUIRK_2FM		= 0x08,	/* Needs Two File Marks at EOD */
163 	SA_QUIRK_1FM		= 0x10,	/* No more than 1 File Mark at EOD */
164 	SA_QUIRK_NODREAD	= 0x20,	/* Don't try and dummy read density */
165 	SA_QUIRK_NO_MODESEL	= 0x40,	/* Don't do mode select at all */
166 	SA_QUIRK_NO_CPAGE	= 0x80	/* Don't use DEVICE COMPRESSION page */
167 } sa_quirks;
168 
169 #define SA_QUIRK_BIT_STRING	\
170 	"\020"			\
171 	"\001NOCOMP"		\
172 	"\002FIXED"		\
173 	"\003VARIABLE"		\
174 	"\0042FM"		\
175 	"\0051FM"		\
176 	"\006NODREAD"		\
177 	"\007NO_MODESEL"	\
178 	"\010NO_CPAGE"
179 
180 #define	SAMODE(z)	(dev2unit(z) & 0x3)
181 #define	SADENSITY(z)	((dev2unit(z) >> 2) & 0x3)
182 #define	SA_IS_CTRL(z)	(dev2unit(z) & (1 << 4))
183 
184 #define SA_NOT_CTLDEV	0
185 #define SA_CTLDEV	1
186 
187 #define SA_ATYPE_R	0
188 #define SA_ATYPE_NR	1
189 #define SA_ATYPE_ER	2
190 
191 #define	SAMINOR(ctl, mode, access) \
192 	((ctl << 4) | (mode << 2) | (access & 0x3))
193 
194 #define SA_NUM_MODES	4
195 struct sa_devs {
196 	struct cdev *ctl_dev;
197 	struct sa_mode_devs {
198 		struct cdev *r_dev;
199 		struct cdev *nr_dev;
200 		struct cdev *er_dev;
201 	} mode_devs[SA_NUM_MODES];
202 };
203 
204 struct sa_softc {
205 	sa_state	state;
206 	sa_flags	flags;
207 	sa_quirks	quirks;
208 	u_int		si_flags;
209 	struct		bio_queue_head bio_queue;
210 	int		queue_count;
211 	struct		devstat *device_stats;
212 	struct sa_devs	devs;
213 	int		blk_gran;
214 	int		blk_mask;
215 	int		blk_shift;
216 	u_int32_t	max_blk;
217 	u_int32_t	min_blk;
218 	u_int32_t	maxio;
219 	u_int32_t	cpi_maxio;
220 	int		allow_io_split;
221 	u_int32_t	comp_algorithm;
222 	u_int32_t	saved_comp_algorithm;
223 	u_int32_t	media_blksize;
224 	u_int32_t	last_media_blksize;
225 	u_int32_t	media_numblks;
226 	u_int8_t	media_density;
227 	u_int8_t	speed;
228 	u_int8_t	scsi_rev;
229 	u_int8_t	dsreg;		/* mtio mt_dsreg, redux */
230 	int		buffer_mode;
231 	int		filemarks;
232 	union		ccb saved_ccb;
233 	int		last_resid_was_io;
234 
235 	/*
236 	 * Relative to BOT Location.
237 	 */
238 	daddr_t		fileno;
239 	daddr_t		blkno;
240 
241 	/*
242 	 * Latched Error Info
243 	 */
244 	struct {
245 		struct scsi_sense_data _last_io_sense;
246 		u_int64_t _last_io_resid;
247 		u_int8_t _last_io_cdb[CAM_MAX_CDBLEN];
248 		struct scsi_sense_data _last_ctl_sense;
249 		u_int64_t _last_ctl_resid;
250 		u_int8_t _last_ctl_cdb[CAM_MAX_CDBLEN];
251 #define	last_io_sense	errinfo._last_io_sense
252 #define	last_io_resid	errinfo._last_io_resid
253 #define	last_io_cdb	errinfo._last_io_cdb
254 #define	last_ctl_sense	errinfo._last_ctl_sense
255 #define	last_ctl_resid	errinfo._last_ctl_resid
256 #define	last_ctl_cdb	errinfo._last_ctl_cdb
257 	} errinfo;
258 	/*
259 	 * Misc other flags/state
260 	 */
261 	u_int32_t
262 					: 29,
263 		open_rdonly		: 1,	/* open read-only */
264 		open_pending_mount	: 1,	/* open pending mount */
265 		ctrl_mode		: 1;	/* control device open */
266 
267 	struct task		sysctl_task;
268 	struct sysctl_ctx_list	sysctl_ctx;
269 	struct sysctl_oid	*sysctl_tree;
270 };
271 
272 struct sa_quirk_entry {
273 	struct scsi_inquiry_pattern inq_pat;	/* matching pattern */
274 	sa_quirks quirks;	/* specific quirk type */
275 	u_int32_t prefblk;	/* preferred blocksize when in fixed mode */
276 };
277 
278 static struct sa_quirk_entry sa_quirk_table[] =
279 {
280 	{
281 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "OnStream",
282 		  "ADR*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_NODREAD |
283 		   SA_QUIRK_1FM|SA_QUIRK_NO_MODESEL, 32768
284 	},
285 	{
286 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
287 		  "Python 06408*", "*"}, SA_QUIRK_NODREAD, 0
288 	},
289 	{
290 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
291 		  "Python 25601*", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_NODREAD, 0
292 	},
293 	{
294 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
295 		  "Python*", "*"}, SA_QUIRK_NODREAD, 0
296 	},
297 	{
298 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
299 		  "VIPER 150*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
300 	},
301 	{
302 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
303 		  "VIPER 2525 25462", "-011"},
304 		  SA_QUIRK_NOCOMP|SA_QUIRK_1FM|SA_QUIRK_NODREAD, 0
305 	},
306 	{
307 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "ARCHIVE",
308 		  "VIPER 2525*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 1024
309 	},
310 #if	0
311 	{
312 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
313 		  "C15*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_NO_CPAGE, 0,
314 	},
315 #endif
316  	{
317  		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
318 		  "C56*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
319 	},
320 	{
321 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
322 		  "T20*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
323 	},
324 	{
325 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
326 		  "T4000*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
327 	},
328 	{
329 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "HP",
330 		  "HP-88780*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
331 	},
332 	{
333 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "KENNEDY",
334 		  "*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
335 	},
336 	{
337 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "M4 DATA",
338 		  "123107 SCSI*", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
339 	},
340 	{	/* jreynold@primenet.com */
341 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "Seagate",
342 		"STT8000N*", "*"}, SA_QUIRK_1FM, 0
343 	},
344 	{	/* mike@sentex.net */
345 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "Seagate",
346 		"STT20000*", "*"}, SA_QUIRK_1FM, 0
347 	},
348 	{
349 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "SEAGATE",
350 		"DAT    06241-XXX", "*"}, SA_QUIRK_VARIABLE|SA_QUIRK_2FM, 0
351 	},
352 	{
353 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
354 		  " TDC 3600", "U07:"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
355 	},
356 	{
357 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
358 		  " TDC 3800", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
359 	},
360 	{
361 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
362 		  " TDC 4100", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
363 	},
364 	{
365 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
366 		  " TDC 4200", "*"}, SA_QUIRK_NOCOMP|SA_QUIRK_1FM, 512
367 	},
368 	{
369 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "TANDBERG",
370 		  " SLR*", "*"}, SA_QUIRK_1FM, 0
371 	},
372 	{
373 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "WANGTEK",
374 		  "5525ES*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 512
375 	},
376 	{
377 		{ T_SEQUENTIAL, SIP_MEDIA_REMOVABLE, "WANGTEK",
378 		  "51000*", "*"}, SA_QUIRK_FIXED|SA_QUIRK_1FM, 1024
379 	}
380 };
381 
382 static	d_open_t	saopen;
383 static	d_close_t	saclose;
384 static	d_strategy_t	sastrategy;
385 static	d_ioctl_t	saioctl;
386 static	periph_init_t	sainit;
387 static	periph_ctor_t	saregister;
388 static	periph_oninv_t	saoninvalidate;
389 static	periph_dtor_t	sacleanup;
390 static	periph_start_t	sastart;
391 static	void		saasync(void *callback_arg, u_int32_t code,
392 				struct cam_path *path, void *arg);
393 static	void		sadone(struct cam_periph *periph,
394 			       union ccb *start_ccb);
395 static  int		saerror(union ccb *ccb, u_int32_t cam_flags,
396 				u_int32_t sense_flags);
397 static int		samarkswanted(struct cam_periph *);
398 static int		sacheckeod(struct cam_periph *periph);
399 static int		sagetparams(struct cam_periph *periph,
400 				    sa_params params_to_get,
401 				    u_int32_t *blocksize, u_int8_t *density,
402 				    u_int32_t *numblocks, int *buff_mode,
403 				    u_int8_t *write_protect, u_int8_t *speed,
404 				    int *comp_supported, int *comp_enabled,
405 				    u_int32_t *comp_algorithm,
406 				    sa_comp_t *comp_page);
407 static int		sasetparams(struct cam_periph *periph,
408 				    sa_params params_to_set,
409 				    u_int32_t blocksize, u_int8_t density,
410 				    u_int32_t comp_algorithm,
411 				    u_int32_t sense_flags);
412 static void		saprevent(struct cam_periph *periph, int action);
413 static int		sarewind(struct cam_periph *periph);
414 static int		saspace(struct cam_periph *periph, int count,
415 				scsi_space_code code);
416 static int		samount(struct cam_periph *, int, struct cdev *);
417 static int		saretension(struct cam_periph *periph);
418 static int		sareservereleaseunit(struct cam_periph *periph,
419 					     int reserve);
420 static int		saloadunload(struct cam_periph *periph, int load);
421 static int		saerase(struct cam_periph *periph, int longerase);
422 static int		sawritefilemarks(struct cam_periph *periph,
423 					 int nmarks, int setmarks);
424 static int		sardpos(struct cam_periph *periph, int, u_int32_t *);
425 static int		sasetpos(struct cam_periph *periph, int, u_int32_t *);
426 
427 
428 #ifndef	SA_DEFAULT_IO_SPLIT
429 #define	SA_DEFAULT_IO_SPLIT	0
430 #endif
431 
432 static int sa_allow_io_split = SA_DEFAULT_IO_SPLIT;
433 
434 /*
435  * Tunable to allow the user to set a global allow_io_split value.  Note
436  * that this WILL GO AWAY in FreeBSD 11.0.  Silently splitting the I/O up
437  * is bad behavior, because it hides the true tape block size from the
438  * application.
439  */
440 static SYSCTL_NODE(_kern_cam, OID_AUTO, sa, CTLFLAG_RD, 0,
441 		  "CAM Sequential Access Tape Driver");
442 SYSCTL_INT(_kern_cam_sa, OID_AUTO, allow_io_split, CTLFLAG_RDTUN,
443     &sa_allow_io_split, 0, "Default I/O split value");
444 
445 static struct periph_driver sadriver =
446 {
447 	sainit, "sa",
448 	TAILQ_HEAD_INITIALIZER(sadriver.units), /* generation */ 0
449 };
450 
451 PERIPHDRIVER_DECLARE(sa, sadriver);
452 
453 /* For 2.2-stable support */
454 #ifndef D_TAPE
455 #define D_TAPE 0
456 #endif
457 
458 
459 static struct cdevsw sa_cdevsw = {
460 	.d_version =	D_VERSION,
461 	.d_open =	saopen,
462 	.d_close =	saclose,
463 	.d_read =	physread,
464 	.d_write =	physwrite,
465 	.d_ioctl =	saioctl,
466 	.d_strategy =	sastrategy,
467 	.d_name =	"sa",
468 	.d_flags =	D_TAPE,
469 };
470 
471 static int
472 saopen(struct cdev *dev, int flags, int fmt, struct thread *td)
473 {
474 	struct cam_periph *periph;
475 	struct sa_softc *softc;
476 	int error;
477 
478 	periph = (struct cam_periph *)dev->si_drv1;
479 	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
480 		return (ENXIO);
481 	}
482 
483 	cam_periph_lock(periph);
484 
485 	softc = (struct sa_softc *)periph->softc;
486 
487 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE|CAM_DEBUG_INFO,
488 	    ("saopen(%s): softc=0x%x\n", devtoname(dev), softc->flags));
489 
490 	if (SA_IS_CTRL(dev)) {
491 		softc->ctrl_mode = 1;
492 		cam_periph_unlock(periph);
493 		return (0);
494 	}
495 
496 	if ((error = cam_periph_hold(periph, PRIBIO|PCATCH)) != 0) {
497 		cam_periph_unlock(periph);
498 		cam_periph_release(periph);
499 		return (error);
500 	}
501 
502 	if (softc->flags & SA_FLAG_OPEN) {
503 		error = EBUSY;
504 	} else if (softc->flags & SA_FLAG_INVALID) {
505 		error = ENXIO;
506 	} else {
507 		/*
508 		 * Preserve whether this is a read_only open.
509 		 */
510 		softc->open_rdonly = (flags & O_RDWR) == O_RDONLY;
511 
512 		/*
513 		 * The function samount ensures media is loaded and ready.
514 		 * It also does a device RESERVE if the tape isn't yet mounted.
515 		 *
516 		 * If the mount fails and this was a non-blocking open,
517 		 * make this a 'open_pending_mount' action.
518 		 */
519 		error = samount(periph, flags, dev);
520 		if (error && (flags & O_NONBLOCK)) {
521 			softc->flags |= SA_FLAG_OPEN;
522 			softc->open_pending_mount = 1;
523 			cam_periph_unhold(periph);
524 			cam_periph_unlock(periph);
525 			return (0);
526 		}
527 	}
528 
529 	if (error) {
530 		cam_periph_unhold(periph);
531 		cam_periph_unlock(periph);
532 		cam_periph_release(periph);
533 		return (error);
534 	}
535 
536 	saprevent(periph, PR_PREVENT);
537 	softc->flags |= SA_FLAG_OPEN;
538 
539 	cam_periph_unhold(periph);
540 	cam_periph_unlock(periph);
541 	return (error);
542 }
543 
544 static int
545 saclose(struct cdev *dev, int flag, int fmt, struct thread *td)
546 {
547 	struct	cam_periph *periph;
548 	struct	sa_softc *softc;
549 	int	mode, error, writing, tmp;
550 	int	closedbits = SA_FLAG_OPEN;
551 
552 	mode = SAMODE(dev);
553 	periph = (struct cam_periph *)dev->si_drv1;
554 	if (periph == NULL)
555 		return (ENXIO);
556 
557 	cam_periph_lock(periph);
558 
559 	softc = (struct sa_softc *)periph->softc;
560 
561 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE|CAM_DEBUG_INFO,
562 	    ("saclose(%s): softc=0x%x\n", devtoname(dev), softc->flags));
563 
564 
565 	softc->open_rdonly = 0;
566 	if (SA_IS_CTRL(dev)) {
567 		softc->ctrl_mode = 0;
568 		cam_periph_unlock(periph);
569 		cam_periph_release(periph);
570 		return (0);
571 	}
572 
573 	if (softc->open_pending_mount) {
574 		softc->flags &= ~SA_FLAG_OPEN;
575 		softc->open_pending_mount = 0;
576 		cam_periph_unlock(periph);
577 		cam_periph_release(periph);
578 		return (0);
579 	}
580 
581 	if ((error = cam_periph_hold(periph, PRIBIO)) != 0) {
582 		cam_periph_unlock(periph);
583 		return (error);
584 	}
585 
586 	/*
587 	 * Were we writing the tape?
588 	 */
589 	writing = (softc->flags & SA_FLAG_TAPE_WRITTEN) != 0;
590 
591 	/*
592 	 * See whether or not we need to write filemarks. If this
593 	 * fails, we probably have to assume we've lost tape
594 	 * position.
595 	 */
596 	error = sacheckeod(periph);
597 	if (error) {
598 		xpt_print(periph->path,
599 		    "failed to write terminating filemark(s)\n");
600 		softc->flags |= SA_FLAG_TAPE_FROZEN;
601 	}
602 
603 	/*
604 	 * Whatever we end up doing, allow users to eject tapes from here on.
605 	 */
606 	saprevent(periph, PR_ALLOW);
607 
608 	/*
609 	 * Decide how to end...
610 	 */
611 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0) {
612 		closedbits |= SA_FLAG_TAPE_FROZEN;
613 	} else switch (mode) {
614 	case SA_MODE_OFFLINE:
615 		/*
616 		 * An 'offline' close is an unconditional release of
617 		 * frozen && mount conditions, irrespective of whether
618 		 * these operations succeeded. The reason for this is
619 		 * to allow at least some kind of programmatic way
620 		 * around our state getting all fouled up. If somebody
621 		 * issues an 'offline' command, that will be allowed
622 		 * to clear state.
623 		 */
624 		(void) sarewind(periph);
625 		(void) saloadunload(periph, FALSE);
626 		closedbits |= SA_FLAG_TAPE_MOUNTED|SA_FLAG_TAPE_FROZEN;
627 		break;
628 	case SA_MODE_REWIND:
629 		/*
630 		 * If the rewind fails, return an error- if anyone cares,
631 		 * but not overwriting any previous error.
632 		 *
633 		 * We don't clear the notion of mounted here, but we do
634 		 * clear the notion of frozen if we successfully rewound.
635 		 */
636 		tmp = sarewind(periph);
637 		if (tmp) {
638 			if (error != 0)
639 				error = tmp;
640 		} else {
641 			closedbits |= SA_FLAG_TAPE_FROZEN;
642 		}
643 		break;
644 	case SA_MODE_NOREWIND:
645 		/*
646 		 * If we're not rewinding/unloading the tape, find out
647 		 * whether we need to back up over one of two filemarks
648 		 * we wrote (if we wrote two filemarks) so that appends
649 		 * from this point on will be sane.
