xref: /netbsd-src/sys/dev/scsipi/st.c (revision ae1bfcddc410612bc8c58b807e1830becb69a24c)
1 /*
2  * Copyright (c) 1994 Charles Hannum.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. All advertising materials mentioning features or use of this software
13  *    must display the following acknowledgement:
14  *	This product includes software developed by Charles Hannum.
15  * 4. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  *	$Id: st.c,v 1.31 1994/05/11 09:53:45 mycroft Exp $
30  */
31 
32 /*
33  * Originally written by Julian Elischer (julian@tfs.com)
34  * for TRW Financial Systems for use under the MACH(2.5) operating system.
35  *
36  * TRW Financial Systems, in accordance with their agreement with Carnegie
37  * Mellon University, makes this software available to CMU to distribute
38  * or use in any manner that they see fit as long as this message is kept with
39  * the software. For this reason TFS also grants any other persons or
40  * organisations permission to use or modify this software.
41  *
42  * TFS supplies this software to be publicly redistributed
43  * on the understanding that TFS is not responsible for the correct
44  * functioning of this software in any circumstances.
45  *
46  * Ported to run under 386BSD by Julian Elischer (julian@tfs.com) Sept 1992
47  * major changes by Julian Elischer (julian@jules.dialix.oz.au) May 1993
48  */
49 
50 /*
51  * To do:
52  * work out some better way of guessing what a good timeout is going
53  * to be depending on whether we expect to retension or not.
54  */
55 
56 #include <sys/types.h>
57 #include <sys/param.h>
58 #include <sys/systm.h>
59 #include <sys/fcntl.h>
60 #include <sys/errno.h>
61 #include <sys/ioctl.h>
62 #include <sys/malloc.h>
63 #include <sys/buf.h>
64 #include <sys/proc.h>
65 #include <sys/user.h>
66 #include <sys/mtio.h>
67 #include <sys/device.h>
68 
69 #include <scsi/scsi_all.h>
70 #include <scsi/scsi_tape.h>
71 #include <scsi/scsiconf.h>
72 
73 /* Defines for device specific stuff */
74 #define	PAGE_0_SENSE_DATA_SIZE	12
75 #define DEF_FIXED_BSIZE  512
76 #define	ST_RETRIES	4	/* only on non IO commands */
77 
78 #define STMODE(z)	( minor(z)       & 0x03)
79 #define STDSTY(z)	((minor(z) >> 2) & 0x03)
80 #define STUNIT(z)	((minor(z) >> 4)       )
81 #define CTLMODE	3
82 
83 #define SCSI_2_MAX_DENSITY_CODE	0x17	/* maximum density code specified
84 					 * in SCSI II spec. */
85 /*
86  * Define various devices that we know mis-behave in some way,
87  * and note how they are bad, so we can correct for them
88  */
89 struct modes {
90 	u_int blksiz;
91 	u_int quirks;		/* same definitions as in rogues */
92 	char density;
93 	char spare[3];
94 };
95 
96 struct rogues {
97 	char *manu;
98 	char *model;
99 	char *version;
100 	u_int quirks;		/* valid for all modes */
101 	struct modes modes[4];
102 };
103 
104 /* define behaviour codes (quirks) */
105 #define	ST_Q_NEEDS_PAGE_0	0x00001
106 #define	ST_Q_FORCE_FIXED_MODE	0x00002
107 #define	ST_Q_FORCE_VAR_MODE	0x00004
108 #define	ST_Q_SENSE_HELP		0x00008	/* must do READ for good MODE SENSE */
109 #define	ST_Q_IGNORE_LOADS	0x00010
110 #define	ST_Q_BLKSIZ		0x00020	/* variable-block media_blksiz > 0 */
111 
112 static struct rogues gallery[] =	/* ends with an all-null entry */
113 {
114     {"pre-scsi", " unknown model  ", "????",
115 	0,
116 	{
117 	    {512, ST_Q_FORCE_FIXED_MODE, 0},		/* minor 0-3 */
118 	    {512, ST_Q_FORCE_FIXED_MODE, QIC_24},	/* minor 4-7 */
119 	    {0, ST_Q_FORCE_VAR_MODE, HALFINCH_1600},	/* minor 8-11 */
120 	    {0, ST_Q_FORCE_VAR_MODE, HALFINCH_6250}	/* minor 12-15 */
121 	}
122     },
123     {"TANDBERG", " TDC 3600", "????",
124 	ST_Q_NEEDS_PAGE_0,
125 	{
126 	    {0, 0, 0},					/* minor 0-3 */
127 	    {0, ST_Q_FORCE_VAR_MODE, QIC_525},		/* minor 4-7 */
128 	    {0, 0, QIC_150},				/* minor 8-11 */
129 	    {0, 0, QIC_120}				/* minor 12-15 */
130 	}
131     },
132     /*
133      * At least -005 and -007 need this.  I'll assume they all do unless I
134      * hear otherwise.  - mycroft, 31MAR1994
135      */
136     {"ARCHIVE ", "VIPER 2525 25462", "????",
137 	0,
138 	{
139 	    {0, ST_Q_SENSE_HELP, 0},			/* minor 0-3 */
140 	    {0, ST_Q_SENSE_HELP, QIC_525},		/* minor 4-7 */
141 	    {0, 0, QIC_150},				/* minor 8-11 */
142 	    {0, 0, QIC_120}				/* minor 12-15 */
143 	}
144     },
145     /*
146      * One user reports that this works for her tape drive.  It probably
147      * needs more work.  - mycroft, 09APR1994
148      */
149     {"SANKYO  ", "CP525", "????",
150 	0,
151 	{
152 	    {512, ST_Q_FORCE_FIXED_MODE, 0},		/* minor 0-3 */
153 	    {512, ST_Q_FORCE_FIXED_MODE, QIC_525},	/* minor 4-7 */
154 	    {0, 0, QIC_150},				/* minor 8-11 */
155 	    {0, 0, QIC_120}				/* minor 12-15 */
156 	}
157     },
158     {"ARCHIVE ", "VIPER 150", "????",
159 	ST_Q_NEEDS_PAGE_0,
160 	{
161 	    {0, 0, 0},					/* minor 0-3 */
162 	    {0, 0, QIC_150},				/* minor 4-7 */
163 	    {0, 0, QIC_120},				/* minor 8-11 */
164 	    {0, 0, QIC_24}				/* minor 12-15 */
165 	}
166     },
167     {"WANGTEK ", "5525ES SCSI REV7", "????",
168 	0,
169 	{
170 	    {0, 0, 0},					/* minor 0-3 */
171 	    {0, ST_Q_BLKSIZ, QIC_525},			/* minor 4-7 */
172 	    {0, 0, QIC_150},				/* minor 8-11 */
173 	    {0, 0, QIC_120}				/* minor 12-15 */
174 	}
175     },
176     {"WangDAT ", "Model 1300", "????",
177 	0,
178 	{
179 	    {0, 0, 0},					/* minor 0-3 */
180 	    {512, ST_Q_FORCE_FIXED_MODE, DDS},		/* minor 4-7 */
181 	    {1024, ST_Q_FORCE_FIXED_MODE, DDS},		/* minor 8-11 */
182 	    {0, ST_Q_FORCE_VAR_MODE, DDS}		/* minor 12-15 */
183 	}
184     },
185     {0}
186 };
187 
188 #define NOEJECT 0
189 #define EJECT 1
190 
191 struct st_data {
192 	struct device sc_dev;
193 /*--------------------present operating parameters, flags etc.----------------*/
194 	int flags;		/* see below                          */
195 	u_int blksiz;		/* blksiz we are using                */
196 	u_int density;		/* present density                    */
197 	u_int quirks;		/* quirks for the open mode           */
198 	u_int last_dsty;	/* last density openned               */
199 /*--------------------device/scsi parameters----------------------------------*/
200 	struct scsi_link *sc_link;	/* our link to the adpter etc.        */
201 /*--------------------parameters reported by the device ----------------------*/
202 	u_int blkmin;		/* min blk size                       */
203 	u_int blkmax;		/* max blk size                       */
204 	struct rogues *rogues;	/* if we have a rogue entry           */
205 /*--------------------parameters reported by the device for this media--------*/
206 	u_int numblks;		/* nominal blocks capacity            */
207 	u_int media_blksiz;	/* 0 if not ST_FIXEDBLOCKS            */
208 	u_int media_density;	/* this is what it said when asked    */
209 /*--------------------quirks for the whole drive------------------------------*/
210 	u_int drive_quirks;	/* quirks of this drive               */
211 /*--------------------How we should set up when openning each minor device----*/
212 	struct modes modes[4];	/* plus more for each mode            */
213 	u_int8  modeflags[4];	/* flags for the modes                */
214 #define DENSITY_SET_BY_USER	0x01
215 #define DENSITY_SET_BY_QUIRK	0x02
216 #define BLKSIZE_SET_BY_USER	0x04
217 #define BLKSIZE_SET_BY_QUIRK	0x08
218 /*--------------------storage for sense data returned by the drive------------*/
219 	u_char sense_data[12];		/*
220 					 * additional sense data needed
221 					 * for mode sense/select.
