xref: /netbsd-src/sys/dev/scsipi/st.c (revision 2c6fc41c810f5088457889d00eba558e8bc74d9e)
1 /*	$NetBSD: st.c,v 1.223 2014/03/16 05:20:29 dholland Exp $ */
2 
3 /*-
4  * Copyright (c) 1998, 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
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  * A lot of rewhacking done by mjacob (mjacob@nas.nasa.gov).
50  */
51 
52 #include <sys/cdefs.h>
53 __KERNEL_RCSID(0, "$NetBSD: st.c,v 1.223 2014/03/16 05:20:29 dholland Exp $");
54 
55 #include "opt_scsi.h"
56 
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/bufq.h>
65 #include <sys/proc.h>
66 #include <sys/mtio.h>
67 #include <sys/device.h>
68 #include <sys/conf.h>
69 #include <sys/kernel.h>
70 #include <sys/vnode.h>
71 #include <sys/iostat.h>
72 #include <sys/sysctl.h>
73 
74 #include <dev/scsipi/scsi_spc.h>
75 #include <dev/scsipi/scsipi_all.h>
76 #include <dev/scsipi/scsi_all.h>
77 #include <dev/scsipi/scsi_tape.h>
78 #include <dev/scsipi/scsipiconf.h>
79 #include <dev/scsipi/scsipi_base.h>
80 #include <dev/scsipi/stvar.h>
81 
82 /* Defines for device specific stuff */
83 #define DEF_FIXED_BSIZE  512
84 
85 #define STMODE(z)	( minor(z)       & 0x03)
86 #define STDSTY(z)	((minor(z) >> 2) & 0x03)
87 #define STUNIT(z)	((minor(z) >> 4)       )
88 #define STNMINOR	16
89 
90 #define NORMAL_MODE	0
91 #define NOREW_MODE	1
92 #define EJECT_MODE	2
93 #define CTRL_MODE	3
94 
95 #ifndef		ST_MOUNT_DELAY
96 #define		ST_MOUNT_DELAY		0
97 #endif
98 
99 static dev_type_open(stopen);
100 static dev_type_close(stclose);
101 static dev_type_read(stread);
102 static dev_type_write(stwrite);
103 static dev_type_ioctl(stioctl);
104 static dev_type_strategy(ststrategy);
105 static dev_type_dump(stdump);
106 
107 const struct bdevsw st_bdevsw = {
108 	.d_open = stopen,
109 	.d_close = stclose,
110 	.d_strategy = ststrategy,
111 	.d_ioctl = stioctl,
112 	.d_dump = stdump,
113 	.d_psize = nosize,
114 	.d_flag = D_TAPE
115 };
116 
117 const struct cdevsw st_cdevsw = {
118 	.d_open = stopen,
119 	.d_close = stclose,
120 	.d_read = stread,
121 	.d_write = stwrite,
122 	.d_ioctl = stioctl,
123 	.d_stop = nostop,
124 	.d_tty = notty,
125 	.d_poll = nopoll,
126 	.d_mmap = nommap,
127 	.d_kqfilter = nokqfilter,
128 	.d_flag = D_TAPE
129 };
130 
131 /*
132  * Define various devices that we know mis-behave in some way,
133  * and note how they are bad, so we can correct for them
134  */
135 
136 static const struct st_quirk_inquiry_pattern st_quirk_patterns[] = {
137 	{{T_SEQUENTIAL, T_REMOV,
138 	 "        ", "                ", "    "}, {0, 0, {
139 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
140 		{ST_Q_FORCE_BLKSIZE, 512, QIC_24},	/* minor 4-7 */
141 		{ST_Q_FORCE_BLKSIZE, 0, HALFINCH_1600},	/* minor 8-11 */
142 		{ST_Q_FORCE_BLKSIZE, 0, HALFINCH_6250}	/* minor 12-15 */
143 	}}},
144 	{{T_SEQUENTIAL, T_REMOV,
145 	 "TANDBERG", " TDC 3600       ", ""},     {0, 12, {
146 		{0, 0, 0},				/* minor 0-3 */
147 		{ST_Q_FORCE_BLKSIZE, 0, QIC_525},	/* minor 4-7 */
148 		{0, 0, QIC_150},			/* minor 8-11 */
149 		{0, 0, QIC_120}				/* minor 12-15 */
150 	}}},
151  	{{T_SEQUENTIAL, T_REMOV,
152  	 "TANDBERG", " TDC 3800       ", ""},     {0, 0, {
153 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
154 		{0, 0, QIC_525},			/* minor 4-7 */
155 		{0, 0, QIC_150},			/* minor 8-11 */
156 		{0, 0, QIC_120}				/* minor 12-15 */
157 	}}},
158 	{{T_SEQUENTIAL, T_REMOV,
159 	  "TANDBERG", " SLR5 4/8GB     ", ""},     {0, 0, {
160 		{ST_Q_FORCE_BLKSIZE, 1024, 0},		/* minor 0-3 */
161 		{0, 0, 0},				/* minor 4-7 */
162 		{0, 0, 0},				/* minor 8-11 */
163 		{0, 0, 0}				/* minor 12-15 */
164 	}}},
165 	/*
166 	 * lacking a manual for the 4200, it's not clear what the
167 	 * specific density codes should be- the device is a 2.5GB
168 	 * capable QIC drive, those density codes aren't readily
169 	 * availabel. The 'default' will just have to do.