650 		 */
651 		if (error == 0 && writing && (softc->quirks & SA_QUIRK_2FM)) {
652 			tmp = saspace(periph, -1, SS_FILEMARKS);
653 			if (tmp) {
654 				xpt_print(periph->path, "unable to backspace "
655 				    "over one of double filemarks at end of "
656 				    "tape\n");
657 				xpt_print(periph->path, "it is possible that "
658 				    "this device needs a SA_QUIRK_1FM quirk set"
659 				    "for it\n");
660 				softc->flags |= SA_FLAG_TAPE_FROZEN;
661 			}
662 		}
663 		break;
664 	default:
665 		xpt_print(periph->path, "unknown mode 0x%x in saclose\n", mode);
666 		/* NOTREACHED */
667 		break;
668 	}
669 
670 	/*
671 	 * We wish to note here that there are no more filemarks to be written.
672 	 */
673 	softc->filemarks = 0;
674 	softc->flags &= ~SA_FLAG_TAPE_WRITTEN;
675 
676 	/*
677 	 * And we are no longer open for business.
678 	 */
679 	softc->flags &= ~closedbits;
680 
681 	/*
682 	 * Inform users if tape state if frozen....
683 	 */
684 	if (softc->flags & SA_FLAG_TAPE_FROZEN) {
685 		xpt_print(periph->path, "tape is now frozen- use an OFFLINE, "
686 		    "REWIND or MTEOM command to clear this state.\n");
687 	}
688 
689 	/* release the device if it is no longer mounted */
690 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0)
691 		sareservereleaseunit(periph, FALSE);
692 
693 	cam_periph_unhold(periph);
694 	cam_periph_unlock(periph);
695 	cam_periph_release(periph);
696 
697 	return (error);
698 }
699 
700 /*
701  * Actually translate the requested transfer into one the physical driver
702  * can understand.  The transfer is described by a buf and will include
703  * only one physical transfer.
704  */
705 static void
706 sastrategy(struct bio *bp)
707 {
708 	struct cam_periph *periph;
709 	struct sa_softc *softc;
710 
711 	bp->bio_resid = bp->bio_bcount;
712 	if (SA_IS_CTRL(bp->bio_dev)) {
713 		biofinish(bp, NULL, EINVAL);
714 		return;
715 	}
716 	periph = (struct cam_periph *)bp->bio_dev->si_drv1;
717 	if (periph == NULL) {
718 		biofinish(bp, NULL, ENXIO);
719 		return;
720 	}
721 	cam_periph_lock(periph);
722 
723 	softc = (struct sa_softc *)periph->softc;
724 
725 	if (softc->flags & SA_FLAG_INVALID) {
726 		cam_periph_unlock(periph);
727 		biofinish(bp, NULL, ENXIO);
728 		return;
729 	}
730 
731 	if (softc->flags & SA_FLAG_TAPE_FROZEN) {
732 		cam_periph_unlock(periph);
733 		biofinish(bp, NULL, EPERM);
734 		return;
735 	}
736 
737 	/*
738 	 * This should actually never occur as the write(2)
739 	 * system call traps attempts to write to a read-only
740 	 * file descriptor.
741 	 */
742 	if (bp->bio_cmd == BIO_WRITE && softc->open_rdonly) {
743 		cam_periph_unlock(periph);
744 		biofinish(bp, NULL, EBADF);
745 		return;
746 	}
747 
748 	if (softc->open_pending_mount) {
749 		int error = samount(periph, 0, bp->bio_dev);
750 		if (error) {
751 			cam_periph_unlock(periph);
752 			biofinish(bp, NULL, ENXIO);
753 			return;
754 		}
755 		saprevent(periph, PR_PREVENT);
756 		softc->open_pending_mount = 0;
757 	}
758 
759 
760 	/*
761 	 * If it's a null transfer, return immediately
762 	 */
763 	if (bp->bio_bcount == 0) {
764 		cam_periph_unlock(periph);
765 		biodone(bp);
766 		return;
767 	}
768 
769 	/* valid request?  */
770 	if (softc->flags & SA_FLAG_FIXED) {
771 		/*
772 		 * Fixed block device.  The byte count must
773 		 * be a multiple of our block size.
774 		 */
775 		if (((softc->blk_mask != ~0) &&
776 		    ((bp->bio_bcount & softc->blk_mask) != 0)) ||
777 		    ((softc->blk_mask == ~0) &&
778 		    ((bp->bio_bcount % softc->min_blk) != 0))) {
779 			xpt_print(periph->path, "Invalid request.  Fixed block "
780 			    "device requests must be a multiple of %d bytes\n",
781 			    softc->min_blk);
782 			cam_periph_unlock(periph);
783 			biofinish(bp, NULL, EINVAL);
784 			return;
785 		}
786 	} else if ((bp->bio_bcount > softc->max_blk) ||
787 		   (bp->bio_bcount < softc->min_blk) ||
788 		   (bp->bio_bcount & softc->blk_mask) != 0) {
789 
790 		xpt_print_path(periph->path);
791 		printf("Invalid request.  Variable block "
792 		    "device requests must be ");
793 		if (softc->blk_mask != 0) {
794 			printf("a multiple of %d ", (0x1 << softc->blk_gran));
795 		}
796 		printf("between %d and %d bytes\n", softc->min_blk,
797 		    softc->max_blk);
798 		cam_periph_unlock(periph);
799 		biofinish(bp, NULL, EINVAL);
800 		return;
801         }
802 
803 	/*
804 	 * Place it at the end of the queue.
805 	 */
806 	bioq_insert_tail(&softc->bio_queue, bp);
807 	softc->queue_count++;
808 #if	0
809 	CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
810 	    ("sastrategy: queuing a %ld %s byte %s\n", bp->bio_bcount,
811  	    (softc->flags & SA_FLAG_FIXED)?  "fixed" : "variable",
812 	    (bp->bio_cmd == BIO_READ)? "read" : "write"));
813 #endif
814 	if (softc->queue_count > 1) {
815 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
816 		    ("sastrategy: queue count now %d\n", softc->queue_count));
817 	}
818 
819 	/*
820 	 * Schedule ourselves for performing the work.
821 	 */
822 	xpt_schedule(periph, CAM_PRIORITY_NORMAL);
823 	cam_periph_unlock(periph);
824 
825 	return;
826 }
827 
828 
829 #define	PENDING_MOUNT_CHECK(softc, periph, dev)		\
830 	if (softc->open_pending_mount) {		\
831 		error = samount(periph, 0, dev);	\
832 		if (error) {				\
833 			break;				\
834 		}					\
835 		saprevent(periph, PR_PREVENT);		\
836 		softc->open_pending_mount = 0;		\
837 	}
838 
839 static int
840 saioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td)
841 {
842 	struct cam_periph *periph;
843 	struct sa_softc *softc;
844 	scsi_space_code spaceop;
845 	int didlockperiph = 0;
846 	int mode;
847 	int error = 0;
848 
849 	mode = SAMODE(dev);
850 	error = 0;		/* shut up gcc */
851 	spaceop = 0;		/* shut up gcc */
852 
853 	periph = (struct cam_periph *)dev->si_drv1;
854 	if (periph == NULL)
855 		return (ENXIO);
856 
857 	cam_periph_lock(periph);
858 	softc = (struct sa_softc *)periph->softc;
859 
860 	/*
861 	 * Check for control mode accesses. We allow MTIOCGET and
862 	 * MTIOCERRSTAT (but need to be the only one open in order
863 	 * to clear latched status), and MTSETBSIZE, MTSETDNSTY
864 	 * and MTCOMP (but need to be the only one accessing this
865 	 * device to run those).
866 	 */
867 
868 	if (SA_IS_CTRL(dev)) {
869 		switch (cmd) {
870 		case MTIOCGETEOTMODEL:
871 		case MTIOCGET:
872 			break;
873 		case MTIOCERRSTAT:
874 			/*
875 			 * If the periph isn't already locked, lock it
876 			 * so our MTIOCERRSTAT can reset latched error stats.
877 			 *
878 			 * If the periph is already locked, skip it because
879 			 * we're just getting status and it'll be up to the
880 			 * other thread that has this device open to do
881 			 * an MTIOCERRSTAT that would clear latched status.
882 			 */
883 			if ((periph->flags & CAM_PERIPH_LOCKED) == 0) {
884 				error = cam_periph_hold(periph, PRIBIO|PCATCH);
885 				if (error != 0) {
886 					cam_periph_unlock(periph);
887 					return (error);
888 				}
889 				didlockperiph = 1;
890 			}
891 			break;
892 
893 		case MTIOCTOP:
894 		{
895 			struct mtop *mt = (struct mtop *) arg;
896 
897 			/*
898 			 * Check to make sure it's an OP we can perform
899 			 * with no media inserted.
900 			 */
901 			switch (mt->mt_op) {
902 			case MTSETBSIZ:
903 			case MTSETDNSTY:
904 			case MTCOMP:
905 				mt = NULL;
906 				/* FALLTHROUGH */
907 			default:
908 				break;
909 			}
910 			if (mt != NULL) {
911 				break;
912 			}
913 			/* FALLTHROUGH */
914 		}
915 		case MTIOCSETEOTMODEL:
916 			/*
917 			 * We need to acquire the peripheral here rather
918 			 * than at open time because we are sharing writable
919 			 * access to data structures.
920 			 */
921 			error = cam_periph_hold(periph, PRIBIO|PCATCH);
922 			if (error != 0) {
923 				cam_periph_unlock(periph);
924 				return (error);
925 			}
926 			didlockperiph = 1;
927 			break;
928 
929 		default:
930 			cam_periph_unlock(periph);
931 			return (EINVAL);
932 		}
933 	}
934 
935 	/*
936 	 * Find the device that the user is talking about
937 	 */
938 	switch (cmd) {
939 	case MTIOCGET:
940 	{
941 		struct mtget *g = (struct mtget *)arg;
942 
943 		/*
944 		 * If this isn't the control mode device, actually go out
945 		 * and ask the drive again what it's set to.
946 		 */
947 		if (!SA_IS_CTRL(dev) && !softc->open_pending_mount) {
948 			u_int8_t write_protect;
949 			int comp_enabled, comp_supported;
950 			error = sagetparams(periph, SA_PARAM_ALL,
951 			    &softc->media_blksize, &softc->media_density,
952 			    &softc->media_numblks, &softc->buffer_mode,
953 			    &write_protect, &softc->speed, &comp_supported,
954 			    &comp_enabled, &softc->comp_algorithm, NULL);
955 			if (error)
956 				break;
957 			if (write_protect)
958 				softc->flags |= SA_FLAG_TAPE_WP;
959 			else
960 				softc->flags &= ~SA_FLAG_TAPE_WP;
961 			softc->flags &= ~(SA_FLAG_COMP_SUPP|
962 			    SA_FLAG_COMP_ENABLED|SA_FLAG_COMP_UNSUPP);
963 			if (comp_supported) {
964 				if (softc->saved_comp_algorithm == 0)
965 					softc->saved_comp_algorithm =
966 					    softc->comp_algorithm;
967 				softc->flags |= SA_FLAG_COMP_SUPP;
968 				if (comp_enabled)
969 					softc->flags |= SA_FLAG_COMP_ENABLED;
970 			} else
971 				softc->flags |= SA_FLAG_COMP_UNSUPP;
972 		}
973 		bzero(g, sizeof(struct mtget));
974 		g->mt_type = MT_ISAR;
975 		if (softc->flags & SA_FLAG_COMP_UNSUPP) {
976 			g->mt_comp = MT_COMP_UNSUPP;
977 			g->mt_comp0 = MT_COMP_UNSUPP;
978 			g->mt_comp1 = MT_COMP_UNSUPP;
979 			g->mt_comp2 = MT_COMP_UNSUPP;
980 			g->mt_comp3 = MT_COMP_UNSUPP;
981 		} else {
982 			if ((softc->flags & SA_FLAG_COMP_ENABLED) == 0) {
983 				g->mt_comp = MT_COMP_DISABLED;
984 			} else {
985 				g->mt_comp = softc->comp_algorithm;
986 			}
987 			g->mt_comp0 = softc->comp_algorithm;
988 			g->mt_comp1 = softc->comp_algorithm;
989 			g->mt_comp2 = softc->comp_algorithm;
990 			g->mt_comp3 = softc->comp_algorithm;
991 		}
992 		g->mt_density = softc->media_density;
993 		g->mt_density0 = softc->media_density;
994 		g->mt_density1 = softc->media_density;
995 		g->mt_density2 = softc->media_density;
996 		g->mt_density3 = softc->media_density;
997 		g->mt_blksiz = softc->media_blksize;
998 		g->mt_blksiz0 = softc->media_blksize;
999 		g->mt_blksiz1 = softc->media_blksize;
1000 		g->mt_blksiz2 = softc->media_blksize;
1001 		g->mt_blksiz3 = softc->media_blksize;
1002 		g->mt_fileno = softc->fileno;
1003 		g->mt_blkno = softc->blkno;
1004 		g->mt_dsreg = (short) softc->dsreg;
1005 		/*
1006 		 * Yes, we know that this is likely to overflow
1007 		 */
1008 		if (softc->last_resid_was_io) {
1009 			if ((g->mt_resid = (short) softc->last_io_resid) != 0) {
1010 				if (SA_IS_CTRL(dev) == 0 || didlockperiph) {
1011 					softc->last_io_resid = 0;
1012 				}
1013 			}
1014 		} else {
1015 			if ((g->mt_resid = (short)softc->last_ctl_resid) != 0) {
1016 				if (SA_IS_CTRL(dev) == 0 || didlockperiph) {
1017 					softc->last_ctl_resid = 0;
1018 				}
1019 			}
1020 		}
1021 		error = 0;
1022 		break;
1023 	}
1024 	case MTIOCERRSTAT:
1025 	{
1026 		struct scsi_tape_errors *sep =
1027 		    &((union mterrstat *)arg)->scsi_errstat;
1028 
1029 		CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
1030 		    ("saioctl: MTIOCERRSTAT\n"));
1031 
1032 		bzero(sep, sizeof(*sep));
1033 		sep->io_resid = softc->last_io_resid;
1034 		bcopy((caddr_t) &softc->last_io_sense, sep->io_sense,
1035 		    sizeof (sep->io_sense));
1036 		bcopy((caddr_t) &softc->last_io_cdb, sep->io_cdb,
1037 		    sizeof (sep->io_cdb));
1038 		sep->ctl_resid = softc->last_ctl_resid;
1039 		bcopy((caddr_t) &softc->last_ctl_sense, sep->ctl_sense,
1040 		    sizeof (sep->ctl_sense));
1041 		bcopy((caddr_t) &softc->last_ctl_cdb, sep->ctl_cdb,
1042 		    sizeof (sep->ctl_cdb));
1043 
1044 		if ((SA_IS_CTRL(dev) == 0 && softc->open_pending_mount) ||
1045 		    didlockperiph)
1046 			bzero((caddr_t) &softc->errinfo,
1047 			    sizeof (softc->errinfo));
1048 		error = 0;
1049 		break;
1050 	}
1051 	case MTIOCTOP:
1052 	{
1053 		struct mtop *mt;
1054 		int    count;
1055 
1056 		PENDING_MOUNT_CHECK(softc, periph, dev);
1057 
1058 		mt = (struct mtop *)arg;
1059 
1060 
1061 		CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
1062 			 ("saioctl: op=0x%x count=0x%x\n",
1063 			  mt->mt_op, mt->mt_count));
1064 
1065 		count = mt->mt_count;
1066 		switch (mt->mt_op) {
1067 		case MTWEOF:	/* write an end-of-file marker */
1068 			/*
1069 			 * We don't need to clear the SA_FLAG_TAPE_WRITTEN
1070 			 * flag because by keeping track of filemarks
1071 			 * we have last written we know ehether or not
1072 			 * we need to write more when we close the device.
1073 			 */
1074 			error = sawritefilemarks(periph, count, FALSE);
1075 			break;
1076 		case MTWSS:	/* write a setmark */
1077 			error = sawritefilemarks(periph, count, TRUE);
1078 			break;
1079 		case MTBSR:	/* backward space record */
1080 		case MTFSR:	/* forward space record */
1081 		case MTBSF:	/* backward space file */
1082 		case MTFSF:	/* forward space file */
1083 		case MTBSS:	/* backward space setmark */
1084 		case MTFSS:	/* forward space setmark */
1085 		case MTEOD:	/* space to end of recorded medium */
1086 		{
1087 			int nmarks;
1088 
1089 			spaceop = SS_FILEMARKS;
1090 			nmarks = softc->filemarks;
1091 			error = sacheckeod(periph);
1092 			if (error) {
1093 				xpt_print(periph->path,
1094 				    "EOD check prior to spacing failed\n");
1095 				softc->flags |= SA_FLAG_EIO_PENDING;
1096 				break;
1097 			}
1098 			nmarks -= softc->filemarks;
1099 			switch(mt->mt_op) {
1100 			case MTBSR:
1101 				count = -count;
1102 				/* FALLTHROUGH */
1103 			case MTFSR:
1104 				spaceop = SS_BLOCKS;
1105 				break;
1106 			case MTBSF:
1107 				count = -count;
1108 				/* FALLTHROUGH */
1109 			case MTFSF:
1110 				break;
1111 			case MTBSS:
1112 				count = -count;
1113 				/* FALLTHROUGH */
1114 			case MTFSS:
1115 				spaceop = SS_SETMARKS;
1116 				break;
1117 			case MTEOD:
1118 				spaceop = SS_EOD;
1119 				count = 0;
1120 				nmarks = 0;
1121 				break;
1122 			default:
1123 				error = EINVAL;
1124 				break;
1125 			}
1126 			if (error)
1127 				break;
1128 
1129 			nmarks = softc->filemarks;
1130 			/*
1131 			 * XXX: Why are we checking again?
1132 			 */
1133 			error = sacheckeod(periph);
1134 			if (error)
1135 				break;
1136 			nmarks -= softc->filemarks;
1137 			error = saspace(periph, count - nmarks, spaceop);
1138 			/*
1139 			 * At this point, clear that we've written the tape
1140 			 * and that we've written any filemarks. We really
1141 			 * don't know what the applications wishes to do next-
1142 			 * the sacheckeod's will make sure we terminated the
1143 			 * tape correctly if we'd been writing, but the next
1144 			 * action the user application takes will set again
1145 			 * whether we need to write filemarks.