222 					 */
223 	struct buf buf_queue;		/* the queue of pending IO operations */
224 	struct scsi_xfer scsi_xfer;	/* scsi xfer struct for this drive */
225 	u_int xfer_block_wait;		/* is a process waiting? */
226 };
227 
228 void stattach __P((struct device *, struct device *, void *));
229 
230 struct cfdriver stcd = {
231 	NULL, "st", scsi_targmatch, stattach, DV_TAPE, sizeof(struct st_data)
232 };
233 
234 int	st_space __P((struct st_data *, int number, u_int what, int flags));
235 int	st_rewind __P((struct st_data *, u_int immediate, int flags));
236 int	st_mode_sense __P((struct st_data *, int flags));
237 int	st_decide_mode __P((struct st_data *, boolean first_read));
238 int	st_read_block_limits __P((struct st_data *, int flags));
239 int	st_touch_tape __P((struct st_data *));
240 int	st_write_filemarks __P((struct st_data *, int number, int flags));
241 int	st_load __P((struct st_data *, u_int type, int flags));
242 int	st_mode_select __P((struct st_data *, int flags));
243 void    ststrategy();
244 void    stminphys();
245 int	st_check_eod();
246 void    ststart();
247 void	st_unmount();
248 int	st_mount_tape();
249 void	st_loadquirks();
250 void	st_identify_drive();
251 int	st_interpret_sense();
252 
253 struct scsi_device st_switch = {
254 	st_interpret_sense,
255 	ststart,
256 	NULL,
257 	NULL,
258 	"st",
259 	0
260 };
261 
262 #define	ST_INFO_VALID	0x02
263 #define ST_OPEN		0x04
264 #define	ST_BLOCK_SET	0x08	/* block size, mode set by ioctl      */
265 #define	ST_WRITTEN	0x10	/* data have been written, EOD needed */
266 #define	ST_FIXEDBLOCKS	0x20
267 #define	ST_AT_FILEMARK	0x40
268 #define	ST_EIO_PENDING	0x80	/* we couldn't report it then (had data) */
269 #define	ST_NEW_MOUNT	0x100	/* still need to decide mode              */
270 #define	ST_READONLY	0x200	/* st_mode_sense says write protected */
271 #define	ST_FM_WRITTEN	0x400	/*
272 				 * EOF file mark written  -- used with
273 				 * ~ST_WRITTEN to indicate that multiple file
274 				 * marks have been written
275 				 */
276 #define	ST_BLANK_READ	0x800	/* BLANK CHECK encountered already */
277 #define	ST_2FM_AT_EOD	0x1000	/* write 2 file marks at EOD */
278 #define	ST_MOUNTED	0x2000	/* Device is presently mounted */
279 
280 #define	ST_PER_ACTION	(ST_AT_FILEMARK | ST_EIO_PENDING | ST_BLANK_READ)
281 #define	ST_PER_MOUNT	(ST_INFO_VALID | ST_BLOCK_SET | ST_WRITTEN | \
282 			ST_FIXEDBLOCKS | ST_READONLY | \
283 			ST_FM_WRITTEN | ST_2FM_AT_EOD | ST_PER_ACTION)
284 
285 /*
286  * The routine called by the low level scsi routine when it discovers
287  * A device suitable for this driver
288  */
289 void
290 stattach(parent, self, aux)
291 	struct device *parent, *self;
292 	void *aux;
293 {
294 	struct st_data *st = (void *)self;
295 	struct scsi_link *sc_link = aux;
296 
297 	SC_DEBUG(sc_link, SDEV_DB2, ("stattach: "));
298 
299 	sc_link->device = &st_switch;
300 	sc_link->dev_unit = st->sc_dev.dv_unit;
301 
302 	/*
303 	 * Store information needed to contact our base driver
304 	 */
305 	st->sc_link = sc_link;
306 
307 	/*
308 	 * Check if the drive is a known criminal and take
309 	 * Any steps needed to bring it into line
310 	 */
311 	st_identify_drive(st);
312 
313 	/*
314 	 * Use the subdriver to request information regarding
315 	 * the drive. We cannot use interrupts yet, so the
316 	 * request must specify this.
317 	 */
318 	printf(": %s", st->rogues ? "rogue, " : "");
319 	if (st_mode_sense(st, SCSI_NOSLEEP | SCSI_NOMASK | SCSI_SILENT))
320 		printf("drive offline\n");
321 	else if (scsi_test_unit_ready(sc_link,
322 	    SCSI_NOSLEEP | SCSI_NOMASK | SCSI_SILENT))
323 		printf("drive empty\n");
324 	else {
325 		printf("density code 0x%x, ", st->media_density);
326 		if (st->media_blksiz)
327 			printf("%d-byte", st->media_blksiz);
328 		else
329 			printf("variable");
330 		printf(" blocks, write-%s\n",
331 		    (st->flags & ST_READONLY) ? "protected" : "enabled");
332 	}
333 
334 	/*
335 	 * Set up the buf queue for this device
336 	 */
337 	st->buf_queue.b_active = 0;
338 	st->buf_queue.b_actf = 0;
339 	st->buf_queue.b_actb = &st->buf_queue.b_actf;
340 }
341 
342 /*
343  * Use the inquiry routine in 'scsi_base' to get drive info so we can
344  * Further tailor our behaviour.
345  */
346 void
347 st_identify_drive(st)
348 	struct st_data *st;
349 {
350 	struct scsi_inquiry_data inqbuf;
351 	struct rogues *finger;
352 	char manu[32];
353 	char model[32];
354 	char model2[32];
355 	char version[32];
356 	u_int model_len;
357 
358 	/*
359 	 * Get the device type information
360 	 */
361 	if (scsi_inquire(st->sc_link, &inqbuf,
362 	    SCSI_NOSLEEP | SCSI_NOMASK | SCSI_SILENT) != 0) {
363 		printf("%s: couldn't get device type, using default\n",
364 		    st->sc_dev.dv_xname);
365 		return;
366 	}
367 	if ((inqbuf.version & SID_ANSII) == 0) {
368 		/*
369 		 * If not advanced enough, use default values
370 		 */
371 		strncpy(manu, "pre-scsi", 8);
372 		manu[8] = 0;
373 		strncpy(model, " unknown model  ", 16);
374 		model[16] = 0;
375 		strncpy(version, "????", 4);
376 		version[4] = 0;
377 	} else {
378 		strncpy(manu, inqbuf.vendor, 8);
379 		manu[8] = 0;
380 		strncpy(model, inqbuf.product, 16);
381 		model[16] = 0;
382 		strncpy(version, inqbuf.revision, 4);
383 		version[4] = 0;
384 	}
385 
386 	/*
387 	 * Load the parameters for this kind of device, so we
388 	 * treat it as appropriate for each operating mode.
389 	 * Only check the number of characters in the array's
390 	 * model entry, not the entire model string returned.
391 	 */
392 	finger = gallery;
393 	while (finger->manu) {
394 		model_len = 0;
395 		while (finger->model[model_len] && (model_len < 32)) {
396 			model2[model_len] = model[model_len];
397 			model_len++;
398 		}
399 		model2[model_len] = 0;
400 		if ((strcmp(manu, finger->manu) == 0) &&
401 		    (strcmp(model2, finger->model) == 0 ||
402 		    strcmp("????????????????", finger->model) == 0) &&
403 		    (strcmp(version, finger->version) == 0 ||
404 		    strcmp("????", finger->version) == 0)) {
405 			st->rogues = finger;
406 			st->drive_quirks = finger->quirks;
407 			st->quirks = finger->quirks;	/* start value */
408 			st_loadquirks(st);
409 			break;
410 		} else
411 			finger++;	/* go to next suspect */
412 	}
413 }
414 
415 /*
416  * initialise the subdevices to the default (QUIRK) state.
417  * this will remove any setting made by the system operator or previous
418  * operations.
419  */
420 void
421 st_loadquirks(st)
422 	struct st_data *st;
423 {
424 	int i;
425 	struct	modes *mode;
426 	struct	modes *mode2;
427 
428 	if (!st->rogues)
429 		return;
430 	mode = st->rogues->modes;
431 	mode2 = st->modes;
432 	for (i = 0; i < 4; i++) {
433 		bzero(mode2, sizeof(struct modes));
434 		st->modeflags[i] &= ~(BLKSIZE_SET_BY_QUIRK |
435 		    DENSITY_SET_BY_QUIRK | BLKSIZE_SET_BY_USER |
436 		    DENSITY_SET_BY_USER);
437 		if (mode->blksiz && ((mode->quirks | st->drive_quirks) &
438 		    ST_Q_FORCE_FIXED_MODE)) {
439 			mode2->blksiz = mode->blksiz;
440 			st->modeflags[i] |= BLKSIZE_SET_BY_QUIRK;
441 		} else if ((mode->quirks | st->drive_quirks) &
442 		    ST_Q_FORCE_VAR_MODE) {
443 			mode2->blksiz = 0;
444 			st->modeflags[i] |= BLKSIZE_SET_BY_QUIRK;
445 		}
446 		if (mode->density) {
447 			mode2->density = mode->density;
448 			st->modeflags[i] |= DENSITY_SET_BY_QUIRK;
449 		}
450 		mode++;
451 		mode2++;
452 	}
453 }
454 
455 /*
456  * open the device.