170 	 */
171  	{{T_SEQUENTIAL, T_REMOV,
172  	 "TANDBERG", " TDC 4200       ", ""},     {0, 0, {
173 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
174 		{0, 0, QIC_525},			/* minor 4-7 */
175 		{0, 0, QIC_150},			/* minor 8-11 */
176 		{0, 0, QIC_120}				/* minor 12-15 */
177 	}}},
178 	/*
179 	 * At least -005 and -007 need this.  I'll assume they all do unless I
180 	 * hear otherwise.  - mycroft, 31MAR1994
181 	 */
182 	{{T_SEQUENTIAL, T_REMOV,
183 	 "ARCHIVE ", "VIPER 2525 25462", ""},     {0, 0, {
184 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
185 		{ST_Q_SENSE_HELP, 0, QIC_525},		/* minor 4-7 */
186 		{0, 0, QIC_150},			/* minor 8-11 */
187 		{0, 0, QIC_120}				/* minor 12-15 */
188 	}}},
189 	/*
190 	 * One user reports that this works for his tape drive.  It probably
191 	 * needs more work.  - mycroft, 09APR1994
192 	 */
193 	{{T_SEQUENTIAL, T_REMOV,
194 	 "SANKYO  ", "CP525           ", ""},    {0, 0, {
195 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
196 		{ST_Q_FORCE_BLKSIZE, 512, QIC_525},	/* minor 4-7 */
197 		{0, 0, QIC_150},			/* minor 8-11 */
198 		{0, 0, QIC_120}				/* minor 12-15 */
199 	}}},
200 	{{T_SEQUENTIAL, T_REMOV,
201 	 "ANRITSU ", "DMT780          ", ""},     {0, 0, {
202 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
203 		{ST_Q_FORCE_BLKSIZE, 512, QIC_525},	/* minor 4-7 */
204 		{0, 0, QIC_150},			/* minor 8-11 */
205 		{0, 0, QIC_120}				/* minor 12-15 */
206 	}}},
207 	{{T_SEQUENTIAL, T_REMOV,
208 	 "ARCHIVE ", "VIPER 150  21247", ""},     {ST_Q_ERASE_NOIMM, 12, {
209 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
210 		{0, 0, QIC_150},			/* minor 4-7 */
211 		{0, 0, QIC_120},			/* minor 8-11 */
212 		{0, 0, QIC_24}				/* minor 12-15 */
213 	}}},
214 	{{T_SEQUENTIAL, T_REMOV,
215 	 "ARCHIVE ", "VIPER 150  21531", ""},     {ST_Q_ERASE_NOIMM, 12, {
216 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
217 		{0, 0, QIC_150},			/* minor 4-7 */
218 		{0, 0, QIC_120},			/* minor 8-11 */
219 		{0, 0, QIC_24}				/* minor 12-15 */
220 	}}},
221 	{{T_SEQUENTIAL, T_REMOV,
222 	 "WANGTEK ", "5099ES SCSI", ""},          {0, 0, {
223 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
224 		{0, 0, QIC_11},				/* minor 4-7 */
225 		{0, 0, QIC_24},				/* minor 8-11 */
226 		{0, 0, QIC_24}				/* minor 12-15 */
227 	}}},
228 	{{T_SEQUENTIAL, T_REMOV,
229 	 "WANGTEK ", "5150ES SCSI", ""},          {0, 0, {
230 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
231 		{0, 0, QIC_24},				/* minor 4-7 */
232 		{0, 0, QIC_120},			/* minor 8-11 */
233 		{0, 0, QIC_150}				/* minor 12-15 */
234 	}}},
235 	{{T_SEQUENTIAL, T_REMOV,
236 	 "WANGTEK ", "5525ES SCSI REV7", ""},     {0, 0, {
237 		{0, 0, 0},				/* minor 0-3 */
238 		{ST_Q_BLKSIZE, 0, QIC_525},		/* minor 4-7 */
239 		{0, 0, QIC_150},			/* minor 8-11 */
240 		{0, 0, QIC_120}				/* minor 12-15 */
241 	}}},
242 	{{T_SEQUENTIAL, T_REMOV,
243 	 "WangDAT ", "Model 1300      ", ""},     {0, 0, {
244 		{0, 0, 0},				/* minor 0-3 */
245 		{ST_Q_FORCE_BLKSIZE, 512, DDS},		/* minor 4-7 */
246 		{ST_Q_FORCE_BLKSIZE, 1024, DDS},	/* minor 8-11 */
247 		{ST_Q_FORCE_BLKSIZE, 0, DDS}		/* minor 12-15 */
248 	}}},
249 	{{T_SEQUENTIAL, T_REMOV,
250 	 "EXABYTE ", "EXB-8200        ", "263H"}, {0, 5, {
251 		{0, 0, 0},				/* minor 0-3 */
252 		{0, 0, 0},				/* minor 4-7 */