1146 			 */
1147 			softc->flags &=
1148 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1149 			softc->filemarks = 0;
1150 			break;
1151 		}
1152 		case MTREW:	/* rewind */
1153 			PENDING_MOUNT_CHECK(softc, periph, dev);
1154 			(void) sacheckeod(periph);
1155 			error = sarewind(periph);
1156 			/* see above */
1157 			softc->flags &=
1158 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1159 			softc->flags &= ~SA_FLAG_ERR_PENDING;
1160 			softc->filemarks = 0;
1161 			break;
1162 		case MTERASE:	/* erase */
1163 			PENDING_MOUNT_CHECK(softc, periph, dev);
1164 			error = saerase(periph, count);
1165 			softc->flags &=
1166 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1167 			softc->flags &= ~SA_FLAG_ERR_PENDING;
1168 			break;
1169 		case MTRETENS:	/* re-tension tape */
1170 			PENDING_MOUNT_CHECK(softc, periph, dev);
1171 			error = saretension(periph);
1172 			softc->flags &=
1173 			    ~(SA_FLAG_TAPE_WRITTEN|SA_FLAG_TAPE_FROZEN);
1174 			softc->flags &= ~SA_FLAG_ERR_PENDING;
1175 			break;
1176 		case MTOFFL:	/* rewind and put the drive offline */
1177 
1178 			PENDING_MOUNT_CHECK(softc, periph, dev);
1179 
1180 			(void) sacheckeod(periph);
1181 			/* see above */
1182 			softc->flags &= ~SA_FLAG_TAPE_WRITTEN;
1183 			softc->filemarks = 0;
1184 
1185 			error = sarewind(periph);
1186 			/* clear the frozen flag anyway */
1187 			softc->flags &= ~SA_FLAG_TAPE_FROZEN;
1188 
1189 			/*
1190 			 * Be sure to allow media removal before ejecting.
1191 			 */
1192 
1193 			saprevent(periph, PR_ALLOW);
1194 			if (error == 0) {
1195 				error = saloadunload(periph, FALSE);
1196 				if (error == 0) {
1197 					softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1198 				}
1199 			}
1200 			break;
1201 
1202 		case MTNOP:	/* no operation, sets status only */
1203 		case MTCACHE:	/* enable controller cache */
1204 		case MTNOCACHE:	/* disable controller cache */
1205 			error = 0;
1206 			break;
1207 
1208 		case MTSETBSIZ:	/* Set block size for device */
1209 
1210 			PENDING_MOUNT_CHECK(softc, periph, dev);
1211 
1212 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE, count,
1213 					    0, 0, 0);
1214 			if (error == 0) {
1215 				softc->last_media_blksize =
1216 				    softc->media_blksize;
1217 				softc->media_blksize = count;
1218 				if (count) {
1219 					softc->flags |= SA_FLAG_FIXED;
1220 					if (powerof2(count)) {
1221 						softc->blk_shift =
1222 						    ffs(count) - 1;
1223 						softc->blk_mask = count - 1;
1224 					} else {
1225 						softc->blk_mask = ~0;
1226 						softc->blk_shift = 0;
1227 					}
1228 					/*
1229 					 * Make the user's desire 'persistent'.
1230 					 */
1231 					softc->quirks &= ~SA_QUIRK_VARIABLE;
1232 					softc->quirks |= SA_QUIRK_FIXED;
1233 				} else {
1234 					softc->flags &= ~SA_FLAG_FIXED;
1235 					if (softc->max_blk == 0) {
1236 						softc->max_blk = ~0;
1237 					}
1238 					softc->blk_shift = 0;
1239 					if (softc->blk_gran != 0) {
1240 						softc->blk_mask =
1241 						    softc->blk_gran - 1;
1242 					} else {
1243 						softc->blk_mask = 0;
1244 					}
1245 					/*
1246 					 * Make the user's desire 'persistent'.
1247 					 */
1248 					softc->quirks |= SA_QUIRK_VARIABLE;
1249 					softc->quirks &= ~SA_QUIRK_FIXED;
1250 				}
1251 			}
1252 			break;
1253 		case MTSETDNSTY:	/* Set density for device and mode */
1254 			PENDING_MOUNT_CHECK(softc, periph, dev);
1255 
1256 			if (count > UCHAR_MAX) {
1257 				error = EINVAL;
1258 				break;
1259 			} else {
1260 				error = sasetparams(periph, SA_PARAM_DENSITY,
1261 						    0, count, 0, 0);
1262 			}
1263 			break;
1264 		case MTCOMP:	/* enable compression */
1265 			PENDING_MOUNT_CHECK(softc, periph, dev);
1266 			/*
1267 			 * Some devices don't support compression, and
1268 			 * don't like it if you ask them for the
1269 			 * compression page.
1270 			 */
1271 			if ((softc->quirks & SA_QUIRK_NOCOMP) ||
1272 			    (softc->flags & SA_FLAG_COMP_UNSUPP)) {
1273 				error = ENODEV;
1274 				break;
1275 			}
1276 			error = sasetparams(periph, SA_PARAM_COMPRESSION,
1277 			    0, 0, count, SF_NO_PRINT);
1278 			break;
1279 		default:
1280 			error = EINVAL;
1281 		}
1282 		break;
1283 	}
1284 	case MTIOCIEOT:
1285 	case MTIOCEEOT:
1286 		error = 0;
1287 		break;
1288 	case MTIOCRDSPOS:
1289 		PENDING_MOUNT_CHECK(softc, periph, dev);
1290 		error = sardpos(periph, 0, (u_int32_t *) arg);
1291 		break;
1292 	case MTIOCRDHPOS:
1293 		PENDING_MOUNT_CHECK(softc, periph, dev);
1294 		error = sardpos(periph, 1, (u_int32_t *) arg);
1295 		break;
1296 	case MTIOCSLOCATE:
1297 		PENDING_MOUNT_CHECK(softc, periph, dev);
1298 		error = sasetpos(periph, 0, (u_int32_t *) arg);
1299 		break;
1300 	case MTIOCHLOCATE:
1301 		PENDING_MOUNT_CHECK(softc, periph, dev);
1302 		error = sasetpos(periph, 1, (u_int32_t *) arg);
1303 		break;
1304 	case MTIOCGETEOTMODEL:
1305 		error = 0;
1306 		if (softc->quirks & SA_QUIRK_1FM)
1307 			mode = 1;
1308 		else
1309 			mode = 2;
1310 		*((u_int32_t *) arg) = mode;
1311 		break;
1312 	case MTIOCSETEOTMODEL:
1313 		error = 0;
1314 		switch (*((u_int32_t *) arg)) {
1315 		case 1:
1316 			softc->quirks &= ~SA_QUIRK_2FM;
1317 			softc->quirks |= SA_QUIRK_1FM;
1318 			break;
1319 		case 2:
1320 			softc->quirks &= ~SA_QUIRK_1FM;
1321 			softc->quirks |= SA_QUIRK_2FM;
1322 			break;
1323 		default:
1324 			error = EINVAL;
1325 			break;
1326 		}
1327 		break;
1328 	default:
1329 		error = cam_periph_ioctl(periph, cmd, arg, saerror);
1330 		break;
1331 	}
1332 
1333 	/*
1334 	 * Check to see if we cleared a frozen state
1335 	 */
1336 	if (error == 0 && (softc->flags & SA_FLAG_TAPE_FROZEN)) {
1337 		switch(cmd) {
1338 		case MTIOCRDSPOS:
1339 		case MTIOCRDHPOS:
1340 		case MTIOCSLOCATE:
1341 		case MTIOCHLOCATE:
1342 			softc->fileno = (daddr_t) -1;
1343 			softc->blkno = (daddr_t) -1;
1344 			softc->flags &= ~SA_FLAG_TAPE_FROZEN;
1345 			xpt_print(periph->path,
1346 			    "tape state now unfrozen.\n");
1347 			break;
1348 		default:
1349 			break;
1350 		}
1351 	}
1352 	if (didlockperiph) {
1353 		cam_periph_unhold(periph);
1354 	}
1355 	cam_periph_unlock(periph);
1356 	return (error);
1357 }
1358 
1359 static void
1360 sainit(void)
1361 {
1362 	cam_status status;
1363 
1364 	/*
1365 	 * Install a global async callback.
1366 	 */
1367 	status = xpt_register_async(AC_FOUND_DEVICE, saasync, NULL, NULL);
1368 
1369 	if (status != CAM_REQ_CMP) {
1370 		printf("sa: Failed to attach master async callback "
1371 		       "due to status 0x%x!\n", status);
1372 	}
1373 }
1374 
1375 static void
1376 saoninvalidate(struct cam_periph *periph)
1377 {
1378 	struct sa_softc *softc;
1379 
1380 	softc = (struct sa_softc *)periph->softc;
1381 
1382 	/*
1383 	 * De-register any async callbacks.
1384 	 */
1385 	xpt_register_async(0, saasync, periph, periph->path);
1386 
1387 	softc->flags |= SA_FLAG_INVALID;
1388 
1389 	/*
1390 	 * Return all queued I/O with ENXIO.
1391 	 * XXX Handle any transactions queued to the card
1392 	 *     with XPT_ABORT_CCB.
1393 	 */
1394 	bioq_flush(&softc->bio_queue, NULL, ENXIO);
1395 	softc->queue_count = 0;
1396 }
1397 
1398 static void
1399 sacleanup(struct cam_periph *periph)
1400 {
1401 	struct sa_softc *softc;
1402 	int i;
1403 
1404 	softc = (struct sa_softc *)periph->softc;
1405 
1406 	devstat_remove_entry(softc->device_stats);
1407 	cam_periph_unlock(periph);
1408 	destroy_dev(softc->devs.ctl_dev);
1409 	for (i = 0; i < SA_NUM_MODES; i++) {
1410 		destroy_dev(softc->devs.mode_devs[i].r_dev);
1411 		destroy_dev(softc->devs.mode_devs[i].nr_dev);
1412 		destroy_dev(softc->devs.mode_devs[i].er_dev);
1413 	}
1414 	cam_periph_lock(periph);
1415 	free(softc, M_SCSISA);
1416 }
1417 
1418 static void
1419 saasync(void *callback_arg, u_int32_t code,
1420 	struct cam_path *path, void *arg)
1421 {
1422 	struct cam_periph *periph;
1423 
1424 	periph = (struct cam_periph *)callback_arg;
1425 	switch (code) {
1426 	case AC_FOUND_DEVICE:
1427 	{
1428 		struct ccb_getdev *cgd;
1429 		cam_status status;
1430 
1431 		cgd = (struct ccb_getdev *)arg;
1432 		if (cgd == NULL)
1433 			break;
1434 
1435 		if (cgd->protocol != PROTO_SCSI)
1436 			break;
1437 
1438 		if (SID_TYPE(&cgd->inq_data) != T_SEQUENTIAL)
1439 			break;
1440 
1441 		/*
1442 		 * Allocate a peripheral instance for
1443 		 * this device and start the probe
1444 		 * process.
1445 		 */
1446 		status = cam_periph_alloc(saregister, saoninvalidate,
1447 					  sacleanup, sastart,
1448 					  "sa", CAM_PERIPH_BIO, path,
1449 					  saasync, AC_FOUND_DEVICE, cgd);
1450 
1451 		if (status != CAM_REQ_CMP
1452 		 && status != CAM_REQ_INPROG)
1453 			printf("saasync: Unable to probe new device "
1454 				"due to status 0x%x\n", status);
1455 		break;
1456 	}
1457 	default:
1458 		cam_periph_async(periph, code, path, arg);
1459 		break;
1460 	}
1461 }
1462 
1463 static void
1464 sasysctlinit(void *context, int pending)
1465 {
1466 	struct cam_periph *periph;
1467 	struct sa_softc *softc;
1468 	char tmpstr[80], tmpstr2[80];
1469 
1470 	periph = (struct cam_periph *)context;
1471 	/*
1472 	 * If the periph is invalid, no need to setup the sysctls.
1473 	 */
1474 	if (periph->flags & CAM_PERIPH_INVALID)
1475 		goto bailout;
1476 
1477 	softc = (struct sa_softc *)periph->softc;
1478 
1479 	snprintf(tmpstr, sizeof(tmpstr), "CAM SA unit %d", periph->unit_number);
1480 	snprintf(tmpstr2, sizeof(tmpstr2), "%u", periph->unit_number);
1481 
1482 	sysctl_ctx_init(&softc->sysctl_ctx);
1483 	softc->sysctl_tree = SYSCTL_ADD_NODE(&softc->sysctl_ctx,
1484 	    SYSCTL_STATIC_CHILDREN(_kern_cam_sa), OID_AUTO, tmpstr2,
1485                     CTLFLAG_RD, 0, tmpstr);
1486 	if (softc->sysctl_tree == NULL)
1487 		goto bailout;
1488 
1489 	SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
1490 	    OID_AUTO, "allow_io_split", CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
1491 	    &softc->allow_io_split, 0, "Allow Splitting I/O");
1492 	SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
1493 	    OID_AUTO, "maxio", CTLFLAG_RD,
1494 	    &softc->maxio, 0, "Maximum I/O size");
1495 	SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
1496 	    OID_AUTO, "cpi_maxio", CTLFLAG_RD,
1497 	    &softc->cpi_maxio, 0, "Maximum Controller I/O size");
1498 
1499 bailout:
1500 	/*
1501 	 * Release the reference that was held when this task was enqueued.
1502 	 */
1503 	cam_periph_release(periph);
1504 }
1505 
1506 static cam_status
1507 saregister(struct cam_periph *periph, void *arg)
1508 {
1509 	struct sa_softc *softc;
1510 	struct ccb_getdev *cgd;
1511 	struct ccb_pathinq cpi;
1512 	caddr_t match;
1513 	char tmpstr[80];
1514 	int i;
1515 
1516 	cgd = (struct ccb_getdev *)arg;
1517 	if (cgd == NULL) {
1518 		printf("saregister: no getdev CCB, can't register device\n");
1519 		return (CAM_REQ_CMP_ERR);
1520 	}
1521 
1522 	softc = (struct sa_softc *)
1523 	    malloc(sizeof (*softc), M_SCSISA, M_NOWAIT | M_ZERO);
1524 	if (softc == NULL) {
1525 		printf("saregister: Unable to probe new device. "
1526 		       "Unable to allocate softc\n");
1527 		return (CAM_REQ_CMP_ERR);
1528 	}
1529 	softc->scsi_rev = SID_ANSI_REV(&cgd->inq_data);
1530 	softc->state = SA_STATE_NORMAL;
1531 	softc->fileno = (daddr_t) -1;
1532 	softc->blkno = (daddr_t) -1;
1533 
1534 	bioq_init(&softc->bio_queue);
1535 	periph->softc = softc;
1536 
1537 	/*
1538 	 * See if this device has any quirks.
1539 	 */
1540 	match = cam_quirkmatch((caddr_t)&cgd->inq_data,
1541 			       (caddr_t)sa_quirk_table,
1542 			       sizeof(sa_quirk_table)/sizeof(*sa_quirk_table),
1543 			       sizeof(*sa_quirk_table), scsi_inquiry_match);
1544 
1545 	if (match != NULL) {
1546 		softc->quirks = ((struct sa_quirk_entry *)match)->quirks;
1547 		softc->last_media_blksize =
1548 		    ((struct sa_quirk_entry *)match)->prefblk;
1549 	} else
1550 		softc->quirks = SA_QUIRK_NONE;
1551 
1552 	bzero(&cpi, sizeof(cpi));
1553 	xpt_setup_ccb(&cpi.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
1554 	cpi.ccb_h.func_code = XPT_PATH_INQ;
1555 	xpt_action((union ccb *)&cpi);
1556 
1557 	/*
1558 	 * The SA driver supports a blocksize, but we don't know the
1559 	 * blocksize until we media is inserted.  So, set a flag to
1560 	 * indicate that the blocksize is unavailable right now.
1561 	 */
1562 	cam_periph_unlock(periph);
1563 	softc->device_stats = devstat_new_entry("sa", periph->unit_number, 0,
1564 	    DEVSTAT_BS_UNAVAILABLE, SID_TYPE(&cgd->inq_data) |
1565 	    XPORT_DEVSTAT_TYPE(cpi.transport), DEVSTAT_PRIORITY_TAPE);
1566 
1567 	/*
1568 	 * Load the default value that is either compiled in, or loaded
1569 	 * in the global kern.cam.sa.allow_io_split tunable.
1570 	 */
1571 	softc->allow_io_split = sa_allow_io_split;
1572 
1573 	/*
1574 	 * Load a per-instance tunable, if it exists.  NOTE that this
1575 	 * tunable WILL GO AWAY in FreeBSD 11.0.
1576 	 */
1577 	snprintf(tmpstr, sizeof(tmpstr), "kern.cam.sa.%u.allow_io_split",
1578 		 periph->unit_number);
1579 	TUNABLE_INT_FETCH(tmpstr, &softc->allow_io_split);
1580 
1581 	/*
1582 	 * If maxio isn't set, we fall back to DFLTPHYS.  Otherwise we take
1583 	 * the smaller of cpi.maxio or MAXPHYS.
1584 	 */
1585 	if (cpi.maxio == 0)
1586 		softc->maxio = DFLTPHYS;
1587 	else if (cpi.maxio > MAXPHYS)
1588 		softc->maxio = MAXPHYS;
1589 	else
1590 		softc->maxio = cpi.maxio;
1591 
1592 	/*
1593 	 * Record the controller's maximum I/O size so we can report it to
1594 	 * the user later.
1595 	 */
1596 	softc->cpi_maxio = cpi.maxio;
1597 
1598 	/*
1599 	 * By default we tell physio that we do not want our I/O split.
1600 	 * The user needs to have a 1:1 mapping between the size of his
1601 	 * write to a tape character device and the size of the write
1602 	 * that actually goes down to the drive.