457  */
458 int
459 stopen(dev, flags)
460 	dev_t dev;
461 	int flags;
462 {
463 	int unit;
464 	u_int mode, dsty;
465 	int error = 0;
466 	struct st_data *st;
467 	struct scsi_link *sc_link;
468 
469 	unit = STUNIT(dev);
470 	mode = STMODE(dev);
471 	dsty = STDSTY(dev);
472 
473 	if (unit >= stcd.cd_ndevs)
474 		return ENXIO;
475 	st = stcd.cd_devs[unit];
476 	if (!st)
477 		return ENXIO;
478 
479 	sc_link = st->sc_link;
480 	SC_DEBUG(sc_link, SDEV_DB1, ("open: dev=0x%x (unit %d (of %d))\n", dev,
481 	    unit, stcd.cd_ndevs));
482 
483 	if (st->flags & ST_OPEN)
484 		return EBUSY;
485 
486 	/*
487 	 * Throw out a dummy instruction to catch 'Unit attention
488 	 * errors (the error handling will invalidate all our
489 	 * device info if we get one, but otherwise, ignore it)
490 	 */
491 	scsi_test_unit_ready(sc_link, SCSI_SILENT);
492 
493 	sc_link->flags |= SDEV_OPEN;	/* unit attn are now errors */
494 	/*
495 	 * If the mode is 3 (e.g. minor = 3,7,11,15)
496 	 * then the device has been openned to set defaults
497 	 * This mode does NOT ALLOW I/O, only ioctls
498 	 */
499 	if (mode == CTLMODE)
500 		return 0;
501 
502 	/*
503 	 * Check that the device is ready to use (media loaded?)
504 	 * This time take notice of the return result
505 	 */
506 	if (error = (scsi_test_unit_ready(sc_link, 0))) {
507 		printf("%s: not ready\n", st->sc_dev.dv_xname);
508 		st_unmount(st, NOEJECT);
509 		return error;
510 	}
511 
512 	/*
513 	 * if it's a different mode, or if the media has been
514 	 * invalidated, unmount the tape from the previous
515 	 * session but continue with open processing
516 	 */
517 	if (st->last_dsty != dsty || !(sc_link->flags & SDEV_MEDIA_LOADED))
518 		st_unmount(st, NOEJECT);
519 
520 	/*
521 	 * If we are not mounted, then we should start a new
522 	 * mount session.
523 	 */
524 	if (!(st->flags & ST_MOUNTED)) {
525 		st_mount_tape(dev, flags);
526 		st->last_dsty = dsty;
527 	}
528 
529 	/*
530 	 * Make sure that a tape opened in write-only mode will have
531 	 * file marks written on it when closed, even if not written to.
532 	 * This is for SUN compatibility
533 	 */
534 	if ((flags & O_ACCMODE) == FWRITE)
535 		st->flags |= ST_WRITTEN;
536 
537 	SC_DEBUG(sc_link, SDEV_DB2, ("Open complete\n"));
538 
539 	st->flags |= ST_OPEN;
540 	return 0;
541 }
542 
543 /*
544  * close the device.. only called if we are the LAST
545  * occurence of an open device
546  */
547 int
548 stclose(dev)
549 	dev_t dev;
550 {
551 	int unit, mode;
552 	struct st_data *st;
553 	struct scsi_link *sc_link;
554 
555 	unit = STUNIT(dev);
556 	mode = STMODE(dev);
557 	st = stcd.cd_devs[unit];
558 	sc_link = st->sc_link;
559 
560 	SC_DEBUG(sc_link, SDEV_DB1, ("closing\n"));
561 	if ((st->flags & (ST_WRITTEN | ST_FM_WRITTEN)) == ST_WRITTEN)
562 		st_write_filemarks(st, 1, 0);
563 	switch (mode & 0x3) {
564 	case 0:
565 	case 3:		/* for now */
566 		st_unmount(st, NOEJECT);
567 		break;
568 	case 1:
569 		/* leave mounted unless media seems to have been removed */
570 		if (!(sc_link->flags & SDEV_MEDIA_LOADED))
571 			st_unmount(st, NOEJECT);
572 		break;
573 	case 2:
574 		st_unmount(st, EJECT);
575 		break;
576 	}
577 	sc_link->flags &= ~SDEV_OPEN;
578 	st->flags &= ~ST_OPEN;
579 	return 0;
580 }
581 
582 /*
583  * Start a new mount session.
584  * Copy in all the default parameters from the selected device mode.
585  * and try guess any that seem to be defaulted.
586  */
587 int
588 st_mount_tape(dev, flags)
589 	dev_t dev;
590 	int flags;
591 {
592 	int unit;
593 	u_int mode, dsty;
594 	struct st_data *st;
595 	struct scsi_link *sc_link;
596 	int error = 0;
597 
598 	unit = STUNIT(dev);
599 	mode = STMODE(dev);
600 	dsty = STDSTY(dev);
601 	st = stcd.cd_devs[unit];
602 	sc_link = st->sc_link;
603 
604 	if (st->flags & ST_MOUNTED)
605 		return 0;
606 
607 	SC_DEBUG(sc_link, SDEV_DB1, ("mounting\n "));
608 	st->flags |= ST_NEW_MOUNT;
609 	st->quirks = st->drive_quirks | st->modes[dsty].quirks;
610 	/*
611 	 * If the media is new, then make sure we give it a chance to
612 	 * to do a 'load' instruction.  (We assume it is new.)
613 	 */
614 	if (error = st_load(st, LD_LOAD, 0))
615 		return error;
616 	/*
617 	 * Throw another dummy instruction to catch
618 	 * 'Unit attention' errors. Some drives appear to give
619 	 * these after doing a Load instruction.
620 	 * (noteably some DAT drives)
621 	 */
622 	scsi_test_unit_ready(sc_link, SCSI_SILENT);
623 
624 	/*
625 	 * Some devices can't tell you much until they have been
626 	 * asked to look at the media. This quirk does this.
627 	 */
628 	if (st->quirks & ST_Q_SENSE_HELP)
629 		if (error = st_touch_tape(st))
630 			return error;
631 	/*
632 	 * Load the physical device parameters
633 	 * loads: blkmin, blkmax
634 	 */
635 	if (error = st_read_block_limits(st, 0))
636 		return error;
637 	/*
638 	 * Load the media dependent parameters
639 	 * includes: media_blksiz,media_density,numblks
640 	 * As we have a tape in, it should be reflected here.
641 	 * If not you may need the "quirk" above.
642 	 */
643 	if (error = st_mode_sense(st, 0))
644 		return error;
645 	/*
646 	 * If we have gained a permanent density from somewhere,
647 	 * then use it in preference to the one supplied by
648 	 * default by the driver.
649 	 */
650 	if (st->modeflags[dsty] & (DENSITY_SET_BY_QUIRK | DENSITY_SET_BY_USER))
651 		st->density = st->modes[dsty].density;
652 	else
653 		st->density = st->media_density;
654 	/*
655 	 * If we have gained a permanent blocksize
656 	 * then use it in preference to the one supplied by
657 	 * default by the driver.
658 	 */
659 	st->flags &= ~ST_FIXEDBLOCKS;
660 	if (st->modeflags[dsty] & (BLKSIZE_SET_BY_QUIRK | BLKSIZE_SET_BY_USER)) {
661 		st->blksiz = st->modes[dsty].blksiz;
662 		if (st->blksiz)
663 			st->flags |= ST_FIXEDBLOCKS;
664 	} else {
665 		if (error = st_decide_mode(st, FALSE))
666 			return error;
667 	}
668 	if (error = st_mode_select(st, 0)) {
669 		printf("%s: cannot set selected mode\n", st->sc_dev.dv_xname);
670 		return error;
671 	}
672 	scsi_prevent(sc_link, PR_PREVENT, 0);	/* who cares if it fails? */
673 	st->flags &= ~ST_NEW_MOUNT;
674 	st->flags |= ST_MOUNTED;
675 	sc_link->flags |= SDEV_MEDIA_LOADED;	/* move earlier? */
676 
677 	return 0;
678 }
679 
680 /*
681  * End the present mount session.
682  * Rewind, and optionally eject the tape.
683  * Reset various flags to indicate that all new
684  * operations require another mount operation
685  */
686 void
687 st_unmount(st, eject)
688 	struct st_data *st;
689 	boolean eject;
690 {
691 	struct scsi_link *sc_link = st->sc_link;
692 	int nmarks;
693 
694 	if (!(st->flags & ST_MOUNTED))
695 		return;
696 	SC_DEBUG(sc_link, SDEV_DB1, ("unmounting\n"));
697 	st_check_eod(st, FALSE, &nmarks, SCSI_SILENT);
698 	st_rewind(st, 0, SCSI_SILENT);
699 	scsi_prevent(sc_link, PR_ALLOW, SCSI_SILENT);
700 	if (eject)
701 		st_load(st, LD_UNLOAD, SCSI_SILENT);
702 	st->flags &= ~(ST_MOUNTED | ST_NEW_MOUNT);
703 	sc_link->flags &= ~SDEV_MEDIA_LOADED;
704 }
705 
706 /*
707  * Given all we know about the device, media, mode, 'quirks' and
708  * initial operation, make a decision as to how we should be set
709  * to run (regarding blocking and EOD marks)
710  */
711 int
712 st_decide_mode(st, first_read)
713 	struct st_data *st;
714 	boolean	first_read;
715 {
716 #ifdef SCSIDEBUG
717 	struct scsi_link *sc_link = st->sc_link;
718 #endif
719 
720 	SC_DEBUG(sc_link, SDEV_DB2, ("starting block mode decision\n"));
721 
722 	/*
723 	 * If the user hasn't already specified fixed or variable-length
724 	 * blocks and the block size (zero if variable-length), we'll
725 	 * have to try to figure them out ourselves.
726 	 *
727 	 * Our first shot at a method is, "The quirks made me do it!"
728 	 */
729 	switch (st->quirks & (ST_Q_FORCE_FIXED_MODE | ST_Q_FORCE_VAR_MODE)) {
730 	case (ST_Q_FORCE_FIXED_MODE | ST_Q_FORCE_VAR_MODE):
731 		printf("%s: bad quirks\n", st->sc_dev.dv_xname);
732 		return EINVAL;
733 	case ST_Q_FORCE_FIXED_MODE:	/*specified fixed, but not what size */
734 		st->flags |= ST_FIXEDBLOCKS;
735 		if (st->blkmin && (st->blkmin == st->blkmax))
736 			st->blksiz = st->blkmin;
737 		else if (st->media_blksiz > 0)
738 			st->blksiz = st->media_blksiz;
739 		else
740 			st->blksiz = DEF_FIXED_BSIZE;
741 		SC_DEBUG(sc_link, SDEV_DB3, ("Quirks force fixed mode(%d)\n",
742 			st->blksiz));
743 		goto done;
744 	case ST_Q_FORCE_VAR_MODE:
745 		st->flags &= ~ST_FIXEDBLOCKS;
746 		st->blksiz = 0;
747 		SC_DEBUG(sc_link, SDEV_DB3, ("Quirks force variable mode\n"));
748 		goto done;
749 	}
750 
751 	/*
752 	 * If the drive can only handle fixed-length blocks and only at
753 	 * one size, perhaps we should just do that.
754 	 */
755 	if (st->blkmin && (st->blkmin == st->blkmax)) {
756 		st->flags |= ST_FIXEDBLOCKS;
757 		st->blksiz = st->blkmin;
758 		SC_DEBUG(sc_link, SDEV_DB3,
759 		    ("blkmin == blkmax of %d\n", st->blkmin));
760 		goto done;
761 	}
762 	/*
763 	 * If the tape density mandates (or even suggests) use of fixed
764 	 * or variable-length blocks, comply.
765 	 */
766 	switch (st->density) {
767 	case HALFINCH_800:
768 	case HALFINCH_1600:
769 	case HALFINCH_6250:
770 	case DDS:
771 		st->flags &= ~ST_FIXEDBLOCKS;
772 		st->blksiz = 0;
773 		SC_DEBUG(sc_link, SDEV_DB3, ("density specified variable\n"));
774 		goto done;
775 	case QIC_11:
776 	case QIC_24:
777 	case QIC_120:
778 	case QIC_150:
779 	case QIC_525:
780 	case QIC_1320:
781 		st->flags |= ST_FIXEDBLOCKS;
782 		if (st->media_blksiz > 0)
783 			st->blksiz = st->media_blksiz;
784 		else
785 			st->blksiz = DEF_FIXED_BSIZE;
786 		SC_DEBUG(sc_link, SDEV_DB3, ("density specified fixed\n"));
787 		goto done;
788 	}
789 	/*
790 	 * If we're about to read the tape, perhaps we should choose
791 	 * fixed or variable-length blocks and block size according to
792 	 * what the drive found on the tape.
793 	 */
794 	if (first_read &&
795 	    (!(st->quirks & ST_Q_BLKSIZ) || (st->media_blksiz == 0) ||
796 	    (st->media_blksiz == DEF_FIXED_BSIZE) ||
797 	    (st->media_blksiz == 1024))) {
798 		if (st->media_blksiz == 0)
799 			st->flags &= ~ST_FIXEDBLOCKS;
800 		else
801 			st->flags |= ST_FIXEDBLOCKS;
802 		st->blksiz = st->media_blksiz;
803 		SC_DEBUG(sc_link, SDEV_DB3,
804 		    ("Used media_blksiz of %d\n", st->media_blksiz));
805 		goto done;
806 	}
807 	/*
808 	 * We're getting no hints from any direction.  Choose variable-
809 	 * length blocks arbitrarily.
810 	 */
811 	st->flags &= ~ST_FIXEDBLOCKS;
812 	st->blksiz = 0;
813 	SC_DEBUG(sc_link, SDEV_DB3,
814 	    ("Give up and default to variable mode\n"));
815 done:
816 
817 	/*
818 	 * Decide whether or not to write two file marks to signify end-
819 	 * of-data.  Make the decision as a function of density.  If
820 	 * the decision is not to use a second file mark, the SCSI BLANK
821 	 * CHECK condition code will be recognized as end-of-data when
822 	 * first read.
823 	 * (I think this should be a by-product of fixed/variable..julian)
824 	 */
825 	switch (st->density) {
826 /*      case 8 mm:   What is the SCSI density code for 8 mm, anyway? */
827 	case QIC_11:
828 	case QIC_24:
829 	case QIC_120:
830 	case QIC_150:
831 	case QIC_525:
832 	case QIC_1320:
833 		st->flags &= ~ST_2FM_AT_EOD;
834 		break;
835 	default:
836 		st->flags |= ST_2FM_AT_EOD;
837 	}
838 	return 0;
839 }
840 
841 /*
842  * trim the size of the transfer if needed,
843  * called by physio
844  * basically the smaller of our min and the scsi driver's
845  * minphys
846  */
847 void
848 stminphys(bp)
849 	struct buf *bp;
850 {
851 	register struct st_data *st = stcd.cd_devs[STUNIT(bp->b_dev)];
852 
853 	(st->sc_link->adapter->scsi_minphys) (bp);
854 }
855 
856 /*
857  * Actually translate the requested transfer into
858  * one the physical driver can understand
859  * The transfer is described by a buf and will include
860  * only one physical transfer.
861  */
862 void
863 ststrategy(bp)
864 	struct buf *bp;
865 {
866 	struct buf *dp;
867 	int unit;
868 	int opri;
869 	struct st_data *st;
870 
871 	unit = STUNIT(bp->b_dev);
872 	st = stcd.cd_devs[unit];
873 	SC_DEBUG(st->sc_link, SDEV_DB1,
874 	    ("ststrategy %d bytes @ blk %d\n", bp->b_bcount, bp->b_blkno));
875 	/*
876 	 * If it's a null transfer, return immediatly
877 	 */
878 	if (bp->b_bcount == 0) {
879 		goto done;
880 	}
881 	/*
882 	 * Odd sized request on fixed drives are verboten
883 	 */
884 	if (st->flags & ST_FIXEDBLOCKS) {
885 		if (bp->b_bcount % st->blksiz) {
886 			printf("%s: bad request, must be multiple of %d\n",
887 			    st->sc_dev.dv_xname, st->blksiz);
888 			bp->b_error = EIO;
889 			goto bad;
890 		}
891 	}
892 	/*
893 	 * as are out-of-range requests on variable drives.
894 	 */
895 	else if (bp->b_bcount < st->blkmin ||
896 		 (st->blkmax && bp->b_bcount > st->blkmax)) {
897 		printf("%s: bad request, must be between %d and %d\n",
898 		    st->sc_dev.dv_xname, st->blkmin, st->blkmax);
899 		bp->b_error = EIO;
900 		goto bad;
901 	}
902 	stminphys(bp);
903 	opri = splbio();
904 
905 	/*
906 	 * Place it in the queue of activities for this tape
907 	 * at the end (a bit silly because we only have on user..
908 	 * (but it could fork()))
909 	 */
910 	dp = &st->buf_queue;
911 	bp->b_actf = NULL;
912 	bp->b_actb = dp->b_actb;
913 	*dp->b_actb = bp;
914 	dp->b_actb = &bp->b_actf;
915 
916 	/*
917 	 * Tell the device to get going on the transfer if it's
918 	 * not doing anything, otherwise just wait for completion
919 	 * (All a bit silly if we're only allowing 1 open but..)
920 	 */
921 	ststart(unit);
922 
923 	splx(opri);
924 	return;
925 bad:
926 	bp->b_flags |= B_ERROR;
927 done:
928 	/*
929 	 * Correctly set the buf to indicate a completed xfer
930 	 */
931 	iodone(bp);
932 	return;
933 }
934 
935 /*
936  * ststart looks to see if there is a buf waiting for the device
937  * and that the device is not already busy. If both are true,
938  * It dequeues the buf and creates a scsi command to perform the
939  * transfer required. The transfer request will call scsi_done
940  * on completion, which will in turn call this routine again
941  * so that the next queued transfer is performed.