1603 	 */
1604 	if (softc->allow_io_split == 0)
1605 		softc->si_flags = SI_NOSPLIT;
1606 	else
1607 		softc->si_flags = 0;
1608 
1609 	TASK_INIT(&softc->sysctl_task, 0, sasysctlinit, periph);
1610 
1611 	/*
1612 	 * If the SIM supports unmapped I/O, let physio know that we can
1613 	 * handle unmapped buffers.
1614 	 */
1615 	if (cpi.hba_misc & PIM_UNMAPPED)
1616 		softc->si_flags |= SI_UNMAPPED;
1617 
1618 	softc->devs.ctl_dev = make_dev(&sa_cdevsw, SAMINOR(SA_CTLDEV,
1619 	    0, SA_ATYPE_R), UID_ROOT, GID_OPERATOR,
1620 	    0660, "%s%d.ctl", periph->periph_name, periph->unit_number);
1621 	softc->devs.ctl_dev->si_drv1 = periph;
1622 	softc->devs.ctl_dev->si_iosize_max = softc->maxio;
1623 	softc->devs.ctl_dev->si_flags |= softc->si_flags;
1624 
1625 	for (i = 0; i < SA_NUM_MODES; i++) {
1626 
1627 		softc->devs.mode_devs[i].r_dev = make_dev(&sa_cdevsw,
1628 		    SAMINOR(SA_NOT_CTLDEV, i, SA_ATYPE_R),
1629 		    UID_ROOT, GID_OPERATOR, 0660, "%s%d.%d",
1630 		    periph->periph_name, periph->unit_number, i);
1631 		softc->devs.mode_devs[i].r_dev->si_drv1 = periph;
1632 		softc->devs.mode_devs[i].r_dev->si_iosize_max = softc->maxio;
1633 		softc->devs.mode_devs[i].r_dev->si_flags |= softc->si_flags;
1634 
1635 		softc->devs.mode_devs[i].nr_dev = make_dev(&sa_cdevsw,
1636 		    SAMINOR(SA_NOT_CTLDEV, i, SA_ATYPE_NR),
1637 		    UID_ROOT, GID_OPERATOR, 0660, "n%s%d.%d",
1638 		    periph->periph_name, periph->unit_number, i);
1639 		softc->devs.mode_devs[i].nr_dev->si_drv1 = periph;
1640 		softc->devs.mode_devs[i].nr_dev->si_iosize_max = softc->maxio;
1641 		softc->devs.mode_devs[i].nr_dev->si_flags |= softc->si_flags;
1642 
1643 		softc->devs.mode_devs[i].er_dev = make_dev(&sa_cdevsw,
1644 		    SAMINOR(SA_NOT_CTLDEV, i, SA_ATYPE_ER),
1645 		    UID_ROOT, GID_OPERATOR, 0660, "e%s%d.%d",
1646 		    periph->periph_name, periph->unit_number, i);
1647 		softc->devs.mode_devs[i].er_dev->si_drv1 = periph;
1648 		softc->devs.mode_devs[i].er_dev->si_iosize_max = softc->maxio;
1649 		softc->devs.mode_devs[i].er_dev->si_flags |= softc->si_flags;
1650 
1651 		/*
1652 		 * Make the (well known) aliases for the first mode.
1653 		 */
1654 		if (i == 0) {
1655 			struct cdev *alias;
1656 
1657 			alias = make_dev_alias(softc->devs.mode_devs[i].r_dev,
1658 			   "%s%d", periph->periph_name, periph->unit_number);
1659 			alias->si_drv1 = periph;
1660 			alias->si_iosize_max = softc->maxio;
1661 			alias->si_flags |= softc->si_flags;
1662 
1663 			alias = make_dev_alias(softc->devs.mode_devs[i].nr_dev,
1664 			    "n%s%d", periph->periph_name, periph->unit_number);
1665 			alias->si_drv1 = periph;
1666 			alias->si_iosize_max = softc->maxio;
1667 			alias->si_flags |= softc->si_flags;
1668 
1669 			alias = make_dev_alias(softc->devs.mode_devs[i].er_dev,
1670 			    "e%s%d", periph->periph_name, periph->unit_number);
1671 			alias->si_drv1 = periph;
1672 			alias->si_iosize_max = softc->maxio;
1673 			alias->si_flags |= softc->si_flags;
1674 		}
1675 	}
1676 	cam_periph_lock(periph);
1677 
1678 	/*
1679 	 * Bump the peripheral refcount for the sysctl thread, in case we
1680 	 * get invalidated before the thread has a chance to run.
1681 	 */
1682 	cam_periph_acquire(periph);
1683 	taskqueue_enqueue(taskqueue_thread, &softc->sysctl_task);
1684 
1685 	/*
1686 	 * Add an async callback so that we get
1687 	 * notified if this device goes away.
1688 	 */
1689 	xpt_register_async(AC_LOST_DEVICE, saasync, periph, periph->path);
1690 
1691 	xpt_announce_periph(periph, NULL);
1692 	xpt_announce_quirks(periph, softc->quirks, SA_QUIRK_BIT_STRING);
1693 
1694 	return (CAM_REQ_CMP);
1695 }
1696 
1697 static void
1698 sastart(struct cam_periph *periph, union ccb *start_ccb)
1699 {
1700 	struct sa_softc *softc;
1701 
1702 	softc = (struct sa_softc *)periph->softc;
1703 
1704 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sastart\n"));
1705 
1706 
1707 	switch (softc->state) {
1708 	case SA_STATE_NORMAL:
1709 	{
1710 		/* Pull a buffer from the queue and get going on it */
1711 		struct bio *bp;
1712 
1713 		/*
1714 		 * See if there is a buf with work for us to do..
1715 		 */
1716 		bp = bioq_first(&softc->bio_queue);
1717 		if (bp == NULL) {
1718 			xpt_release_ccb(start_ccb);
1719 		} else if ((softc->flags & SA_FLAG_ERR_PENDING) != 0) {
1720 			struct bio *done_bp;
1721 again:
1722 			softc->queue_count--;
1723 			bioq_remove(&softc->bio_queue, bp);
1724 			bp->bio_resid = bp->bio_bcount;
1725 			done_bp = bp;
1726 			if ((softc->flags & SA_FLAG_EOM_PENDING) != 0) {
1727 				/*
1728 				 * We now just clear errors in this case
1729 				 * and let the residual be the notifier.
1730 				 */
1731 				bp->bio_error = 0;
1732 			} else if ((softc->flags & SA_FLAG_EOF_PENDING) != 0) {
1733 				/*
1734 				 * This can only happen if we're reading
1735 				 * in fixed length mode. In this case,
1736 				 * we dump the rest of the list the
1737 				 * same way.
1738 				 */
1739 				bp->bio_error = 0;
1740 				if (bioq_first(&softc->bio_queue) != NULL) {
1741 					biodone(done_bp);
1742 					goto again;
1743 				}
1744 			} else if ((softc->flags & SA_FLAG_EIO_PENDING) != 0) {
1745 				bp->bio_error = EIO;
1746 				bp->bio_flags |= BIO_ERROR;
1747 			}
1748 			bp = bioq_first(&softc->bio_queue);
1749 			/*
1750 			 * Only if we have no other buffers queued up
1751 			 * do we clear the pending error flag.
1752 			 */
1753 			if (bp == NULL)
1754 				softc->flags &= ~SA_FLAG_ERR_PENDING;
1755 			CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
1756 			    ("sastart- ERR_PENDING now 0x%x, bp is %sNULL, "
1757 			    "%d more buffers queued up\n",
1758 			    (softc->flags & SA_FLAG_ERR_PENDING),
1759 			    (bp != NULL)? "not " : " ", softc->queue_count));
1760 			xpt_release_ccb(start_ccb);
1761 			biodone(done_bp);
1762 		} else {
1763 			u_int32_t length;
1764 
1765 			bioq_remove(&softc->bio_queue, bp);
1766 			softc->queue_count--;
1767 
1768 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
1769 				if (softc->blk_shift != 0) {
1770 					length =
1771 					    bp->bio_bcount >> softc->blk_shift;
1772 				} else if (softc->media_blksize != 0) {
1773 					length = bp->bio_bcount /
1774 					    softc->media_blksize;
1775 				} else {
1776 					bp->bio_error = EIO;
1777 					xpt_print(periph->path, "zero blocksize"
1778 					    " for FIXED length writes?\n");
1779 					biodone(bp);
1780 					break;
1781 				}
1782 #if	0
1783 				CAM_DEBUG(start_ccb->ccb_h.path, CAM_DEBUG_INFO,
1784 				    ("issuing a %d fixed record %s\n",
1785 				    length,  (bp->bio_cmd == BIO_READ)? "read" :
1786 				    "write"));
1787 #endif
1788 			} else {
1789 				length = bp->bio_bcount;
1790 #if	0
1791 				CAM_DEBUG(start_ccb->ccb_h.path, CAM_DEBUG_INFO,
1792 				    ("issuing a %d variable byte %s\n",
1793 				    length,  (bp->bio_cmd == BIO_READ)? "read" :
1794 				    "write"));
1795 #endif
1796 			}
1797 			devstat_start_transaction_bio(softc->device_stats, bp);
1798 			/*
1799 			 * Some people have theorized that we should
1800 			 * suppress illegal length indication if we are
1801 			 * running in variable block mode so that we don't
1802 			 * have to request sense every time our requested
1803 			 * block size is larger than the written block.
1804 			 * The residual information from the ccb allows
1805 			 * us to identify this situation anyway.  The only
1806 			 * problem with this is that we will not get
1807 			 * information about blocks that are larger than
1808 			 * our read buffer unless we set the block size
1809 			 * in the mode page to something other than 0.
1810 			 *
1811 			 * I believe that this is a non-issue. If user apps
1812 			 * don't adjust their read size to match our record
1813 			 * size, that's just life. Anyway, the typical usage
1814 			 * would be to issue, e.g., 64KB reads and occasionally
1815 			 * have to do deal with 512 byte or 1KB intermediate
1816 			 * records.
1817 			 */
1818 			softc->dsreg = (bp->bio_cmd == BIO_READ)?
1819 			    MTIO_DSREG_RD : MTIO_DSREG_WR;
1820 			scsi_sa_read_write(&start_ccb->csio, 0, sadone,
1821 			    MSG_SIMPLE_Q_TAG, (bp->bio_cmd == BIO_READ ?
1822 			    SCSI_RW_READ : SCSI_RW_WRITE) |
1823 			    ((bp->bio_flags & BIO_UNMAPPED) != 0 ?
1824 			    SCSI_RW_BIO : 0), FALSE,
1825 			    (softc->flags & SA_FLAG_FIXED) != 0, length,
1826 			    (bp->bio_flags & BIO_UNMAPPED) != 0 ? (void *)bp :
1827 			    bp->bio_data, bp->bio_bcount, SSD_FULL_SIZE,
1828 			    IO_TIMEOUT);
1829 			start_ccb->ccb_h.ccb_pflags &= ~SA_POSITION_UPDATED;
1830 			start_ccb->ccb_h.ccb_bp = bp;
1831 			bp = bioq_first(&softc->bio_queue);
1832 			xpt_action(start_ccb);
1833 		}
1834 
1835 		if (bp != NULL) {
1836 			/* Have more work to do, so ensure we stay scheduled */
1837 			xpt_schedule(periph, CAM_PRIORITY_NORMAL);
1838 		}
1839 		break;
1840 	}
1841 	case SA_STATE_ABNORMAL:
1842 	default:
1843 		panic("state 0x%x in sastart", softc->state);
1844 		break;
1845 	}
1846 }
1847 
1848 
1849 static void
1850 sadone(struct cam_periph *periph, union ccb *done_ccb)
1851 {
1852 	struct sa_softc *softc;
1853 	struct ccb_scsiio *csio;
1854 	struct bio *bp;
1855 	int error;
1856 
1857 	softc = (struct sa_softc *)periph->softc;
1858 	csio = &done_ccb->csio;
1859 
1860 	softc->dsreg = MTIO_DSREG_REST;
1861 	bp = (struct bio *)done_ccb->ccb_h.ccb_bp;
1862 	error = 0;
1863 	if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
1864 		if ((error = saerror(done_ccb, 0, 0)) == ERESTART) {
1865 			/*
1866 			 * A retry was scheduled, so just return.
1867 			 */
1868 			return;
1869 		}
1870 	}
1871 
1872 	if (error == EIO) {
1873 
1874 		/*
1875 		 * Catastrophic error. Mark the tape as frozen
1876 		 * (we no longer know tape position).
1877 		 *
1878 		 * Return all queued I/O with EIO, and unfreeze
1879 		 * our queue so that future transactions that
1880 		 * attempt to fix this problem can get to the
1881 		 * device.
1882 		 *
1883 		 */
1884 
1885 		softc->flags |= SA_FLAG_TAPE_FROZEN;
1886 		bioq_flush(&softc->bio_queue, NULL, EIO);
1887 	}
1888 	if (error != 0) {
1889 		bp->bio_resid = bp->bio_bcount;
1890 		bp->bio_error = error;
1891 		bp->bio_flags |= BIO_ERROR;
1892 		/*
1893 		 * In the error case, position is updated in saerror.
1894 		 */
1895 	} else {
1896 		bp->bio_resid = csio->resid;
1897 		bp->bio_error = 0;
1898 		if (csio->resid != 0) {
1899 			bp->bio_flags |= BIO_ERROR;
1900 		}
1901 		if (bp->bio_cmd == BIO_WRITE) {
1902 			softc->flags |= SA_FLAG_TAPE_WRITTEN;
1903 			softc->filemarks = 0;
1904 		}
1905 		if (!(csio->ccb_h.ccb_pflags & SA_POSITION_UPDATED) &&
1906 		    (softc->blkno != (daddr_t) -1)) {
1907 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
1908 				u_int32_t l;
1909 				if (softc->blk_shift != 0) {
1910 					l = bp->bio_bcount >>
1911 						softc->blk_shift;
1912 				} else {
1913 					l = bp->bio_bcount /
1914 						softc->media_blksize;
1915 				}
1916 				softc->blkno += (daddr_t) l;
1917 			} else {
1918 				softc->blkno++;
1919 			}
1920 		}
1921 	}
1922 	/*
1923 	 * If we had an error (immediate or pending),
1924 	 * release the device queue now.
1925 	 */
1926 	if (error || (softc->flags & SA_FLAG_ERR_PENDING))
1927 		cam_release_devq(done_ccb->ccb_h.path, 0, 0, 0, 0);
1928 	if (error || bp->bio_resid) {
1929 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
1930 		    	  ("error %d resid %ld count %ld\n", error,
1931 			  bp->bio_resid, bp->bio_bcount));
1932 	}
1933 	biofinish(bp, softc->device_stats, 0);
1934 	xpt_release_ccb(done_ccb);
1935 }
1936 
1937 /*
1938  * Mount the tape (make sure it's ready for I/O).
1939  */
1940 static int
1941 samount(struct cam_periph *periph, int oflags, struct cdev *dev)
1942 {
1943 	struct	sa_softc *softc;
1944 	union	ccb *ccb;
1945 	int	error;
1946 
1947 	/*
1948 	 * oflags can be checked for 'kind' of open (read-only check) - later
1949 	 * dev can be checked for a control-mode or compression open - later
1950 	 */
1951 	UNUSED_PARAMETER(oflags);
1952 	UNUSED_PARAMETER(dev);
1953 
1954 
1955 	softc = (struct sa_softc *)periph->softc;
1956 
1957 	/*
1958 	 * This should determine if something has happend since the last
1959 	 * open/mount that would invalidate the mount. We do *not* want
1960 	 * to retry this command- we just want the status. But we only
1961 	 * do this if we're mounted already- if we're not mounted,
1962 	 * we don't care about the unit read state and can instead use
1963 	 * this opportunity to attempt to reserve the tape unit.
1964 	 */
1965 
1966 	if (softc->flags & SA_FLAG_TAPE_MOUNTED) {
1967 		ccb = cam_periph_getccb(periph, 1);
1968 		scsi_test_unit_ready(&ccb->csio, 0, sadone,
1969 		    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, IO_TIMEOUT);
1970 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1971 		    softc->device_stats);
1972 		if (error == ENXIO) {
1973 			softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1974 			scsi_test_unit_ready(&ccb->csio, 0, sadone,
1975 			    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, IO_TIMEOUT);
1976 			error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1977 			    softc->device_stats);
1978 		} else if (error) {
1979 			/*
1980 			 * We don't need to freeze the tape because we
1981 			 * will now attempt to rewind/load it.
1982 			 */
1983 			softc->flags &= ~SA_FLAG_TAPE_MOUNTED;
1984 			if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
1985 				xpt_print(periph->path,
1986 				    "error %d on TUR in samount\n", error);
1987 			}
1988 		}
1989 	} else {
1990 		error = sareservereleaseunit(periph, TRUE);
1991 		if (error) {
1992 			return (error);
1993 		}
1994 		ccb = cam_periph_getccb(periph, 1);
1995 		scsi_test_unit_ready(&ccb->csio, 0, sadone,
1996 		    MSG_SIMPLE_Q_TAG, SSD_FULL_SIZE, IO_TIMEOUT);
1997 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
1998 		    softc->device_stats);
1999 	}
2000 
2001 	if ((softc->flags & SA_FLAG_TAPE_MOUNTED) == 0) {
2002 		struct scsi_read_block_limits_data *rblim = NULL;
2003 		int comp_enabled, comp_supported;
2004 		u_int8_t write_protect, guessing = 0;
2005 
2006 		/*
2007 		 * Clear out old state.
2008 		 */
2009 		softc->flags &= ~(SA_FLAG_TAPE_WP|SA_FLAG_TAPE_WRITTEN|
2010 				  SA_FLAG_ERR_PENDING|SA_FLAG_COMP_ENABLED|
2011 				  SA_FLAG_COMP_SUPP|SA_FLAG_COMP_UNSUPP);
2012 		softc->filemarks = 0;
2013 
2014 		/*
2015 		 * *Very* first off, make sure we're loaded to BOT.