942  * The bufs are queued by the strategy routine (ststrategy)
943  *
944  * This routine is also called after other non-queued requests
945  * have been made of the scsi driver, to ensure that the queue
946  * continues to be drained.
947  * ststart() is called at splbio
948  */
949 void
950 ststart(unit)
951 	int unit;
952 {
953 	struct st_data *st = stcd.cd_devs[unit];
954 	struct scsi_link *sc_link = st->sc_link;
955 	register struct buf *bp, *dp;
956 	struct scsi_rw_tape cmd;
957 	int flags;
958 
959 	SC_DEBUG(sc_link, SDEV_DB2, ("ststart "));
960 	/*
961 	 * See if there is a buf to do and we are not already
962 	 * doing one
963 	 */
964 	while (sc_link->opennings) {
965 		/* if a special awaits, let it proceed first */
966 		if (sc_link->flags & SDEV_WAITING) {
967 			sc_link->flags &= ~SDEV_WAITING;
968 			wakeup((caddr_t)sc_link);
969 			return;
970 		}
971 
972 		bp = st->buf_queue.b_actf;
973 		if (!bp)
974 			return;	/* no work to bother with */
975 		if (dp = bp->b_actf)
976 			dp->b_actb = bp->b_actb;
977 		else
978 			st->buf_queue.b_actb = bp->b_actb;
979 		*bp->b_actb = dp;
980 
981 		/*
982 		 * if the device has been unmounted byt the user
983 		 * then throw away all requests until done
984 		 */
985 		if (!(st->flags & ST_MOUNTED) ||
986 		    !(sc_link->flags & SDEV_MEDIA_LOADED)) {
987 			/* make sure that one implies the other.. */
988 			sc_link->flags &= ~SDEV_MEDIA_LOADED;
989 			goto badnews;
990 		}
991 		/*
992 		 * only FIXEDBLOCK devices have pending operations
993 		 */
994 		if (st->flags & ST_FIXEDBLOCKS) {
995 			/*
996 			 * If we are at a filemark but have not reported it yet
997 			 * then we should report it now
998 			 */
999 			if (st->flags & ST_AT_FILEMARK) {
1000 				if ((bp->b_flags & B_READ) == B_WRITE) {
1001 					/*
1002 					 * Handling of ST_AT_FILEMARK in
1003 					 * st_space will fill in the right file
1004 					 * mark count.
1005 					 * Back up over filemark
1006 					 */
1007 					if (st_space(st, 0, SP_FILEMARKS, 0))
1008 						goto badnews;
1009 				} else {
1010 					bp->b_resid = bp->b_bcount;
1011 					bp->b_error = 0;
1012 					bp->b_flags &= ~B_ERROR;
1013 					st->flags &= ~ST_AT_FILEMARK;
1014 					biodone(bp);
1015 					continue;	/* seek more work */
1016 				}
1017 			}
1018 			/*
1019 			 * If we are at EIO (e.g. EOM) but have not reported it
1020 			 * yet then we should report it now
1021 			 */
1022 			if (st->flags & ST_EIO_PENDING) {
1023 				bp->b_resid = bp->b_bcount;
1024 				bp->b_error = EIO;
1025 				bp->b_flags |= B_ERROR;
1026 				st->flags &= ~ST_EIO_PENDING;
1027 				biodone(bp);
1028 				continue;	/* seek more work */
1029 			}
1030 		}
1031 
1032 		/*
1033 		 *  Fill out the scsi command
1034 		 */
1035 		bzero(&cmd, sizeof(cmd));
1036 		if ((bp->b_flags & B_READ) == B_WRITE) {
1037 			cmd.op_code = WRITE;
1038 			st->flags &= ~ST_FM_WRITTEN;
1039 			st->flags |= ST_WRITTEN;
1040 			flags = SCSI_DATA_OUT;
1041 		} else {
1042 			cmd.op_code = READ;
1043 			flags = SCSI_DATA_IN;
1044 		}
1045 
1046 		/*
1047 		 * Handle "fixed-block-mode" tape drives by using the
1048 		 * block count instead of the length.
1049 		 */
1050 		if (st->flags & ST_FIXEDBLOCKS) {
1051 			cmd.byte2 |= SRW_FIXED;
1052 			lto3b(bp->b_bcount / st->blksiz, cmd.len);
1053 		} else
1054 			lto3b(bp->b_bcount, cmd.len);
1055 
1056 		/*
1057 		 * go ask the adapter to do all this for us
1058 		 */
1059 		if (scsi_scsi_cmd(sc_link, (struct scsi_generic *) &cmd,
1060 		    sizeof(cmd), (u_char *) bp->b_un.b_addr, bp->b_bcount, 0,
1061 		    100000, bp, flags | SCSI_NOSLEEP) != SUCCESSFULLY_QUEUED) {
1062 badnews:
1063 			printf("%s: not queued\n", st->sc_dev.dv_xname);
1064 			bp->b_flags |= B_ERROR;
1065 			bp->b_error = EIO;
1066 			biodone(bp);
1067 		}
1068 	} /* go back and see if we can cram more work in.. */
1069 }
1070 
1071 /*
1072  * Perform special action on behalf of the user;
1073  * knows about the internals of this device
1074  */
1075 int
1076 stioctl(dev, cmd, arg, flag)
1077 	dev_t dev;
1078 	int cmd;
1079 	caddr_t arg;
1080 	int flag;
1081 {
1082 	int error = 0;
1083 	int unit;
1084 	int number, nmarks, dsty;
1085 	int flags;
1086 	struct st_data *st;
1087 	u_int hold_blksiz;
1088 	u_int hold_density;
1089 	struct mtop *mt = (struct mtop *) arg;
1090 
1091 	/*
1092 	 * Find the device that the user is talking about
1093 	 */
1094 	flags = 0;		/* give error messages, act on errors etc. */
1095 	unit = STUNIT(dev);
1096 	dsty = STDSTY(dev);
1097 	st = stcd.cd_devs[unit];
1098 	hold_blksiz = st->blksiz;
1099 	hold_density = st->density;
1100 
1101 	switch (cmd) {
1102 
1103 	case MTIOCGET: {
1104 		struct mtget *g = (struct mtget *) arg;
1105 
1106 		SC_DEBUG(st->sc_link, SDEV_DB1, ("[ioctl: get status]\n"));
1107 		bzero(g, sizeof(struct mtget));
1108 		g->mt_type = 0x7;	/* Ultrix compat *//*? */
1109 		g->mt_blksiz = st->blksiz;
1110 		g->mt_density = st->density;
1111 		g->mt_mblksiz[0] = st->modes[0].blksiz;
1112 		g->mt_mblksiz[1] = st->modes[1].blksiz;
1113 		g->mt_mblksiz[2] = st->modes[2].blksiz;
1114 		g->mt_mblksiz[3] = st->modes[3].blksiz;
1115 		g->mt_mdensity[0] = st->modes[0].density;
1116 		g->mt_mdensity[1] = st->modes[1].density;
1117 		g->mt_mdensity[2] = st->modes[2].density;
1118 		g->mt_mdensity[3] = st->modes[3].density;
1119 		break;
1120 	}
1121 	case MTIOCTOP: {
1122 
1123 		SC_DEBUG(st->sc_link, SDEV_DB1,
1124 		    ("[ioctl: op=0x%x count=0x%x]\n", mt->mt_op, mt->mt_count));
1125 
1126 		/* compat: in U*x it is a short */
1127 		number = mt->mt_count;
1128 		switch ((short) (mt->mt_op)) {
1129 		case MTWEOF:	/* write an end-of-file record */
1130 			error = st_write_filemarks(st, number, flags);
1131 			break;
1132 		case MTBSF:	/* backward space file */
1133 			number = -number;
1134 		case MTFSF:	/* forward space file */
1135 			error = st_check_eod(st, FALSE, &nmarks, flags);
1136 			if (!error)
1137 				error = st_space(st, number - nmarks,
1138 				    SP_FILEMARKS, flags);
1139 			break;
1140 		case MTBSR:	/* backward space record */
1141 			number = -number;
1142 		case MTFSR:	/* forward space record */
1143 			error = st_check_eod(st, TRUE, &nmarks, flags);
1144 			if (!error)
1145 				error = st_space(st, number, SP_BLKS, flags);
1146 			break;
1147 		case MTREW:	/* rewind */
1148 			error = st_rewind(st, 0, flags);
1149 			break;
1150 		case MTOFFL:	/* rewind and put the drive offline */
1151 			st_unmount(st, EJECT);
1152 			break;
1153 		case MTNOP:	/* no operation, sets status only */
1154 			break;
1155 		case MTRETEN:	/* retension the tape */
1156 			error = st_load(st, LD_RETENSION, flags);
1157 			if (!error)
1158 				error = st_load(st, LD_LOAD, flags);
1159 			break;
1160 		case MTEOM:	/* forward space to end of media */
1161 			error = st_check_eod(st, FALSE, &nmarks, flags);
1162 			if (!error)
1163 				error = st_space(st, 1, SP_EOM, flags);
1164 			break;
1165 		case MTCACHE:	/* enable controller cache */
1166 		case MTNOCACHE:	/* disable controller cache */
1167 			break;
1168 		case MTSETBSIZ:	/* Set block size for device */
1169 #ifdef	NOTYET
1170 			if (!(st->flags & ST_NEW_MOUNT)) {
1171 				uprintf("re-mount tape before changing blocksize");
1172 				error = EINVAL;
1173 				break;
1174 			}
1175 #endif
1176 			if (number == 0) {
1177 				st->flags &= ~ST_FIXEDBLOCKS;
1178 			} else {
1179 				if ((st->blkmin || st->blkmax) &&
1180 				    (number < st->blkmin ||
1181 				    number > st->blkmax)) {
1182 					error = EINVAL;
1183 					break;
1184 				}
1185 				st->flags |= ST_FIXEDBLOCKS;
1186 			}
1187 			st->blksiz = number;
1188 			st->flags |= ST_BLOCK_SET;	/*XXX */
1189 			goto try_new_value;
1190 
1191 		case MTSETDNSTY:	/* Set density for device and mode */
1192 			if (number > SCSI_2_MAX_DENSITY_CODE)
1193 				error = EINVAL;
1194 			else
1195 				st->density = number;
1196 			goto try_new_value;
1197 
1198 		default:
1199 			error = EINVAL;
1200 		}
1201 		break;
1202 	}
1203 	case MTIOCIEOT:
1204 	case MTIOCEEOT:
1205 		break;
1206 	default:
1207 		if (STMODE(dev) == CTLMODE)
1208 			error = scsi_do_ioctl(st->sc_link,cmd,arg,flag);
1209 		else
1210 			error = ENOTTY;
1211 		break;
1212 	}
1213 	return error;
1214 /*-----------------------------*/
1215 try_new_value:
1216 	/*
1217 	 * Check that the mode being asked for is aggreeable to the
1218 	 * drive. If not, put it back the way it was.
1219 	 */
1220 	if (error = st_mode_select(st, 0)) {	/* put it back as it was */
1221 		printf("%s: cannot set selected mode\n", st->sc_dev.dv_xname);
1222 		st->density = hold_density;
1223 		st->blksiz = hold_blksiz;
1224 		if (st->blksiz)
1225 			st->flags |= ST_FIXEDBLOCKS;
1226 		else
1227 			st->flags &= ~ST_FIXEDBLOCKS;
1228 		return error;
1229 	}
1230 	/*
1231 	 * As the drive liked it, if we are setting a new default,
1232 	 * set it into the structures as such.
1233 	 *
1234 	 * The means for deciding this are not finalised yet
1235 	 */
1236 	if (STMODE(dev) == 0x03) {
1237 		/* special mode */
1238 		/* XXX */
1239 		switch ((short) (mt->mt_op)) {
1240 		case MTSETBSIZ:
1241 			st->modes[dsty].blksiz = st->blksiz;
1242 			st->modeflags[dsty] |= BLKSIZE_SET_BY_USER;
1243 			break;
1244 		case MTSETDNSTY:
1245 			st->modes[dsty].density = st->density;
1246 			st->modeflags[dsty] |= DENSITY_SET_BY_USER;
1247 			break;
1248 		}
1249 	}
1250 	return 0;
1251 }
1252 
1253 /*
1254  * Do a synchronous read.
1255  */
1256 int
1257 st_read(st, buf, size, flags)
1258 	struct st_data *st;
1259 	u_int size;
1260 	int flags;
1261 	char *buf;
1262 {
1263 	struct scsi_rw_tape cmd;
1264 
1265 	/*
1266 	 * If it's a null transfer, return immediatly
1267 	 */
1268 	if (size == 0)
1269 		return 0;
1270 	bzero(&cmd, sizeof(cmd));
1271 	cmd.op_code = READ;
1272 	if (st->flags & ST_FIXEDBLOCKS) {
1273 		cmd.byte2 |= SRW_FIXED;
1274 		lto3b(size / (st->blksiz ? st->blksiz : DEF_FIXED_BSIZE),
1275 		    cmd.len);
1276 	} else
1277 		lto3b(size, cmd.len);
1278 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1279 	    sizeof(cmd), (u_char *) buf, size, 0, 100000, NULL,
1280 	    flags | SCSI_DATA_IN);
1281 }
1282 
1283 #ifdef	__STDC__
1284 #define b2tol(a)	(((unsigned)(a##_1) << 8) + (unsigned)a##_0)
1285 #else
1286 #define b2tol(a)	(((unsigned)(a/**/_1) << 8) + (unsigned)a/**/_0)
1287 #endif
1288 
1289 /*
1290  * Ask the drive what it's min and max blk sizes are.
1291  */
1292 int
1293 st_read_block_limits(st, flags)
1294 	struct st_data *st;
1295 	int flags;
1296 {
1297 	struct scsi_block_limits cmd;
1298 	struct scsi_block_limits_data block_limits;
1299 	struct scsi_link *sc_link = st->sc_link;
1300 	int error;
1301 
1302 	/*
1303 	 * First check if we have it all loaded
1304 	 */
1305 	if ((sc_link->flags & SDEV_MEDIA_LOADED))
1306 		return 0;
1307 
1308 	/*
1309 	 * do a 'Read Block Limits'
1310 	 */
1311 	bzero(&cmd, sizeof(cmd));
1312 	cmd.op_code = READ_BLOCK_LIMITS;
1313 
1314 	/*
1315 	 * do the command, update the global values
1316 	 */
1317 	if (error = scsi_scsi_cmd(sc_link, (struct scsi_generic *) &cmd,
1318 	    sizeof(cmd), (u_char *) &block_limits, sizeof(block_limits),
1319 	    ST_RETRIES, 5000, NULL, flags | SCSI_DATA_IN))
1320 		return error;
1321 
1322 	st->blkmin = b2tol(block_limits.min_length);
1323 	st->blkmax = _3btol(&block_limits.max_length_2);
1324 
1325 	SC_DEBUG(sc_link, SDEV_DB3,
1326 	    ("(%d <= blksiz <= %d)\n", st->blkmin, st->blkmax));
1327 	return 0;
1328 }
1329 
1330 /*
1331  * Get the scsi driver to send a full inquiry to the
1332  * device and use the results to fill out the global
1333  * parameter structure.
1334  *
1335  * called from:
1336  * attach
1337  * open
1338  * ioctl (to reset original blksize)
1339  */
1340 int
1341 st_mode_sense(st, flags)
1342 	struct st_data *st;
1343 	int flags;
1344 {
1345 	u_int scsi_sense_len;
1346 	int error;
1347 	char *scsi_sense_ptr;
1348 	struct scsi_mode_sense cmd;
1349 	struct scsi_sense {
1350 		struct scsi_mode_header header;
1351 		struct blk_desc blk_desc;
1352 	} scsi_sense;
1353 
1354 	struct scsi_sense_page_0 {
1355 		struct scsi_mode_header header;
1356 		struct blk_desc blk_desc;
1357 		u_char sense_data[PAGE_0_SENSE_DATA_SIZE];
1358 			/* Tandberg tape drives returns page 00
1359 			 * with the sense data, whether or not
1360 			 * you want it (ie the don't like you
1361 			 * saying you want anything less!!!!!)
1362 			 * They also expect page 00
1363 			 * back when you issue a mode select
1364 			 */
1365 	} scsi_sense_page_0;
1366 	struct scsi_link *sc_link = st->sc_link;
1367 
1368 	/*
1369 	 * Define what sort of structure we're working with
1370 	 */
1371 	if (st->quirks & ST_Q_NEEDS_PAGE_0) {
1372 		scsi_sense_len = sizeof(scsi_sense_page_0);
1373 		scsi_sense_ptr = (char *) &scsi_sense_page_0;
1374 	} else {
1375 		scsi_sense_len = sizeof(scsi_sense);
1376 		scsi_sense_ptr = (char *) &scsi_sense;
1377 	}
1378 	/*
1379 	 * Set up a mode sense
1380 	 */
1381 	bzero(&cmd, sizeof(cmd));
1382 	cmd.op_code = MODE_SENSE;
1383 	cmd.length = scsi_sense_len;
1384 
1385 	/*
1386 	 * do the command, but we don't need the results
1387 	 * just print them for our interest's sake, if asked,
1388 	 * or if we need it as a template for the mode select
1389 	 * store it away.