2016 		 */
2017 		scsi_load_unload(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2018 		    FALSE, FALSE, 1, SSD_FULL_SIZE, REWIND_TIMEOUT);
2019 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2020 		    softc->device_stats);
2021 
2022 		/*
2023 		 * In case this doesn't work, do a REWIND instead
2024 		 */
2025 		if (error) {
2026 			scsi_rewind(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG,
2027 			    FALSE, SSD_FULL_SIZE, REWIND_TIMEOUT);
2028 			error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2029 				softc->device_stats);
2030 		}
2031 		if (error) {
2032 			xpt_release_ccb(ccb);
2033 			goto exit;
2034 		}
2035 
2036 		/*
2037 		 * Do a dummy test read to force access to the
2038 		 * media so that the drive will really know what's
2039 		 * there. We actually don't really care what the
2040 		 * blocksize on tape is and don't expect to really
2041 		 * read a full record.
2042 		 */
2043 		rblim = (struct  scsi_read_block_limits_data *)
2044 		    malloc(8192, M_SCSISA, M_NOWAIT);
2045 		if (rblim == NULL) {
2046 			xpt_print(periph->path, "no memory for test read\n");
2047 			xpt_release_ccb(ccb);
2048 			error = ENOMEM;
2049 			goto exit;
2050 		}
2051 
2052 		if ((softc->quirks & SA_QUIRK_NODREAD) == 0) {
2053 			scsi_sa_read_write(&ccb->csio, 0, sadone,
2054 			    MSG_SIMPLE_Q_TAG, 1, FALSE, 0, 8192,
2055 			    (void *) rblim, 8192, SSD_FULL_SIZE,
2056 			    IO_TIMEOUT);
2057 			(void) cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2058 			    softc->device_stats);
2059 			scsi_rewind(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
2060 			    FALSE, SSD_FULL_SIZE, REWIND_TIMEOUT);
2061 			error = cam_periph_runccb(ccb, saerror, CAM_RETRY_SELTO,
2062 			    SF_NO_PRINT | SF_RETRY_UA,
2063 			    softc->device_stats);
2064 			if (error) {
2065 				xpt_print(periph->path,
2066 				    "unable to rewind after test read\n");
2067 				xpt_release_ccb(ccb);
2068 				goto exit;
2069 			}
2070 		}
2071 
2072 		/*
2073 		 * Next off, determine block limits.
2074 		 */
2075 		scsi_read_block_limits(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG,
2076 		    rblim, SSD_FULL_SIZE, SCSIOP_TIMEOUT);
2077 
2078 		error = cam_periph_runccb(ccb, saerror, CAM_RETRY_SELTO,
2079 		    SF_NO_PRINT | SF_RETRY_UA, softc->device_stats);
2080 
2081 		xpt_release_ccb(ccb);
2082 
2083 		if (error != 0) {
2084 			/*
2085 			 * If it's less than SCSI-2, READ BLOCK LIMITS is not
2086 			 * a MANDATORY command. Anyway- it doesn't matter-
2087 			 * we can proceed anyway.
2088 			 */
2089 			softc->blk_gran = 0;
2090 			softc->max_blk = ~0;
2091 			softc->min_blk = 0;
2092 		} else {
2093 			if (softc->scsi_rev >= SCSI_REV_SPC) {
2094 				softc->blk_gran = RBL_GRAN(rblim);
2095 			} else {
2096 				softc->blk_gran = 0;
2097 			}
2098 			/*
2099 			 * We take max_blk == min_blk to mean a default to
2100 			 * fixed mode- but note that whatever we get out of
2101 			 * sagetparams below will actually determine whether
2102 			 * we are actually *in* fixed mode.
2103 			 */
2104 			softc->max_blk = scsi_3btoul(rblim->maximum);
2105 			softc->min_blk = scsi_2btoul(rblim->minimum);
2106 
2107 
2108 		}
2109 		/*
2110 		 * Next, perform a mode sense to determine
2111 		 * current density, blocksize, compression etc.
2112 		 */
2113 		error = sagetparams(periph, SA_PARAM_ALL,
2114 				    &softc->media_blksize,
2115 				    &softc->media_density,
2116 				    &softc->media_numblks,
2117 				    &softc->buffer_mode, &write_protect,
2118 				    &softc->speed, &comp_supported,
2119 				    &comp_enabled, &softc->comp_algorithm,
2120 				    NULL);
2121 
2122 		if (error != 0) {
2123 			/*
2124 			 * We could work a little harder here. We could
2125 			 * adjust our attempts to get information. It
2126 			 * might be an ancient tape drive. If someone
2127 			 * nudges us, we'll do that.
2128 			 */
2129 			goto exit;
2130 		}
2131 
2132 		/*
2133 		 * If no quirk has determined that this is a device that is
2134 		 * preferred to be in fixed or variable mode, now is the time
2135 		 * to find out.
2136 	 	 */
2137 		if ((softc->quirks & (SA_QUIRK_FIXED|SA_QUIRK_VARIABLE)) == 0) {
2138 			guessing = 1;
2139 			/*
2140 			 * This could be expensive to find out. Luckily we
2141 			 * only need to do this once. If we start out in
2142 			 * 'default' mode, try and set ourselves to one
2143 			 * of the densities that would determine a wad
2144 			 * of other stuff. Go from highest to lowest.
2145 			 */
2146 			if (softc->media_density == SCSI_DEFAULT_DENSITY) {
2147 				int i;
2148 				static u_int8_t ctry[] = {
2149 					SCSI_DENSITY_HALFINCH_PE,
2150 					SCSI_DENSITY_HALFINCH_6250C,
2151 					SCSI_DENSITY_HALFINCH_6250,
2152 					SCSI_DENSITY_HALFINCH_1600,
2153 					SCSI_DENSITY_HALFINCH_800,
2154 					SCSI_DENSITY_QIC_4GB,
2155 					SCSI_DENSITY_QIC_2GB,
2156 					SCSI_DENSITY_QIC_525_320,
2157 					SCSI_DENSITY_QIC_150,
2158 					SCSI_DENSITY_QIC_120,
2159 					SCSI_DENSITY_QIC_24,
2160 					SCSI_DENSITY_QIC_11_9TRK,
2161 					SCSI_DENSITY_QIC_11_4TRK,
2162 					SCSI_DENSITY_QIC_1320,
2163 					SCSI_DENSITY_QIC_3080,
2164 					0
2165 				};
2166 				for (i = 0; ctry[i]; i++) {
2167 					error = sasetparams(periph,
2168 					    SA_PARAM_DENSITY, 0, ctry[i],
2169 					    0, SF_NO_PRINT);
2170 					if (error == 0) {
2171 						softc->media_density = ctry[i];
2172 						break;
2173 					}
2174 				}
2175 			}
2176 			switch (softc->media_density) {
2177 			case SCSI_DENSITY_QIC_11_4TRK:
2178 			case SCSI_DENSITY_QIC_11_9TRK:
2179 			case SCSI_DENSITY_QIC_24:
2180 			case SCSI_DENSITY_QIC_120:
2181 			case SCSI_DENSITY_QIC_150:
2182 			case SCSI_DENSITY_QIC_525_320:
2183 			case SCSI_DENSITY_QIC_1320:
2184 			case SCSI_DENSITY_QIC_3080:
2185 				softc->quirks &= ~SA_QUIRK_2FM;
2186 				softc->quirks |= SA_QUIRK_FIXED|SA_QUIRK_1FM;
2187 				softc->last_media_blksize = 512;
2188 				break;
2189 			case SCSI_DENSITY_QIC_4GB:
2190 			case SCSI_DENSITY_QIC_2GB:
2191 				softc->quirks &= ~SA_QUIRK_2FM;
2192 				softc->quirks |= SA_QUIRK_FIXED|SA_QUIRK_1FM;
2193 				softc->last_media_blksize = 1024;
2194 				break;
2195 			default:
2196 				softc->last_media_blksize =
2197 				    softc->media_blksize;
2198 				softc->quirks |= SA_QUIRK_VARIABLE;
2199 				break;
2200 			}
2201 		}
2202 
2203 		/*
2204 		 * If no quirk has determined that this is a device that needs
2205 		 * to have 2 Filemarks at EOD, now is the time to find out.
2206 		 */
2207 
2208 		if ((softc->quirks & SA_QUIRK_2FM) == 0) {
2209 			switch (softc->media_density) {
2210 			case SCSI_DENSITY_HALFINCH_800:
2211 			case SCSI_DENSITY_HALFINCH_1600:
2212 			case SCSI_DENSITY_HALFINCH_6250:
2213 			case SCSI_DENSITY_HALFINCH_6250C:
2214 			case SCSI_DENSITY_HALFINCH_PE:
2215 				softc->quirks &= ~SA_QUIRK_1FM;
2216 				softc->quirks |= SA_QUIRK_2FM;
2217 				break;
2218 			default:
2219 				break;
2220 			}
2221 		}
2222 
2223 		/*
2224 		 * Now validate that some info we got makes sense.
2225 		 */
2226 		if ((softc->max_blk < softc->media_blksize) ||
2227 		    (softc->min_blk > softc->media_blksize &&
2228 		    softc->media_blksize)) {
2229 			xpt_print(periph->path,
2230 			    "BLOCK LIMITS (%d..%d) could not match current "
2231 			    "block settings (%d)- adjusting\n", softc->min_blk,
2232 			    softc->max_blk, softc->media_blksize);
2233 			softc->max_blk = softc->min_blk =
2234 			    softc->media_blksize;
2235 		}
2236 
2237 		/*
2238 		 * Now put ourselves into the right frame of mind based
2239 		 * upon quirks...
2240 		 */
2241 tryagain:
2242 		/*
2243 		 * If we want to be in FIXED mode and our current blocksize
2244 		 * is not equal to our last blocksize (if nonzero), try and
2245 		 * set ourselves to this last blocksize (as the 'preferred'
2246 		 * block size).  The initial quirkmatch at registry sets the
2247 		 * initial 'last' blocksize. If, for whatever reason, this
2248 		 * 'last' blocksize is zero, set the blocksize to 512,
2249 		 * or min_blk if that's larger.
2250 		 */
2251 		if ((softc->quirks & SA_QUIRK_FIXED) &&
2252 		    (softc->quirks & SA_QUIRK_NO_MODESEL) == 0 &&
2253 		    (softc->media_blksize != softc->last_media_blksize)) {
2254 			softc->media_blksize = softc->last_media_blksize;
2255 			if (softc->media_blksize == 0) {
2256 				softc->media_blksize = 512;
2257 				if (softc->media_blksize < softc->min_blk) {
2258 					softc->media_blksize = softc->min_blk;
2259 				}
2260 			}
2261 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE,
2262 			    softc->media_blksize, 0, 0, SF_NO_PRINT);
2263 			if (error) {
2264 				xpt_print(periph->path,
2265 				    "unable to set fixed blocksize to %d\n",
2266 				    softc->media_blksize);
2267 				goto exit;
2268 			}
2269 		}
2270 
2271 		if ((softc->quirks & SA_QUIRK_VARIABLE) &&
2272 		    (softc->media_blksize != 0)) {
2273 			softc->last_media_blksize = softc->media_blksize;
2274 			softc->media_blksize = 0;
2275 			error = sasetparams(periph, SA_PARAM_BLOCKSIZE,
2276 			    0, 0, 0, SF_NO_PRINT);
2277 			if (error) {
2278 				/*
2279 				 * If this fails and we were guessing, just
2280 				 * assume that we got it wrong and go try
2281 				 * fixed block mode. Don't even check against
2282 				 * density code at this point.
2283 				 */
2284 				if (guessing) {
2285 					softc->quirks &= ~SA_QUIRK_VARIABLE;
2286 					softc->quirks |= SA_QUIRK_FIXED;
2287 					if (softc->last_media_blksize == 0)
2288 						softc->last_media_blksize = 512;
2289 					goto tryagain;
2290 				}
2291 				xpt_print(periph->path,
2292 				    "unable to set variable blocksize\n");
2293 				goto exit;
2294 			}
2295 		}
2296 
2297 		/*
2298 		 * Now that we have the current block size,
2299 		 * set up some parameters for sastart's usage.
2300 		 */
2301 		if (softc->media_blksize) {
2302 			softc->flags |= SA_FLAG_FIXED;
2303 			if (powerof2(softc->media_blksize)) {
2304 				softc->blk_shift =
2305 				    ffs(softc->media_blksize) - 1;
2306 				softc->blk_mask = softc->media_blksize - 1;
2307 			} else {
2308 				softc->blk_mask = ~0;
2309 				softc->blk_shift = 0;
2310 			}
2311 		} else {
2312 			/*
2313 			 * The SCSI-3 spec allows 0 to mean "unspecified".
2314 			 * The SCSI-1 spec allows 0 to mean 'infinite'.
2315 			 *
2316 			 * Either works here.
2317 			 */
2318 			if (softc->max_blk == 0) {
2319 				softc->max_blk = ~0;
2320 			}
2321 			softc->blk_shift = 0;
2322 			if (softc->blk_gran != 0) {
2323 				softc->blk_mask = softc->blk_gran - 1;
2324 			} else {
2325 				softc->blk_mask = 0;
2326 			}
2327 		}
2328 
2329 		if (write_protect)
2330 			softc->flags |= SA_FLAG_TAPE_WP;
2331 
2332 		if (comp_supported) {
2333 			if (softc->saved_comp_algorithm == 0)
2334 				softc->saved_comp_algorithm =
2335 				    softc->comp_algorithm;
2336 			softc->flags |= SA_FLAG_COMP_SUPP;
2337 			if (comp_enabled)
2338 				softc->flags |= SA_FLAG_COMP_ENABLED;
2339 		} else
2340 			softc->flags |= SA_FLAG_COMP_UNSUPP;
2341 
2342 		if ((softc->buffer_mode == SMH_SA_BUF_MODE_NOBUF) &&
2343 		    (softc->quirks & SA_QUIRK_NO_MODESEL) == 0) {
2344 			error = sasetparams(periph, SA_PARAM_BUFF_MODE, 0,
2345 			    0, 0, SF_NO_PRINT);
2346 			if (error == 0) {
2347 				softc->buffer_mode = SMH_SA_BUF_MODE_SIBUF;
2348 			} else {
2349 				xpt_print(periph->path,
2350 				    "unable to set buffered mode\n");
2351 			}
2352 			error = 0;	/* not an error */
2353 		}
2354 
2355 
2356 		if (error == 0) {
2357 			softc->flags |= SA_FLAG_TAPE_MOUNTED;
2358 		}
2359 exit:
2360 		if (rblim != NULL)
2361 			free(rblim, M_SCSISA);
2362 
2363 		if (error != 0) {
2364 			softc->dsreg = MTIO_DSREG_NIL;
2365 		} else {
2366 			softc->fileno = softc->blkno = 0;
2367 			softc->dsreg = MTIO_DSREG_REST;
2368 		}
2369 #ifdef	SA_1FM_AT_EOD
2370 		if ((softc->quirks & SA_QUIRK_2FM) == 0)
2371 			softc->quirks |= SA_QUIRK_1FM;
2372 #else
2373 		if ((softc->quirks & SA_QUIRK_1FM) == 0)
2374 			softc->quirks |= SA_QUIRK_2FM;
2375 #endif
2376 	} else
2377 		xpt_release_ccb(ccb);
2378 
2379 	/*
2380 	 * If we return an error, we're not mounted any more,
2381 	 * so release any device reservation.
2382 	 */
2383 	if (error != 0) {
2384 		(void) sareservereleaseunit(periph, FALSE);
2385 	} else {
2386 		/*
2387 		 * Clear I/O residual.
2388 		 */
2389 		softc->last_io_resid = 0;
2390 		softc->last_ctl_resid = 0;
2391 	}
2392 	return (error);
2393 }
2394 
2395 /*
2396  * How many filemarks do we need to write if we were to terminate the
2397  * tape session right now? Note that this can be a negative number
2398  */
2399 
2400 static int
2401 samarkswanted(struct cam_periph *periph)
2402 {
2403 	int	markswanted;
2404 	struct	sa_softc *softc;
2405 
2406 	softc = (struct sa_softc *)periph->softc;
2407 	markswanted = 0;
2408 	if ((softc->flags & SA_FLAG_TAPE_WRITTEN) != 0) {
2409 		markswanted++;
2410 		if (softc->quirks & SA_QUIRK_2FM)
2411 			markswanted++;
2412 	}
2413 	markswanted -= softc->filemarks;
2414 	return (markswanted);
2415 }
2416 
2417 static int
2418 sacheckeod(struct cam_periph *periph)
2419 {
2420 	int	error;
2421 	int	markswanted;
2422 
2423 	markswanted = samarkswanted(periph);
2424 
2425 	if (markswanted > 0) {
2426 		error = sawritefilemarks(periph, markswanted, FALSE);
2427 	} else {
2428 		error = 0;
2429 	}
2430 	return (error);
2431 }
2432 
2433 static int
2434 saerror(union ccb *ccb, u_int32_t cflgs, u_int32_t sflgs)
2435 {
2436 	static const char *toobig =
2437 	    "%d-byte tape record bigger than supplied buffer\n";
2438 	struct	cam_periph *periph;
2439 	struct	sa_softc *softc;
2440 	struct	ccb_scsiio *csio;
2441 	struct	scsi_sense_data *sense;
2442 	uint64_t resid = 0;
2443 	int64_t	info = 0;
2444 	cam_status status;
2445 	int error_code, sense_key, asc, ascq, error, aqvalid, stream_valid;
2446 	int sense_len;
2447 	uint8_t stream_bits;
2448 
2449 	periph = xpt_path_periph(ccb->ccb_h.path);
2450 	softc = (struct sa_softc *)periph->softc;
2451 	csio = &ccb->csio;
2452 	sense = &csio->sense_data;
2453 	sense_len = csio->sense_len - csio->sense_resid;
2454 	scsi_extract_sense_len(sense, sense_len, &error_code, &sense_key,
2455 	    &asc, &ascq, /*show_errors*/ 1);
2456 	if (asc != -1 && ascq != -1)
2457 		aqvalid = 1;
2458 	else
2459 		aqvalid = 0;
2460 	if (scsi_get_stream_info(sense, sense_len, NULL, &stream_bits) == 0)
2461 		stream_valid = 1;
2462 	else
2463 		stream_valid = 0;
2464 	error = 0;
2465 
2466 	status = csio->ccb_h.status & CAM_STATUS_MASK;
2467 
2468 	/*
2469 	 * Calculate/latch up, any residuals... We do this in a funny 2-step
2470 	 * so we can print stuff here if we have CAM_DEBUG enabled for this
2471 	 * unit.