1390 	 */
1391 	if (error = scsi_scsi_cmd(sc_link, (struct scsi_generic *) &cmd,
1392 	    sizeof(cmd), (u_char *) scsi_sense_ptr, scsi_sense_len,
1393 	    ST_RETRIES, 5000, NULL, flags | SCSI_DATA_IN))
1394 		return error;
1395 
1396 	st->numblks = _3btol(((struct scsi_sense *)scsi_sense_ptr)->blk_desc.nblocks);
1397 	st->media_blksiz = _3btol(((struct scsi_sense *)scsi_sense_ptr)->blk_desc.blklen);
1398 	st->media_density = ((struct scsi_sense *) scsi_sense_ptr)->blk_desc.density;
1399 	if (((struct scsi_sense *) scsi_sense_ptr)->header.dev_spec &
1400 	    SMH_DSP_WRITE_PROT)
1401 		st->flags |= ST_READONLY;
1402 	SC_DEBUG(sc_link, SDEV_DB3,
1403 	    ("density code 0x%x, %d-byte blocks, write-%s, ",
1404 	    st->media_density, st->media_blksiz,
1405 	    st->flags & ST_READONLY ? "protected" : "enabled"));
1406 	SC_DEBUG(sc_link, SDEV_DB3,
1407 	    ("%sbuffered\n",
1408 	    ((struct scsi_sense *) scsi_sense_ptr)->header.dev_spec &
1409 	    SMH_DSP_BUFF_MODE ? "" : "un"));
1410 	if (st->quirks & ST_Q_NEEDS_PAGE_0)
1411 		bcopy(((struct scsi_sense_page_0 *) scsi_sense_ptr)->sense_data,
1412 		    st->sense_data,
1413 		    sizeof(((struct scsi_sense_page_0 *) scsi_sense_ptr)->sense_data));
1414 	sc_link->flags |= SDEV_MEDIA_LOADED;
1415 	return 0;
1416 }
1417 
1418 /*
1419  * Send a filled out parameter structure to the drive to
1420  * set it into the desire modes etc.
1421  */
1422 int
1423 st_mode_select(st, flags)
1424 	struct st_data *st;
1425 	int flags;
1426 {
1427 	u_int dat_len;
1428 	char *dat_ptr;
1429 	struct scsi_mode_select cmd;
1430 	struct dat {
1431 		struct scsi_mode_header header;
1432 		struct blk_desc blk_desc;
1433 	} dat;
1434 	struct dat_page_0 {
1435 		struct scsi_mode_header header;
1436 		struct blk_desc blk_desc;
1437 		u_char sense_data[PAGE_0_SENSE_DATA_SIZE];
1438 	} dat_page_0;
1439 
1440 	/*
1441 	 * Define what sort of structure we're working with
1442 	 */
1443 	if (st->quirks & ST_Q_NEEDS_PAGE_0) {
1444 		dat_len = sizeof(dat_page_0);
1445 		dat_ptr = (char *) &dat_page_0;
1446 	} else {
1447 		dat_len = sizeof(dat);
1448 		dat_ptr = (char *) &dat;
1449 	}
1450 	/*
1451 	 * Set up for a mode select
1452 	 */
1453 	bzero(&cmd, sizeof(cmd));
1454 	cmd.op_code = MODE_SELECT;
1455 	cmd.length = dat_len;
1456 
1457 	bzero(dat_ptr, dat_len);
1458 	((struct dat *) dat_ptr)->header.blk_desc_len = sizeof(struct blk_desc);
1459 	((struct dat *) dat_ptr)->header.dev_spec |= SMH_DSP_BUFF_MODE_ON;
1460 	((struct dat *) dat_ptr)->blk_desc.density = st->density;
1461 	if (st->flags & ST_FIXEDBLOCKS)
1462 		lto3b(st->blksiz, ((struct dat *) dat_ptr)->blk_desc.blklen);
1463 	if (st->quirks & ST_Q_NEEDS_PAGE_0) {
1464 		bcopy(st->sense_data,
1465 		    ((struct dat_page_0 *) dat_ptr)->sense_data,
1466 		    sizeof(((struct dat_page_0 *) dat_ptr)->sense_data));
1467 		/* the Tandberg tapes need the block size to */
1468 		/* be set on each mode sense/select. */
1469 	}
1470 
1471 	/*
1472 	 * do the command
1473 	 */
1474 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1475 	    sizeof(cmd), (u_char *) dat_ptr, dat_len, ST_RETRIES, 5000,
1476 	    NULL, flags | SCSI_DATA_OUT);
1477 }
1478 
1479 /*
1480  * skip N blocks/filemarks/seq filemarks/eom
1481  */
1482 int
1483 st_space(st, number, what, flags)
1484 	struct st_data *st;
1485 	u_int what;
1486 	int flags;
1487 	int number;
1488 {
1489 	struct scsi_space cmd;
1490 	int error;
1491 
1492 	switch (what) {
1493 	case SP_BLKS:
1494 		if (st->flags & ST_PER_ACTION) {
1495 			if (number > 0) {
1496 				st->flags &= ~ST_PER_ACTION;
1497 				return EIO;
1498 			} else if (number < 0) {
1499 				if (st->flags & ST_AT_FILEMARK) {
1500 					/*
1501 					 * Handling of ST_AT_FILEMARK
1502 					 * in st_space will fill in the
1503 					 * right file mark count.
1504 					 */
1505 					error = st_space(st, 0, SP_FILEMARKS,
1506 						flags);
1507 					if (error)
1508 						return error;
1509 				}
1510 				if (st->flags & ST_BLANK_READ) {
1511 					st->flags &= ~ST_BLANK_READ;
1512 					return EIO;
1513 				}
1514 				st->flags &= ~ST_EIO_PENDING;
1515 			}
1516 		}
1517 		break;
1518 	case SP_FILEMARKS:
1519 		if (st->flags & ST_EIO_PENDING) {
1520 			if (number > 0) {
1521 				/* pretend we just discovered the error */
1522 				st->flags &= ~ST_EIO_PENDING;
1523 				return EIO;
1524 			} else if (number < 0) {
1525 				/* back away from the error */
1526 				st->flags &= ~ST_EIO_PENDING;
1527 			}
1528 		}
1529 		if (st->flags & ST_AT_FILEMARK) {
1530 			st->flags &= ~ST_AT_FILEMARK;
1531 			number--;
1532 		}
1533 		if ((st->flags & ST_BLANK_READ) && (number < 0)) {
1534 			/* back away from unwritten tape */
1535 			st->flags &= ~ST_BLANK_READ;
1536 			number++;	/* XXX dubious */
1537 		}
1538 		break;
1539 	case SP_EOM:
1540 		if (st->flags & ST_EIO_PENDING) {
1541 			/* pretend we just discovered the error */
1542 			st->flags &= ~ST_EIO_PENDING;
1543 			return EIO;
1544 		}
1545 		if (st->flags & ST_AT_FILEMARK)
1546 			st->flags &= ~ST_AT_FILEMARK;
1547 		break;
1548 	}
1549 	if (number == 0)
1550 		return 0;
1551 
1552 	bzero(&cmd, sizeof(cmd));
1553 	cmd.op_code = SPACE;
1554 	cmd.byte2 = what;
1555 	lto3b(number, cmd.number);
1556 
1557 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1558 	    sizeof(cmd), 0, 0, 0, 600000, NULL, flags);
1559 }
1560 
1561 /*
1562  * write N filemarks
1563  */
1564 int
1565 st_write_filemarks(st, number, flags)
1566 	struct st_data *st;
1567 	int flags;
1568 	int number;
1569 {
1570 	struct scsi_write_filemarks cmd;
1571 
1572 	/*
1573 	 * It's hard to write a negative number of file marks.
1574 	 * Don't try.
1575 	 */
1576 	if (number < 0)
1577 		return EINVAL;
1578 	switch (number) {
1579 	case 0:		/* really a command to sync the drive's buffers */
1580 		break;
1581 	case 1:
1582 		if (st->flags & ST_FM_WRITTEN)	/* already have one down */
1583 			st->flags &= ~ST_WRITTEN;
1584 		else
1585 			st->flags |= ST_FM_WRITTEN;
1586 		st->flags &= ~ST_PER_ACTION;
1587 		break;
1588 	default:
1589 		st->flags &= ~(ST_PER_ACTION | ST_WRITTEN);
1590 	}
1591 
1592 	bzero(&cmd, sizeof(cmd));
1593 	cmd.op_code = WRITE_FILEMARKS;
1594 	lto3b(number, cmd.number);
1595 
1596 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1597 	    sizeof(cmd), 0, 0, 0, 100000, NULL, flags);
1598 }
1599 
1600 /*
1601  * Make sure the right number of file marks is on tape if the
1602  * tape has been written.  If the position argument is true,
1603  * leave the tape positioned where it was originally.
1604  *
1605  * nmarks returns the number of marks to skip (or, if position
1606  * true, which were skipped) to get back original position.