2472 	 */
2473 	if (status == CAM_SCSI_STATUS_ERROR) {
2474 		if (scsi_get_sense_info(sense, sense_len, SSD_DESC_INFO, &resid,
2475 					&info) == 0) {
2476 			if ((softc->flags & SA_FLAG_FIXED) != 0)
2477 				resid *= softc->media_blksize;
2478 		} else {
2479 			resid = csio->dxfer_len;
2480 			info = resid;
2481 			if ((softc->flags & SA_FLAG_FIXED) != 0) {
2482 				if (softc->media_blksize)
2483 					info /= softc->media_blksize;
2484 			}
2485 		}
2486 		if (csio->cdb_io.cdb_bytes[0] == SA_READ ||
2487 		    csio->cdb_io.cdb_bytes[0] == SA_WRITE) {
2488 			bcopy((caddr_t) sense, (caddr_t) &softc->last_io_sense,
2489 			    sizeof (struct scsi_sense_data));
2490 			bcopy(csio->cdb_io.cdb_bytes, softc->last_io_cdb,
2491 			    (int) csio->cdb_len);
2492 			softc->last_io_resid = resid;
2493 			softc->last_resid_was_io = 1;
2494 		} else {
2495 			bcopy((caddr_t) sense, (caddr_t) &softc->last_ctl_sense,
2496 			    sizeof (struct scsi_sense_data));
2497 			bcopy(csio->cdb_io.cdb_bytes, softc->last_ctl_cdb,
2498 			    (int) csio->cdb_len);
2499 			softc->last_ctl_resid = resid;
2500 			softc->last_resid_was_io = 0;
2501 		}
2502 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO, ("CDB[0]=0x%x Key 0x%x "
2503 		    "ASC/ASCQ 0x%x/0x%x CAM STATUS 0x%x flags 0x%x resid %jd "
2504 		    "dxfer_len %d\n", csio->cdb_io.cdb_bytes[0] & 0xff,
2505 		    sense_key, asc, ascq, status,
2506 		    (stream_valid) ? stream_bits : 0, (intmax_t)resid,
2507 		    csio->dxfer_len));
2508 	} else {
2509 		CAM_DEBUG(periph->path, CAM_DEBUG_INFO,
2510 		    ("Cam Status 0x%x\n", status));
2511 	}
2512 
2513 	switch (status) {
2514 	case CAM_REQ_CMP:
2515 		return (0);
2516 	case CAM_SCSI_STATUS_ERROR:
2517 		/*
2518 		 * If a read/write command, we handle it here.
2519 		 */
2520 		if (csio->cdb_io.cdb_bytes[0] == SA_READ ||
2521 		    csio->cdb_io.cdb_bytes[0] == SA_WRITE) {
2522 			break;
2523 		}
2524 		/*
2525 		 * If this was just EOM/EOP, Filemark, Setmark or ILI detected
2526 		 * on a non read/write command, we assume it's not an error
2527 		 * and propagate the residule and return.
2528 		 */
2529 		if ((aqvalid && asc == 0 && ascq > 0 && ascq <= 5) ||
2530 		    (aqvalid == 0 && sense_key == SSD_KEY_NO_SENSE)) {
2531 			csio->resid = resid;
2532 			QFRLS(ccb);
2533 			return (0);
2534 		}
2535 		/*
2536 		 * Otherwise, we let the common code handle this.
2537 		 */
2538 		return (cam_periph_error(ccb, cflgs, sflgs, &softc->saved_ccb));
2539 
2540 	/*
2541 	 * XXX: To Be Fixed
2542 	 * We cannot depend upon CAM honoring retry counts for these.
2543 	 */
2544 	case CAM_SCSI_BUS_RESET:
2545 	case CAM_BDR_SENT:
2546 		if (ccb->ccb_h.retry_count <= 0) {
2547 			return (EIO);
2548 		}
2549 		/* FALLTHROUGH */
2550 	default:
2551 		return (cam_periph_error(ccb, cflgs, sflgs, &softc->saved_ccb));
2552 	}
2553 
2554 	/*
2555 	 * Handle filemark, end of tape, mismatched record sizes....
2556 	 * From this point out, we're only handling read/write cases.
2557 	 * Handle writes && reads differently.
2558 	 */
2559 
2560 	if (csio->cdb_io.cdb_bytes[0] == SA_WRITE) {
2561 		if (sense_key == SSD_KEY_VOLUME_OVERFLOW) {
2562 			csio->resid = resid;
2563 			error = ENOSPC;
2564 		} else if ((stream_valid != 0) && (stream_bits & SSD_EOM)) {
2565 			softc->flags |= SA_FLAG_EOM_PENDING;
2566 			/*
2567 			 * Grotesque as it seems, the few times
2568 			 * I've actually seen a non-zero resid,
2569 			 * the tape drive actually lied and had
2570 			 * written all the data!.
2571 			 */
2572 			csio->resid = 0;
2573 		}
2574 	} else {
2575 		csio->resid = resid;
2576 		if (sense_key == SSD_KEY_BLANK_CHECK) {
2577 			if (softc->quirks & SA_QUIRK_1FM) {
2578 				error = 0;
2579 				softc->flags |= SA_FLAG_EOM_PENDING;
2580 			} else {
2581 				error = EIO;
2582 			}
2583 		} else if ((stream_valid != 0) && (stream_bits & SSD_FILEMARK)){
2584 			if (softc->flags & SA_FLAG_FIXED) {
2585 				error = -1;
2586 				softc->flags |= SA_FLAG_EOF_PENDING;
2587 			}
2588 			/*
2589 			 * Unconditionally, if we detected a filemark on a read,
2590 			 * mark that we've run moved a file ahead.
2591 			 */
2592 			if (softc->fileno != (daddr_t) -1) {
2593 				softc->fileno++;
2594 				softc->blkno = 0;
2595 				csio->ccb_h.ccb_pflags |= SA_POSITION_UPDATED;
2596 			}
2597 		}
2598 	}
2599 
2600 	/*
2601 	 * Incorrect Length usually applies to read, but can apply to writes.
2602 	 */
2603 	if (error == 0 && (stream_valid != 0) && (stream_bits & SSD_ILI)) {
2604 		if (info < 0) {
2605 			xpt_print(csio->ccb_h.path, toobig,
2606 			    csio->dxfer_len - info);
2607 			csio->resid = csio->dxfer_len;
2608 			error = EIO;
2609 		} else {
2610 			csio->resid = resid;
2611 			if (softc->flags & SA_FLAG_FIXED) {
2612 				softc->flags |= SA_FLAG_EIO_PENDING;
2613 			}
2614 			/*
2615 			 * Bump the block number if we hadn't seen a filemark.
2616 			 * Do this independent of errors (we've moved anyway).
2617 			 */
2618 			if ((stream_valid == 0) ||
2619 			    (stream_bits & SSD_FILEMARK) == 0) {
2620 				if (softc->blkno != (daddr_t) -1) {
2621 					softc->blkno++;
2622 					csio->ccb_h.ccb_pflags |=
2623 					   SA_POSITION_UPDATED;
2624 				}
2625 			}
2626 		}
2627 	}
2628 
2629 	if (error <= 0) {
2630 		/*
2631 		 * Unfreeze the queue if frozen as we're not returning anything
2632 		 * to our waiters that would indicate an I/O error has occurred
2633 		 * (yet).
2634 		 */
2635 		QFRLS(ccb);
2636 		error = 0;
2637 	}
2638 	return (error);
2639 }
2640 
2641 static int
2642 sagetparams(struct cam_periph *periph, sa_params params_to_get,
2643 	    u_int32_t *blocksize, u_int8_t *density, u_int32_t *numblocks,
2644 	    int *buff_mode, u_int8_t *write_protect, u_int8_t *speed,
2645 	    int *comp_supported, int *comp_enabled, u_int32_t *comp_algorithm,
2646 	    sa_comp_t *tcs)
2647 {
2648 	union ccb *ccb;
2649 	void *mode_buffer;
2650 	struct scsi_mode_header_6 *mode_hdr;
2651 	struct scsi_mode_blk_desc *mode_blk;
2652 	int mode_buffer_len;
2653 	struct sa_softc *softc;
2654 	u_int8_t cpage;
2655 	int error;
2656 	cam_status status;
2657 
2658 	softc = (struct sa_softc *)periph->softc;
2659 	ccb = cam_periph_getccb(periph, 1);
2660 	if (softc->quirks & SA_QUIRK_NO_CPAGE)
2661 		cpage = SA_DEVICE_CONFIGURATION_PAGE;
2662 	else
2663 		cpage = SA_DATA_COMPRESSION_PAGE;
2664 
2665 retry:
2666 	mode_buffer_len = sizeof(*mode_hdr) + sizeof(*mode_blk);
2667 
2668 	if (params_to_get & SA_PARAM_COMPRESSION) {
2669 		if (softc->quirks & SA_QUIRK_NOCOMP) {
2670 			*comp_supported = FALSE;
2671 			params_to_get &= ~SA_PARAM_COMPRESSION;
2672 		} else
2673 			mode_buffer_len += sizeof (sa_comp_t);
2674 	}
2675 
2676 	/* XXX Fix M_NOWAIT */
2677 	mode_buffer = malloc(mode_buffer_len, M_SCSISA, M_NOWAIT | M_ZERO);
2678 	if (mode_buffer == NULL) {
2679 		xpt_release_ccb(ccb);
2680 		return (ENOMEM);
2681 	}
2682 	mode_hdr = (struct scsi_mode_header_6 *)mode_buffer;
2683 	mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
2684 
2685 	/* it is safe to retry this */
2686 	scsi_mode_sense(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2687 	    SMS_PAGE_CTRL_CURRENT, (params_to_get & SA_PARAM_COMPRESSION) ?
2688 	    cpage : SMS_VENDOR_SPECIFIC_PAGE, mode_buffer, mode_buffer_len,
2689 	    SSD_FULL_SIZE, SCSIOP_TIMEOUT);
2690 
2691 	error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2692 	    softc->device_stats);
2693 
2694 	status = ccb->ccb_h.status & CAM_STATUS_MASK;
2695 
2696 	if (error == EINVAL && (params_to_get & SA_PARAM_COMPRESSION) != 0) {
2697 		/*
2698 		 * Hmm. Let's see if we can try another page...
2699 		 * If we've already done that, give up on compression
2700 		 * for this device and remember this for the future
2701 		 * and attempt the request without asking for compression
2702 		 * info.
2703 		 */
2704 		if (cpage == SA_DATA_COMPRESSION_PAGE) {
2705 			cpage = SA_DEVICE_CONFIGURATION_PAGE;
2706 			goto retry;
2707 		}
2708 		softc->quirks |= SA_QUIRK_NOCOMP;
2709 		free(mode_buffer, M_SCSISA);
2710 		goto retry;
2711 	} else if (status == CAM_SCSI_STATUS_ERROR) {
2712 		/* Tell the user about the fatal error. */
2713 		scsi_sense_print(&ccb->csio);
2714 		goto sagetparamsexit;
2715 	}
2716 
2717 	/*
2718 	 * If the user only wants the compression information, and
2719 	 * the device doesn't send back the block descriptor, it's
2720 	 * no big deal.  If the user wants more than just
2721 	 * compression, though, and the device doesn't pass back the
2722 	 * block descriptor, we need to send another mode sense to
2723 	 * get the block descriptor.
2724 	 */
2725 	if ((mode_hdr->blk_desc_len == 0) &&
2726 	    (params_to_get & SA_PARAM_COMPRESSION) &&
2727 	    (params_to_get & ~(SA_PARAM_COMPRESSION))) {
2728 
2729 		/*
2730 		 * Decrease the mode buffer length by the size of
2731 		 * the compression page, to make sure the data
2732 		 * there doesn't get overwritten.
2733 		 */
2734 		mode_buffer_len -= sizeof (sa_comp_t);
2735 
2736 		/*
2737 		 * Now move the compression page that we presumably
2738 		 * got back down the memory chunk a little bit so
2739 		 * it doesn't get spammed.
2740 		 */
2741 		bcopy(&mode_hdr[0], &mode_hdr[1], sizeof (sa_comp_t));
2742 		bzero(&mode_hdr[0], sizeof (mode_hdr[0]));
2743 
2744 		/*
2745 		 * Now, we issue another mode sense and just ask
2746 		 * for the block descriptor, etc.
2747 		 */
2748 
2749 		scsi_mode_sense(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
2750 		    SMS_PAGE_CTRL_CURRENT, SMS_VENDOR_SPECIFIC_PAGE,
2751 		    mode_buffer, mode_buffer_len, SSD_FULL_SIZE,
2752 		    SCSIOP_TIMEOUT);
2753 
2754 		error = cam_periph_runccb(ccb, saerror, 0, SF_NO_PRINT,
2755 		    softc->device_stats);
2756 
2757 		if (error != 0)
2758 			goto sagetparamsexit;
2759 	}
2760 
2761 	if (params_to_get & SA_PARAM_BLOCKSIZE)
2762 		*blocksize = scsi_3btoul(mode_blk->blklen);
2763 
2764 	if (params_to_get & SA_PARAM_NUMBLOCKS)
2765 		*numblocks = scsi_3btoul(mode_blk->nblocks);
2766 
2767 	if (params_to_get & SA_PARAM_BUFF_MODE)
2768 		*buff_mode = mode_hdr->dev_spec & SMH_SA_BUF_MODE_MASK;
2769 
2770 	if (params_to_get & SA_PARAM_DENSITY)
2771 		*density = mode_blk->density;
2772 
2773 	if (params_to_get & SA_PARAM_WP)
2774 		*write_protect = (mode_hdr->dev_spec & SMH_SA_WP)? TRUE : FALSE;
2775 
2776 	if (params_to_get & SA_PARAM_SPEED)
2777 		*speed = mode_hdr->dev_spec & SMH_SA_SPEED_MASK;
2778 
2779 	if (params_to_get & SA_PARAM_COMPRESSION) {
2780 		sa_comp_t *ntcs = (sa_comp_t *) &mode_blk[1];
2781 		if (cpage == SA_DATA_COMPRESSION_PAGE) {
2782 			struct scsi_data_compression_page *cp = &ntcs->dcomp;
2783 			*comp_supported =
2784 			    (cp->dce_and_dcc & SA_DCP_DCC)? TRUE : FALSE;
2785 			*comp_enabled =
2786 			    (cp->dce_and_dcc & SA_DCP_DCE)? TRUE : FALSE;
2787 			*comp_algorithm = scsi_4btoul(cp->comp_algorithm);
2788 		} else {
2789 			struct scsi_dev_conf_page *cp = &ntcs->dconf;
2790 			/*
2791 			 * We don't really know whether this device supports
2792 			 * Data Compression if the algorithm field is
2793 			 * zero. Just say we do.
2794 			 */
2795 			*comp_supported = TRUE;
2796 			*comp_enabled =
2797 			    (cp->sel_comp_alg != SA_COMP_NONE)? TRUE : FALSE;
2798 			*comp_algorithm = cp->sel_comp_alg;
2799 		}
2800 		if (tcs != NULL)
2801 			bcopy(ntcs, tcs, sizeof (sa_comp_t));
2802 	}
2803 
2804 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
2805 		int idx;
2806 		char *xyz = mode_buffer;
2807 		xpt_print_path(periph->path);
2808 		printf("Mode Sense Data=");
2809 		for (idx = 0; idx < mode_buffer_len; idx++)
2810 			printf(" 0x%02x", xyz[idx] & 0xff);
2811 		printf("\n");
2812 	}
2813 
2814 sagetparamsexit:
2815 
2816 	xpt_release_ccb(ccb);
2817 	free(mode_buffer, M_SCSISA);
2818 	return (error);
2819 }
2820 
2821 /*
2822  * The purpose of this function is to set one of four different parameters
2823  * for a tape drive:
2824  *	- blocksize
2825  *	- density
2826  *	- compression / compression algorithm
2827  *	- buffering mode
2828  *
2829  * The assumption is that this will be called from saioctl(), and therefore
2830  * from a process context.  Thus the waiting malloc calls below.  If that
2831  * assumption ever changes, the malloc calls should be changed to be
2832  * NOWAIT mallocs.
2833  *
2834  * Any or all of the four parameters may be set when this function is
2835  * called.  It should handle setting more than one parameter at once.
2836  */
2837 static int
2838 sasetparams(struct cam_periph *periph, sa_params params_to_set,
2839 	    u_int32_t blocksize, u_int8_t density, u_int32_t calg,
2840 	    u_int32_t sense_flags)
2841 {
2842 	struct sa_softc *softc;
2843 	u_int32_t current_blocksize;
2844 	u_int32_t current_calg;
2845 	u_int8_t current_density;
2846 	u_int8_t current_speed;
2847 	int comp_enabled, comp_supported;
2848 	void *mode_buffer;
2849 	int mode_buffer_len;
2850 	struct scsi_mode_header_6 *mode_hdr;
2851 	struct scsi_mode_blk_desc *mode_blk;
2852 	sa_comp_t *ccomp, *cpage;
2853 	int buff_mode;
2854 	union ccb *ccb = NULL;
2855 	int error;
2856 
2857 	softc = (struct sa_softc *)periph->softc;
2858 
2859 	ccomp = malloc(sizeof (sa_comp_t), M_SCSISA, M_NOWAIT);
2860 	if (ccomp == NULL)
2861 		return (ENOMEM);
2862 
2863 	/*
2864 	 * Since it doesn't make sense to set the number of blocks, or
2865 	 * write protection, we won't try to get the current value.  We
2866 	 * always want to get the blocksize, so we can set it back to the
2867 	 * proper value.