1607  */
1608 int
1609 st_check_eod(st, position, nmarks, flags)
1610 	struct st_data *st;
1611 	boolean position;
1612 	int *nmarks;
1613 	int flags;
1614 {
1615 	int error;
1616 
1617 	switch (st->flags & (ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD)) {
1618 	default:
1619 		*nmarks = 0;
1620 		return 0;
1621 	case ST_WRITTEN:
1622 	case ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD:
1623 		*nmarks = 1;
1624 		break;
1625 	case ST_WRITTEN | ST_2FM_AT_EOD:
1626 		*nmarks = 2;
1627 	}
1628 	error = st_write_filemarks(st, *nmarks, flags);
1629 	if (position && !error)
1630 		error = st_space(st, -*nmarks, SP_FILEMARKS, flags);
1631 	return error;
1632 }
1633 
1634 /*
1635  * load/unload/retension
1636  */
1637 int
1638 st_load(st, type, flags)
1639 	struct st_data *st;
1640 	u_int type;
1641 	int flags;
1642 {
1643 	struct scsi_load cmd;
1644 
1645 	if (type != LD_LOAD) {
1646 		int error;
1647 		int nmarks;
1648 
1649 		error = st_check_eod(st, FALSE, &nmarks, flags);
1650 		if (error)
1651 			return error;
1652 	}
1653 	if (st->quirks & ST_Q_IGNORE_LOADS)
1654 		return 0;
1655 
1656 	bzero(&cmd, sizeof(cmd));
1657 	cmd.op_code = LOAD;
1658 	cmd.how = type;
1659 
1660 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1661 	    sizeof(cmd), 0, 0, ST_RETRIES, 300000, NULL, flags);
1662 }
1663 
1664 /*
1665  *  Rewind the device
1666  */
1667 int
1668 st_rewind(st, immediate, flags)
1669 	struct st_data *st;
1670 	u_int immediate;
1671 	int flags;
1672 {
1673 	struct scsi_rewind cmd;
1674 	int error;
1675 	int nmarks;
1676 
1677 	error = st_check_eod(st, FALSE, &nmarks, flags);
1678 	if (error)
1679 		return error;
1680 	st->flags &= ~ST_PER_ACTION;
1681 
1682 	bzero(&cmd, sizeof(cmd));
1683 	cmd.op_code = REWIND;
1684 	cmd.byte2 = immediate;
1685 
1686 	return scsi_scsi_cmd(st->sc_link, (struct scsi_generic *) &cmd,
1687 	    sizeof(cmd), 0, 0, ST_RETRIES, immediate ? 5000 : 300000, NULL,
1688 	    flags);
1689 }
1690 
1691 /*
1692  * Look at the returned sense and act on the error and detirmine
1693  * The unix error number to pass back... (0 = report no error)
1694  *                            (-1 = continue processing)
1695  */
1696 int
1697 st_interpret_sense(xs)
1698 	struct scsi_xfer *xs;
1699 {
1700 	struct scsi_link *sc_link = xs->sc_link;
1701 	struct scsi_sense_data *sense = &xs->sense;
1702 	boolean silent = xs->flags & SCSI_SILENT;
1703 	struct buf *bp = xs->bp;
1704 	int unit = sc_link->dev_unit;
1705 	struct st_data *st = stcd.cd_devs[unit];
1706 	u_int key;
1707 	int info;
1708 
1709 	/*
1710 	 * Get the sense fields and work out what code
1711 	 */
1712 	if (sense->error_code & SSD_ERRCODE_VALID)
1713 		info = ntohl(*((int *) sense->extended_info));
1714 	else
1715 		info = xs->datalen;	/* bad choice if fixed blocks */
1716 	if ((sense->error_code & SSD_ERRCODE) != 0x70)
1717 		return -1;	/* let the generic code handle it */
1718 	if (st->flags & ST_FIXEDBLOCKS) {
1719 		xs->resid = info * st->blksiz;
1720 		if (sense->extended_flags & SSD_EOM) {
1721 			st->flags |= ST_EIO_PENDING;
1722 			if (bp)
1723 				bp->b_resid = xs->resid;
1724 		}
1725 		if (sense->extended_flags & SSD_FILEMARK) {
1726 			st->flags |= ST_AT_FILEMARK;
1727 			if (bp)
1728 				bp->b_resid = xs->resid;
1729 		}
1730 		if (sense->extended_flags & SSD_ILI) {
1731 			st->flags |= ST_EIO_PENDING;
1732 			if (bp)
1733 				bp->b_resid = xs->resid;
1734 			if (sense->error_code & SSD_ERRCODE_VALID && !silent)
1735 				printf("%s: block wrong size, %d blocks residual\n",
1736 				    st->sc_dev.dv_xname, info);
1737 
1738 			/*
1739 			 * This quirk code helps the drive read
1740 			 * the first tape block, regardless of
1741 			 * format.  That is required for these
1742 			 * drives to return proper MODE SENSE
1743 			 * information.
1744 			 */
1745 			if ((st->quirks & ST_Q_SENSE_HELP) &&
1746 			    !(sc_link->flags & SDEV_MEDIA_LOADED))
1747 				st->blksiz -= 512;
1748 		}
1749 		/*
1750 		 * If no data was tranfered, do it immediatly
1751 		 */
1752 		if (xs->resid >= xs->datalen) {
1753 			if (st->flags & ST_EIO_PENDING)
1754 				return EIO;
1755 			if (st->flags & ST_AT_FILEMARK) {
1756 				if (bp)
1757 					bp->b_resid = xs->resid;
1758 				return 0;
1759 			}
1760 		}
1761 	} else {		/* must be variable mode */
1762 		xs->resid = xs->datalen;	/* to be sure */
1763 		if (sense->extended_flags & SSD_EOM)
1764 			return EIO;
1765 		if (sense->extended_flags & SSD_FILEMARK) {
1766 			if (bp)
1767 				bp->b_resid = bp->b_bcount;
1768 			return 0;
1769 		}
1770 		if (sense->extended_flags & SSD_ILI) {
1771 			if (info < 0) {
1772 				/*
1773 				 * the record was bigger than the read
1774 				 */
1775 				if (!silent)
1776 					printf("%s: %d-byte record too big\n",
1777 					    st->sc_dev.dv_xname,
1778 					    xs->datalen - info);
1779 				return EIO;
1780 			}
1781 			xs->resid = info;
1782 			if (bp)
1783 				bp->b_resid = info;
1784 		}
1785 	}
1786 	key = sense->extended_flags & SSD_KEY;
1787 
1788 	if (key == 0x8) {
1789 		/*
1790 		 * This quirk code helps the drive read the
1791 		 * first tape block, regardless of format.  That
1792 		 * is required for these drives to return proper
1793 		 * MODE SENSE information.
1794 		 */
1795 		if ((st->quirks & ST_Q_SENSE_HELP) &&
1796 		    !(sc_link->flags & SDEV_MEDIA_LOADED)) {
1797 			/* still starting */
1798 			st->blksiz -= 512;
1799 		} else if (!(st->flags & (ST_2FM_AT_EOD | ST_BLANK_READ))) {
1800 			st->flags |= ST_BLANK_READ;
1801 			xs->resid = xs->datalen;
1802 			if (bp) {
1803 				bp->b_resid = xs->resid;
1804 				/* return an EOF */
1805 			}
1806 			return 0;
1807 		}
1808 	}
1809 	return -1;		/* let the default/generic handler handle it */
1810 }
1811 
1812 /*
1813  * The quirk here is that the drive returns some value to st_mode_sense
1814  * incorrectly until the tape has actually passed by the head.
1815  *
1816  * The method is to set the drive to large fixed-block state (user-specified
1817  * density and 1024-byte blocks), then read and rewind to get it to sense the
1818  * tape.  If that doesn't work, try 512-byte fixed blocks.  If that doesn't
1819  * work, as a last resort, try variable- length blocks.  The result will be
1820  * the ability to do an accurate st_mode_sense.
1821  *
1822  * We know we can do a rewind because we just did a load, which implies rewind.
1823  * Rewind seems preferable to space backward if we have a virgin tape.
1824  *
1825  * The rest of the code for this quirk is in ILI processing and BLANK CHECK
1826  * error processing, both part of st_interpret_sense.
1827  */
1828 int
1829 st_touch_tape(st)
1830 	struct st_data *st;
1831 {
1832 	char   *buf;
1833 	u_int readsiz;
1834 	int error;
1835 
1836 	buf = malloc(1024, M_TEMP, M_NOWAIT);
1837 	if (!buf)
1838 		return ENOMEM;
1839 
1840 	if (error = st_mode_sense(st, 0))
1841 		goto bad;
1842 	st->blksiz = 1024;
1843 	do {
1844 		switch (st->blksiz) {
1845 		case 512:
1846 		case 1024:
1847 			readsiz = st->blksiz;
1848 			st->flags |= ST_FIXEDBLOCKS;
1849 			break;
1850 		default:
1851 			readsiz = 1;
1852 			st->flags &= ~ST_FIXEDBLOCKS;
1853 		}
1854 		if (error = st_mode_select(st, 0))
1855 			goto bad;
1856 		st_read(st, buf, readsiz, SCSI_SILENT);
1857 		if (error = st_rewind(st, 0, 0)) {
1858 bad:			free(buf, M_TEMP);
1859 			return error;
1860 		}
1861 	} while (readsiz != 1 && readsiz > st->blksiz);
1862 	free(buf, M_TEMP);
1863 	return 0;
1864 }
1865 
1866 int
1867 stdump()
1868 {
1869 
1870 	/* Not implemented. */
1871 	return EINVAL;
1872 }
1873