2868 	 */
2869 	error = sagetparams(periph,
2870 	    params_to_set | SA_PARAM_BLOCKSIZE | SA_PARAM_SPEED,
2871 	    &current_blocksize, &current_density, NULL, &buff_mode, NULL,
2872 	    &current_speed, &comp_supported, &comp_enabled,
2873 	    &current_calg, ccomp);
2874 
2875 	if (error != 0) {
2876 		free(ccomp, M_SCSISA);
2877 		return (error);
2878 	}
2879 
2880 	mode_buffer_len = sizeof(*mode_hdr) + sizeof(*mode_blk);
2881 	if (params_to_set & SA_PARAM_COMPRESSION)
2882 		mode_buffer_len += sizeof (sa_comp_t);
2883 
2884 	mode_buffer = malloc(mode_buffer_len, M_SCSISA, M_NOWAIT | M_ZERO);
2885 	if (mode_buffer == NULL) {
2886 		free(ccomp, M_SCSISA);
2887 		return (ENOMEM);
2888 	}
2889 
2890 	mode_hdr = (struct scsi_mode_header_6 *)mode_buffer;
2891 	mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
2892 
2893 	ccb = cam_periph_getccb(periph, 1);
2894 
2895 retry:
2896 
2897 	if (params_to_set & SA_PARAM_COMPRESSION) {
2898 		if (mode_blk) {
2899 			cpage = (sa_comp_t *)&mode_blk[1];
2900 		} else {
2901 			cpage = (sa_comp_t *)&mode_hdr[1];
2902 		}
2903 		bcopy(ccomp, cpage, sizeof (sa_comp_t));
2904 		cpage->hdr.pagecode &= ~0x80;
2905 	} else
2906 		cpage = NULL;
2907 
2908 	/*
2909 	 * If the caller wants us to set the blocksize, use the one they
2910 	 * pass in.  Otherwise, use the blocksize we got back from the
2911 	 * mode select above.
2912 	 */
2913 	if (mode_blk) {
2914 		if (params_to_set & SA_PARAM_BLOCKSIZE)
2915 			scsi_ulto3b(blocksize, mode_blk->blklen);
2916 		else
2917 			scsi_ulto3b(current_blocksize, mode_blk->blklen);
2918 
2919 		/*
2920 		 * Set density if requested, else preserve old density.
2921 		 * SCSI_SAME_DENSITY only applies to SCSI-2 or better
2922 		 * devices, else density we've latched up in our softc.
2923 		 */
2924 		if (params_to_set & SA_PARAM_DENSITY) {
2925 			mode_blk->density = density;
2926 		} else if (softc->scsi_rev > SCSI_REV_CCS) {
2927 			mode_blk->density = SCSI_SAME_DENSITY;
2928 		} else {
2929 			mode_blk->density = softc->media_density;
2930 		}
2931 	}
2932 
2933 	/*
2934 	 * For mode selects, these two fields must be zero.
2935 	 */
2936 	mode_hdr->data_length = 0;
2937 	mode_hdr->medium_type = 0;
2938 
2939 	/* set the speed to the current value */
2940 	mode_hdr->dev_spec = current_speed;
2941 
2942 	/* if set, set single-initiator buffering mode */
2943 	if (softc->buffer_mode == SMH_SA_BUF_MODE_SIBUF) {
2944 		mode_hdr->dev_spec |= SMH_SA_BUF_MODE_SIBUF;
2945 	}
2946 
2947 	if (mode_blk)
2948 		mode_hdr->blk_desc_len = sizeof(struct scsi_mode_blk_desc);
2949 	else
2950 		mode_hdr->blk_desc_len = 0;
2951 
2952 	/*
2953 	 * First, if the user wants us to set the compression algorithm or
2954 	 * just turn compression on, check to make sure that this drive
2955 	 * supports compression.
2956 	 */
2957 	if (params_to_set & SA_PARAM_COMPRESSION) {
2958 		/*
2959 		 * If the compression algorithm is 0, disable compression.
2960 		 * If the compression algorithm is non-zero, enable
2961 		 * compression and set the compression type to the
2962 		 * specified compression algorithm, unless the algorithm is
2963 		 * MT_COMP_ENABLE.  In that case, we look at the
2964 		 * compression algorithm that is currently set and if it is
2965 		 * non-zero, we leave it as-is.  If it is zero, and we have
2966 		 * saved a compression algorithm from a time when
2967 		 * compression was enabled before, set the compression to
2968 		 * the saved value.
2969 		 */
2970 		switch (ccomp->hdr.pagecode & ~0x80) {
2971 		case SA_DEVICE_CONFIGURATION_PAGE:
2972 		{
2973 			struct scsi_dev_conf_page *dcp = &cpage->dconf;
2974 			if (calg == 0) {
2975 				dcp->sel_comp_alg = SA_COMP_NONE;
2976 				break;
2977 			}
2978 			if (calg != MT_COMP_ENABLE) {
2979 				dcp->sel_comp_alg = calg;
2980 			} else if (dcp->sel_comp_alg == SA_COMP_NONE &&
2981 			    softc->saved_comp_algorithm != 0) {
2982 				dcp->sel_comp_alg = softc->saved_comp_algorithm;
2983 			}
2984 			break;
2985 		}
2986 		case SA_DATA_COMPRESSION_PAGE:
2987 		if (ccomp->dcomp.dce_and_dcc & SA_DCP_DCC) {
2988 			struct scsi_data_compression_page *dcp = &cpage->dcomp;
2989 			if (calg == 0) {
2990 				/*
2991 				 * Disable compression, but leave the
2992 				 * decompression and the capability bit
2993 				 * alone.
2994 				 */
2995 				dcp->dce_and_dcc = SA_DCP_DCC;
2996 				dcp->dde_and_red |= SA_DCP_DDE;
2997 				break;
2998 			}
2999 			/* enable compression && decompression */
3000 			dcp->dce_and_dcc = SA_DCP_DCE | SA_DCP_DCC;
3001 			dcp->dde_and_red |= SA_DCP_DDE;
3002 			/*
3003 			 * If there, use compression algorithm from caller.
3004 			 * Otherwise, if there's a saved compression algorithm
3005 			 * and there is no current algorithm, use the saved
3006 			 * algorithm. Else parrot back what we got and hope
3007 			 * for the best.
3008 			 */
3009 			if (calg != MT_COMP_ENABLE) {
3010 				scsi_ulto4b(calg, dcp->comp_algorithm);
3011 				scsi_ulto4b(calg, dcp->decomp_algorithm);
3012 			} else if (scsi_4btoul(dcp->comp_algorithm) == 0 &&
3013 			    softc->saved_comp_algorithm != 0) {
3014 				scsi_ulto4b(softc->saved_comp_algorithm,
3015 				    dcp->comp_algorithm);
3016 				scsi_ulto4b(softc->saved_comp_algorithm,
3017 				    dcp->decomp_algorithm);
3018 			}
3019 			break;
3020 		}
3021 		/*
3022 		 * Compression does not appear to be supported-
3023 		 * at least via the DATA COMPRESSION page. It
3024 		 * would be too much to ask us to believe that
3025 		 * the page itself is supported, but incorrectly
3026 		 * reports an ability to manipulate data compression,
3027 		 * so we'll assume that this device doesn't support
3028 		 * compression. We can just fall through for that.
3029 		 */
3030 		/* FALLTHROUGH */
3031 		default:
3032 			/*
3033 			 * The drive doesn't seem to support compression,
3034 			 * so turn off the set compression bit.
3035 			 */
3036 			params_to_set &= ~SA_PARAM_COMPRESSION;
3037 			xpt_print(periph->path,
3038 			    "device does not seem to support compression\n");
3039 
3040 			/*
3041 			 * If that was the only thing the user wanted us to set,
3042 			 * clean up allocated resources and return with
3043 			 * 'operation not supported'.
3044 			 */
3045 			if (params_to_set == SA_PARAM_NONE) {
3046 				free(mode_buffer, M_SCSISA);
3047 				xpt_release_ccb(ccb);
3048 				return (ENODEV);
3049 			}
3050 
3051 			/*
3052 			 * That wasn't the only thing the user wanted us to set.
3053 			 * So, decrease the stated mode buffer length by the
3054 			 * size of the compression mode page.
3055 			 */
3056 			mode_buffer_len -= sizeof(sa_comp_t);
3057 		}
3058 	}
3059 
3060 	/* It is safe to retry this operation */
3061 	scsi_mode_select(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG,
3062 	    (params_to_set & SA_PARAM_COMPRESSION)? TRUE : FALSE,
3063 	    FALSE, mode_buffer, mode_buffer_len, SSD_FULL_SIZE, SCSIOP_TIMEOUT);
3064 
3065 	error = cam_periph_runccb(ccb, saerror, 0,
3066 	    sense_flags, softc->device_stats);
3067 
3068 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
3069 		int idx;
3070 		char *xyz = mode_buffer;
3071 		xpt_print_path(periph->path);
3072 		printf("Err%d, Mode Select Data=", error);
3073 		for (idx = 0; idx < mode_buffer_len; idx++)
3074 			printf(" 0x%02x", xyz[idx] & 0xff);
3075 		printf("\n");
3076 	}
3077 
3078 
3079 	if (error) {
3080 		/*
3081 		 * If we can, try without setting density/blocksize.
3082 		 */
3083 		if (mode_blk) {
3084 			if ((params_to_set &
3085 			    (SA_PARAM_DENSITY|SA_PARAM_BLOCKSIZE)) == 0) {
3086 				mode_blk = NULL;
3087 				goto retry;
3088 			}
3089 		} else {
3090 			mode_blk = (struct scsi_mode_blk_desc *)&mode_hdr[1];
3091 			cpage = (sa_comp_t *)&mode_blk[1];
3092 		}
3093 
3094 		/*
3095 		 * If we were setting the blocksize, and that failed, we
3096 		 * want to set it to its original value.  If we weren't
3097 		 * setting the blocksize, we don't want to change it.
3098 		 */
3099 		scsi_ulto3b(current_blocksize, mode_blk->blklen);
3100 
3101 		/*
3102 		 * Set density if requested, else preserve old density.
3103 		 * SCSI_SAME_DENSITY only applies to SCSI-2 or better
3104 		 * devices, else density we've latched up in our softc.
3105 		 */
3106 		if (params_to_set & SA_PARAM_DENSITY) {
3107 			mode_blk->density = current_density;
3108 		} else if (softc->scsi_rev > SCSI_REV_CCS) {
3109 			mode_blk->density = SCSI_SAME_DENSITY;
3110 		} else {
3111 			mode_blk->density = softc->media_density;
3112 		}
3113 
3114 		if (params_to_set & SA_PARAM_COMPRESSION)
3115 			bcopy(ccomp, cpage, sizeof (sa_comp_t));
3116 
3117 		/*
3118 		 * The retry count is the only CCB field that might have been
3119 		 * changed that we care about, so reset it back to 1.
3120 		 */
3121 		ccb->ccb_h.retry_count = 1;
3122 		cam_periph_runccb(ccb, saerror, 0, sense_flags,
3123 		    softc->device_stats);
3124 	}
3125 
3126 	xpt_release_ccb(ccb);
3127 
3128 	if (ccomp != NULL)
3129 		free(ccomp, M_SCSISA);
3130 
3131 	if (params_to_set & SA_PARAM_COMPRESSION) {
3132 		if (error) {
3133 			softc->flags &= ~SA_FLAG_COMP_ENABLED;
3134 			/*
3135 			 * Even if we get an error setting compression,
3136 			 * do not say that we don't support it. We could
3137 			 * have been wrong, or it may be media specific.
3138 			 *	softc->flags &= ~SA_FLAG_COMP_SUPP;
3139 			 */
3140 			softc->saved_comp_algorithm = softc->comp_algorithm;
3141 			softc->comp_algorithm = 0;
3142 		} else {
3143 			softc->flags |= SA_FLAG_COMP_ENABLED;
3144 			softc->comp_algorithm = calg;
3145 		}
3146 	}
3147 
3148 	free(mode_buffer, M_SCSISA);
3149 	return (error);
3150 }
3151 
3152 static void
3153 saprevent(struct cam_periph *periph, int action)
3154 {
3155 	struct	sa_softc *softc;
3156 	union	ccb *ccb;
3157 	int	error, sf;
3158 
3159 	softc = (struct sa_softc *)periph->softc;
3160 
3161 	if ((action == PR_ALLOW) && (softc->flags & SA_FLAG_TAPE_LOCKED) == 0)
3162 		return;
3163 	if ((action == PR_PREVENT) && (softc->flags & SA_FLAG_TAPE_LOCKED) != 0)
3164 		return;
3165 
3166 	/*
3167 	 * We can be quiet about illegal requests.
3168 	 */
3169 	if (CAM_DEBUGGED(periph->path, CAM_DEBUG_INFO)) {
3170 		sf = 0;
3171 	} else
3172 		sf = SF_QUIET_IR;
3173 
3174 	ccb = cam_periph_getccb(periph, 1);
3175 
3176 	/* It is safe to retry this operation */
3177 	scsi_prevent(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, action,
3178 	    SSD_FULL_SIZE, SCSIOP_TIMEOUT);
3179 
3180 	error = cam_periph_runccb(ccb, saerror, 0, sf, softc->device_stats);
3181 	if (error == 0) {
3182 		if (action == PR_ALLOW)
3183 			softc->flags &= ~SA_FLAG_TAPE_LOCKED;
3184 		else
3185 			softc->flags |= SA_FLAG_TAPE_LOCKED;
3186 	}
3187 
3188 	xpt_release_ccb(ccb);
3189 }
3190 
3191 static int
3192 sarewind(struct cam_periph *periph)
3193 {
3194 	union	ccb *ccb;
3195 	struct	sa_softc *softc;
3196 	int	error;
3197 
3198 	softc = (struct sa_softc *)periph->softc;
3199 
3200 	ccb = cam_periph_getccb(periph, 1);
3201 
3202 	/* It is safe to retry this operation */
3203 	scsi_rewind(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG, FALSE,
3204 	    SSD_FULL_SIZE, REWIND_TIMEOUT);
3205 
3206 	softc->dsreg = MTIO_DSREG_REW;
3207 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3208 	softc->dsreg = MTIO_DSREG_REST;
3209 
3210 	xpt_release_ccb(ccb);
3211 	if (error == 0)
3212 		softc->fileno = softc->blkno = (daddr_t) 0;
3213 	else
3214 		softc->fileno = softc->blkno = (daddr_t) -1;
3215 	return (error);
3216 }
3217 
3218 static int
3219 saspace(struct cam_periph *periph, int count, scsi_space_code code)
3220 {
3221 	union	ccb *ccb;
3222 	struct	sa_softc *softc;
3223 	int	error;
3224 
3225 	softc = (struct sa_softc *)periph->softc;
3226 
3227 	ccb = cam_periph_getccb(periph, 1);
3228 
3229 	/* This cannot be retried */
3230 
3231 	scsi_space(&ccb->csio, 0, sadone, MSG_SIMPLE_Q_TAG, code, count,
3232 	    SSD_FULL_SIZE, SPACE_TIMEOUT);
3233 
3234 	/*
3235 	 * Clear residual because we will be using it.
3236 	 */
3237 	softc->last_ctl_resid = 0;
3238 
3239 	softc->dsreg = (count < 0)? MTIO_DSREG_REV : MTIO_DSREG_FWD;
3240 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3241 	softc->dsreg = MTIO_DSREG_REST;
3242 
3243 	xpt_release_ccb(ccb);
3244 
3245 	/*
3246 	 * If a spacing operation has failed, we need to invalidate
3247 	 * this mount.
3248 	 *
3249 	 * If the spacing operation was setmarks or to end of recorded data,
3250 	 * we no longer know our relative position.
3251 	 *
3252 	 * If the spacing operations was spacing files in reverse, we
3253 	 * take account of the residual, but still check against less
3254 	 * than zero- if we've gone negative, we must have hit BOT.
3255 	 *
3256 	 * If the spacing operations was spacing records in reverse and
3257 	 * we have a residual, we've either hit BOT or hit a filemark.
3258 	 * In the former case, we know our new record number (0). In
3259 	 * the latter case, we have absolutely no idea what the real
3260 	 * record number is- we've stopped between the end of the last
3261 	 * record in the previous file and the filemark that stopped
3262 	 * our spacing backwards.
3263 	 */
3264 	if (error) {
3265 		softc->fileno = softc->blkno = (daddr_t) -1;
3266 	} else if (code == SS_SETMARKS || code == SS_EOD) {
3267 		softc->fileno = softc->blkno = (daddr_t) -1;
3268 	} else if (code == SS_FILEMARKS && softc->fileno != (daddr_t) -1) {
3269 		softc->fileno += (count - softc->last_ctl_resid);
3270 		if (softc->fileno < 0)	/* we must of hit BOT */
3271 			softc->fileno = 0;
3272 		softc->blkno = 0;
3273 	} else if (code == SS_BLOCKS && softc->blkno != (daddr_t) -1) {
3274 		softc->blkno += (count - softc->last_ctl_resid);
3275 		if (count < 0) {
3276 			if (softc->last_ctl_resid || softc->blkno < 0) {
3277 				if (softc->fileno == 0) {
3278 					softc->blkno = 0;
3279 				} else {
3280 					softc->blkno = (daddr_t) -1;
3281 				}
3282 			}
3283 		}
3284 	}
3285 	return (error);
3286 }
3287 
3288 static int
3289 sawritefilemarks(struct cam_periph *periph, int nmarks, int setmarks)
3290 {
3291 	union	ccb *ccb;
3292 	struct	sa_softc *softc;
3293 	int	error, nwm = 0;
3294 
3295 	softc = (struct sa_softc *)periph->softc;
3296 	if (softc->open_rdonly)
3297 		return (EBADF);
3298 
3299 	ccb = cam_periph_getccb(periph, 1);
3300 	/*
3301 	 * Clear residual because we will be using it.
3302 	 */
3303 	softc->last_ctl_resid = 0;
3304 
3305 	softc->dsreg = MTIO_DSREG_FMK;
3306 	/* this *must* not be retried */
3307 	scsi_write_filemarks(&ccb->csio, 0, sadone, MSG_SIMPLE_Q_TAG,
3308 	    FALSE, setmarks, nmarks, SSD_FULL_SIZE, IO_TIMEOUT);
3309 	softc->dsreg = MTIO_DSREG_REST;
3310 
3311 
3312 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3313 
3314 	if (error == 0 && nmarks) {
3315 		struct sa_softc *softc = (struct sa_softc *)periph->softc;
3316 		nwm = nmarks - softc->last_ctl_resid;
3317 		softc->filemarks += nwm;
3318 	}
3319 
3320 	xpt_release_ccb(ccb);
3321 
3322 	/*
3323 	 * Update relative positions (if we're doing that).
3324 	 */
3325 	if (error) {
3326 		softc->fileno = softc->blkno = (daddr_t) -1;
3327 	} else if (softc->fileno != (daddr_t) -1) {
3328 		softc->fileno += nwm;
3329 		softc->blkno = 0;
3330 	}
3331 	return (error);
3332 }
3333 
3334 static int
3335 sardpos(struct cam_periph *periph, int hard, u_int32_t *blkptr)
3336 {
3337 	struct scsi_tape_position_data loc;
3338 	union ccb *ccb;
3339 	struct sa_softc *softc = (struct sa_softc *)periph->softc;
3340 	int error;
3341 
3342 	/*
3343 	 * We try and flush any buffered writes here if we were writing
3344 	 * and we're trying to get hardware block position. It eats
3345 	 * up performance substantially, but I'm wary of drive firmware.
3346 	 *
3347 	 * I think that *logical* block position is probably okay-
3348 	 * but hardware block position might have to wait for data
3349 	 * to hit media to be valid. Caveat Emptor.
3350 	 */
3351 
3352 	if (hard && (softc->flags & SA_FLAG_TAPE_WRITTEN)) {
3353 		error = sawritefilemarks(periph, 0, 0);
3354 		if (error && error != EACCES)
3355 			return (error);
3356 	}
3357 
3358 	ccb = cam_periph_getccb(periph, 1);
3359 	scsi_read_position(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
3360 	    hard, &loc, SSD_FULL_SIZE, SCSIOP_TIMEOUT);
3361 	softc->dsreg = MTIO_DSREG_RBSY;
3362 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3363 	softc->dsreg = MTIO_DSREG_REST;
3364 
3365 	if (error == 0) {
3366 		if (loc.flags & SA_RPOS_UNCERTAIN) {
3367 			error = EINVAL;		/* nothing is certain */
3368 		} else {
3369 			*blkptr = scsi_4btoul(loc.firstblk);
3370 		}
3371 	}
3372 
3373 	xpt_release_ccb(ccb);
3374 	return (error);
3375 }
3376 
3377 static int
3378 sasetpos(struct cam_periph *periph, int hard, u_int32_t *blkptr)
3379 {
3380 	union ccb *ccb;
3381 	struct sa_softc *softc;
3382 	int error;
3383 
3384 	/*
3385 	 * We used to try and flush any buffered writes here.
3386 	 * Now we push this onto user applications to either
3387 	 * flush the pending writes themselves (via a zero count
3388 	 * WRITE FILEMARKS command) or they can trust their tape
3389 	 * drive to do this correctly for them.
3390  	 */
3391 
3392 	softc = (struct sa_softc *)periph->softc;
3393 	ccb = cam_periph_getccb(periph, 1);
3394 
3395 
3396 	scsi_set_position(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
3397 	    hard, *blkptr, SSD_FULL_SIZE, SPACE_TIMEOUT);
3398 
3399 
3400 	softc->dsreg = MTIO_DSREG_POS;
3401 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3402 	softc->dsreg = MTIO_DSREG_REST;
3403 	xpt_release_ccb(ccb);
3404 	/*
3405 	 * Note relative file && block number position as now unknown.
3406 	 */
3407 	softc->fileno = softc->blkno = (daddr_t) -1;
3408 	return (error);
3409 }
3410 
3411 static int
3412 saretension(struct cam_periph *periph)
3413 {
3414 	union ccb *ccb;
3415 	struct sa_softc *softc;
3416 	int error;
3417 
3418 	softc = (struct sa_softc *)periph->softc;
3419 
3420 	ccb = cam_periph_getccb(periph, 1);
3421 
3422 	/* It is safe to retry this operation */
3423 	scsi_load_unload(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
3424 	    FALSE, TRUE,  TRUE, SSD_FULL_SIZE, ERASE_TIMEOUT);
3425 
3426 	softc->dsreg = MTIO_DSREG_TEN;
3427 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3428 	softc->dsreg = MTIO_DSREG_REST;
3429 
3430 	xpt_release_ccb(ccb);
3431 	if (error == 0)
3432 		softc->fileno = softc->blkno = (daddr_t) 0;
3433 	else
3434 		softc->fileno = softc->blkno = (daddr_t) -1;
3435 	return (error);
3436 }
3437 
3438 static int
3439 sareservereleaseunit(struct cam_periph *periph, int reserve)
3440 {
3441 	union ccb *ccb;
3442 	struct sa_softc *softc;
3443 	int error;
3444 
3445 	softc = (struct sa_softc *)periph->softc;
3446 	ccb = cam_periph_getccb(periph,  1);
3447 
3448 	/* It is safe to retry this operation */
3449 	scsi_reserve_release_unit(&ccb->csio, 2, sadone, MSG_SIMPLE_Q_TAG,
3450 	    FALSE,  0, SSD_FULL_SIZE,  SCSIOP_TIMEOUT, reserve);
3451 	softc->dsreg = MTIO_DSREG_RBSY;
3452 	error = cam_periph_runccb(ccb, saerror, 0,
3453 	    SF_RETRY_UA | SF_NO_PRINT, softc->device_stats);
3454 	softc->dsreg = MTIO_DSREG_REST;
3455 	xpt_release_ccb(ccb);
3456 
3457 	/*
3458 	 * If the error was Illegal Request, then the device doesn't support
3459 	 * RESERVE/RELEASE. This is not an error.
3460 	 */
3461 	if (error == EINVAL) {
3462 		error = 0;
3463 	}
3464 
3465 	return (error);
3466 }
3467 
3468 static int
3469 saloadunload(struct cam_periph *periph, int load)
3470 {
3471 	union	ccb *ccb;
3472 	struct	sa_softc *softc;
3473 	int	error;
3474 
3475 	softc = (struct sa_softc *)periph->softc;
3476 
3477 	ccb = cam_periph_getccb(periph, 1);
3478 
3479 	/* It is safe to retry this operation */
3480 	scsi_load_unload(&ccb->csio, 5, sadone, MSG_SIMPLE_Q_TAG, FALSE,
3481 	    FALSE, FALSE, load, SSD_FULL_SIZE, REWIND_TIMEOUT);
3482 
3483 	softc->dsreg = (load)? MTIO_DSREG_LD : MTIO_DSREG_UNL;
3484 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3485 	softc->dsreg = MTIO_DSREG_REST;
3486 	xpt_release_ccb(ccb);
3487 
3488 	if (error || load == 0)
3489 		softc->fileno = softc->blkno = (daddr_t) -1;
3490 	else if (error == 0)
3491 		softc->fileno = softc->blkno = (daddr_t) 0;
3492 	return (error);
3493 }
3494 
3495 static int
3496 saerase(struct cam_periph *periph, int longerase)
3497 {
3498 
3499 	union	ccb *ccb;
3500 	struct	sa_softc *softc;
3501 	int error;
3502 
3503 	softc = (struct sa_softc *)periph->softc;
3504 	if (softc->open_rdonly)
3505 		return (EBADF);
3506 
3507 	ccb = cam_periph_getccb(periph, 1);
3508 
3509 	scsi_erase(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG, FALSE, longerase,
3510 	    SSD_FULL_SIZE, ERASE_TIMEOUT);
3511 
3512 	softc->dsreg = MTIO_DSREG_ZER;
3513 	error = cam_periph_runccb(ccb, saerror, 0, 0, softc->device_stats);
3514 	softc->dsreg = MTIO_DSREG_REST;
3515 
3516 	xpt_release_ccb(ccb);
3517 	return (error);
3518 }
3519 
3520 #endif /* _KERNEL */
3521 
3522 /*
3523  * Read tape block limits command.
3524  */
3525 void
3526 scsi_read_block_limits(struct ccb_scsiio *csio, u_int32_t retries,
3527 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3528 		   u_int8_t tag_action,
3529 		   struct scsi_read_block_limits_data *rlimit_buf,
3530 		   u_int8_t sense_len, u_int32_t timeout)
3531 {
3532 	struct scsi_read_block_limits *scsi_cmd;
3533 
3534 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_IN, tag_action,
3535 	     (u_int8_t *)rlimit_buf, sizeof(*rlimit_buf), sense_len,
3536 	     sizeof(*scsi_cmd), timeout);
3537 
3538 	scsi_cmd = (struct scsi_read_block_limits *)&csio->cdb_io.cdb_bytes;
3539 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3540 	scsi_cmd->opcode = READ_BLOCK_LIMITS;
3541 }
3542 
3543 void
3544 scsi_sa_read_write(struct ccb_scsiio *csio, u_int32_t retries,
3545 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3546 		   u_int8_t tag_action, int readop, int sli,
3547 		   int fixed, u_int32_t length, u_int8_t *data_ptr,
3548 		   u_int32_t dxfer_len, u_int8_t sense_len, u_int32_t timeout)
3549 {
3550 	struct scsi_sa_rw *scsi_cmd;
3551 	int read;
3552 
3553 	read = (readop & SCSI_RW_DIRMASK) == SCSI_RW_READ;
3554 
3555 	scsi_cmd = (struct scsi_sa_rw *)&csio->cdb_io.cdb_bytes;
3556 	scsi_cmd->opcode = read ? SA_READ : SA_WRITE;
3557 	scsi_cmd->sli_fixed = 0;
3558 	if (sli && read)
3559 		scsi_cmd->sli_fixed |= SAR_SLI;
3560 	if (fixed)
3561 		scsi_cmd->sli_fixed |= SARW_FIXED;
3562 	scsi_ulto3b(length, scsi_cmd->length);
3563 	scsi_cmd->control = 0;
3564 
3565 	cam_fill_csio(csio, retries, cbfcnp, (read ? CAM_DIR_IN : CAM_DIR_OUT) |
3566 	    ((readop & SCSI_RW_BIO) != 0 ? CAM_DATA_BIO : 0),
3567 	    tag_action, data_ptr, dxfer_len, sense_len,
3568 	    sizeof(*scsi_cmd), timeout);
3569 }
3570 
3571 void
3572 scsi_load_unload(struct ccb_scsiio *csio, u_int32_t retries,
3573 		 void (*cbfcnp)(struct cam_periph *, union ccb *),
3574 		 u_int8_t tag_action, int immediate, int eot,
3575 		 int reten, int load, u_int8_t sense_len,
3576 		 u_int32_t timeout)
3577 {
3578 	struct scsi_load_unload *scsi_cmd;
3579 
3580 	scsi_cmd = (struct scsi_load_unload *)&csio->cdb_io.cdb_bytes;
3581 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3582 	scsi_cmd->opcode = LOAD_UNLOAD;
3583 	if (immediate)
3584 		scsi_cmd->immediate = SLU_IMMED;
3585 	if (eot)
3586 		scsi_cmd->eot_reten_load |= SLU_EOT;
3587 	if (reten)
3588 		scsi_cmd->eot_reten_load |= SLU_RETEN;
3589 	if (load)
3590 		scsi_cmd->eot_reten_load |= SLU_LOAD;
3591 
3592 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action,
3593 	    NULL, 0, sense_len, sizeof(*scsi_cmd), timeout);
3594 }
3595 
3596 void
3597 scsi_rewind(struct ccb_scsiio *csio, u_int32_t retries,
3598 	    void (*cbfcnp)(struct cam_periph *, union ccb *),
3599 	    u_int8_t tag_action, int immediate, u_int8_t sense_len,
3600 	    u_int32_t timeout)
3601 {
3602 	struct scsi_rewind *scsi_cmd;
3603 
3604 	scsi_cmd = (struct scsi_rewind *)&csio->cdb_io.cdb_bytes;
3605 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3606 	scsi_cmd->opcode = REWIND;
3607 	if (immediate)
3608 		scsi_cmd->immediate = SREW_IMMED;
3609 
3610 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3611 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3612 }
3613 
3614 void
3615 scsi_space(struct ccb_scsiio *csio, u_int32_t retries,
3616 	   void (*cbfcnp)(struct cam_periph *, union ccb *),
3617 	   u_int8_t tag_action, scsi_space_code code,
3618 	   u_int32_t count, u_int8_t sense_len, u_int32_t timeout)
3619 {
3620 	struct scsi_space *scsi_cmd;
3621 
3622 	scsi_cmd = (struct scsi_space *)&csio->cdb_io.cdb_bytes;
3623 	scsi_cmd->opcode = SPACE;
3624 	scsi_cmd->code = code;
3625 	scsi_ulto3b(count, scsi_cmd->count);
3626 	scsi_cmd->control = 0;
3627 
3628 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3629 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3630 }
3631 
3632 void
3633 scsi_write_filemarks(struct ccb_scsiio *csio, u_int32_t retries,
3634 		     void (*cbfcnp)(struct cam_periph *, union ccb *),
3635 		     u_int8_t tag_action, int immediate, int setmark,
3636 		     u_int32_t num_marks, u_int8_t sense_len,
3637 		     u_int32_t timeout)
3638 {
3639 	struct scsi_write_filemarks *scsi_cmd;
3640 
3641 	scsi_cmd = (struct scsi_write_filemarks *)&csio->cdb_io.cdb_bytes;
3642 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3643 	scsi_cmd->opcode = WRITE_FILEMARKS;
3644 	if (immediate)
3645 		scsi_cmd->byte2 |= SWFMRK_IMMED;
3646 	if (setmark)
3647 		scsi_cmd->byte2 |= SWFMRK_WSMK;
3648 
3649 	scsi_ulto3b(num_marks, scsi_cmd->num_marks);
3650 
3651 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3652 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3653 }
3654 
3655 /*
3656  * The reserve and release unit commands differ only by their opcodes.
3657  */
3658 void
3659 scsi_reserve_release_unit(struct ccb_scsiio *csio, u_int32_t retries,
3660 			  void (*cbfcnp)(struct cam_periph *, union ccb *),
3661 			  u_int8_t tag_action, int third_party,
3662 			  int third_party_id, u_int8_t sense_len,
3663 			  u_int32_t timeout, int reserve)
3664 {
3665 	struct scsi_reserve_release_unit *scsi_cmd;
3666 
3667 	scsi_cmd = (struct scsi_reserve_release_unit *)&csio->cdb_io.cdb_bytes;
3668 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3669 
3670 	if (reserve)
3671 		scsi_cmd->opcode = RESERVE_UNIT;
3672 	else
3673 		scsi_cmd->opcode = RELEASE_UNIT;
3674 
3675 	if (third_party) {
3676 		scsi_cmd->lun_thirdparty |= SRRU_3RD_PARTY;
3677 		scsi_cmd->lun_thirdparty |=
3678 			((third_party_id << SRRU_3RD_SHAMT) & SRRU_3RD_MASK);
3679 	}
3680 
3681 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3682 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3683 }
3684 
3685 void
3686 scsi_erase(struct ccb_scsiio *csio, u_int32_t retries,
3687 	   void (*cbfcnp)(struct cam_periph *, union ccb *),
3688 	   u_int8_t tag_action, int immediate, int long_erase,
3689 	   u_int8_t sense_len, u_int32_t timeout)
3690 {
3691 	struct scsi_erase *scsi_cmd;
3692 
3693 	scsi_cmd = (struct scsi_erase *)&csio->cdb_io.cdb_bytes;
3694 	bzero(scsi_cmd, sizeof(*scsi_cmd));
3695 
3696 	scsi_cmd->opcode = ERASE;
3697 
3698 	if (immediate)
3699 		scsi_cmd->lun_imm_long |= SE_IMMED;
3700 
3701 	if (long_erase)
3702 		scsi_cmd->lun_imm_long |= SE_LONG;
3703 
3704 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action, NULL,
3705 	    0, sense_len, sizeof(*scsi_cmd), timeout);
3706 }
3707 
3708 /*
3709  * Read Tape Position command.
3710  */
3711 void
3712 scsi_read_position(struct ccb_scsiio *csio, u_int32_t retries,
3713 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3714 		   u_int8_t tag_action, int hardsoft,
3715 		   struct scsi_tape_position_data *sbp,
3716 		   u_int8_t sense_len, u_int32_t timeout)
3717 {
3718 	struct scsi_tape_read_position *scmd;
3719 
3720 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_IN, tag_action,
3721 	    (u_int8_t *)sbp, sizeof (*sbp), sense_len, sizeof(*scmd), timeout);
3722 	scmd = (struct scsi_tape_read_position *)&csio->cdb_io.cdb_bytes;
3723 	bzero(scmd, sizeof(*scmd));
3724 	scmd->opcode = READ_POSITION;
3725 	scmd->byte1 = hardsoft;
3726 }
3727 
3728 /*
3729  * Set Tape Position command.
3730  */
3731 void
3732 scsi_set_position(struct ccb_scsiio *csio, u_int32_t retries,
3733 		   void (*cbfcnp)(struct cam_periph *, union ccb *),
3734 		   u_int8_t tag_action, int hardsoft, u_int32_t blkno,
3735 		   u_int8_t sense_len, u_int32_t timeout)
3736 {
3737 	struct scsi_tape_locate *scmd;
3738 
3739 	cam_fill_csio(csio, retries, cbfcnp, CAM_DIR_NONE, tag_action,
3740 	    (u_int8_t *)NULL, 0, sense_len, sizeof(*scmd), timeout);
3741 	scmd = (struct scsi_tape_locate *)&csio->cdb_io.cdb_bytes;
3742 	bzero(scmd, sizeof(*scmd));
3743 	scmd->opcode = LOCATE;
3744 	if (hardsoft)
3745 		scmd->byte1 |= SA_SPOS_BT;
3746 	scsi_ulto4b(blkno, scmd->blkaddr);
3747 }
3748