253 		{0, 0, 0},				/* minor 8-11 */
254 		{0, 0, 0}				/* minor 12-15 */
255 	}}},
256 	{{T_SEQUENTIAL, T_REMOV,
257 	 "STK",      "9490",             ""},
258 				{ST_Q_FORCE_BLKSIZE, 0, {
259 		{0, 0, 0},				/* minor 0-3 */
260 		{0, 0, 0},				/* minor 4-7 */
261 		{0, 0, 0},				/* minor 8-11 */
262 		{0, 0, 0}				/* minor 12-15 */
263 	}}},
264 	{{T_SEQUENTIAL, T_REMOV,
265 	 "STK",      "SD-3",             ""},
266 				{ST_Q_FORCE_BLKSIZE, 0, {
267 		{0, 0, 0},				/* minor 0-3 */
268 		{0, 0, 0},				/* minor 4-7 */
269 		{0, 0, 0},				/* minor 8-11 */
270 		{0, 0, 0}				/* minor 12-15 */
271 	}}},
272 	{{T_SEQUENTIAL, T_REMOV,
273 	 "IBM",      "03590",            ""},     {ST_Q_IGNORE_LOADS, 0, {
274 		{0, 0, 0},				/* minor 0-3 */
275 		{0, 0, 0},				/* minor 4-7 */
276 		{0, 0, 0},				/* minor 8-11 */
277 		{0, 0, 0}				/* minor 12-15 */
278 	}}},
279 	{{T_SEQUENTIAL, T_REMOV,
280 	 "HP      ", "T4000s          ", ""},     {ST_Q_UNIMODAL, 0, {
281 		{0, 0, QIC_3095},			/* minor 0-3 */
282 		{0, 0, QIC_3095},			/* minor 4-7 */
283 		{0, 0, QIC_3095},			/* minor 8-11 */
284 		{0, 0, QIC_3095},			/* minor 12-15 */
285 	}}},
286 #if 0
287 	{{T_SEQUENTIAL, T_REMOV,
288 	 "EXABYTE ", "EXB-8200        ", ""},     {0, 12, {
289 		{0, 0, 0},				/* minor 0-3 */
290 		{0, 0, 0},				/* minor 4-7 */
291 		{0, 0, 0},				/* minor 8-11 */
292 		{0, 0, 0}				/* minor 12-15 */
293 	}}},
294 #endif
295 	{{T_SEQUENTIAL, T_REMOV,
296 	 "TEAC    ", "MT-2ST/N50      ", ""},     {ST_Q_IGNORE_LOADS, 0, {
297 		{0, 0, 0},			        /* minor 0-3 */
298 		{0, 0, 0},			        /* minor 4-7 */
299 		{0, 0, 0},			        /* minor 8-11 */
300 		{0, 0, 0}			        /* minor 12-15 */
301 	}}},
302 	{{T_SEQUENTIAL, T_REMOV,
303 	 "OnStream", "ADR50 Drive", ""},	  {ST_Q_UNIMODAL, 0, {
304 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 0-3 */
305 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 4-7 */
306 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 8-11 */
307 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 12-15 */
308 	}}},
309 	{{T_SEQUENTIAL, T_REMOV,
310 	 "OnStream DI-30",      "",   "1.0"},  {ST_Q_NOFILEMARKS, 0, {
311 		{0, 0, 0},                              /* minor 0-3 */
312 		{0, 0, 0},                              /* minor 4-7 */
313 		{0, 0, 0},                              /* minor 8-11 */
314 		{0, 0, 0}                               /* minor 12-15 */
315 	}}},
316 	{{T_SEQUENTIAL, T_REMOV,
317 	 "NCR H621", "0-STD-03-46F880 ", ""},     {ST_Q_NOPREVENT, 0, {
318 		{0, 0, 0},			       /* minor 0-3 */
319 		{0, 0, 0},			       /* minor 4-7 */
320 		{0, 0, 0},			       /* minor 8-11 */
321 		{0, 0, 0}			       /* minor 12-15 */
322 	}}},
323 	{{T_SEQUENTIAL, T_REMOV,
324 	 "Seagate STT3401A", "hp0atxa", ""},	{0, 0, {
325 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
326 		{ST_Q_FORCE_BLKSIZE, 1024, 0},		/* minor 4-7 */
327 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 8-11 */
328 		{ST_Q_FORCE_BLKSIZE, 512, 0}		/* minor 12-15 */
329 	}}},
330 };
331 
332 #define NOEJECT 0
333 #define EJECT 1
334 
335 static void	st_identify_drive(struct st_softc *,
336 		    struct scsipi_inquiry_pattern *);
337 static void	st_loadquirks(struct st_softc *);
338 static int	st_mount_tape(dev_t, int);
339 static void	st_unmount(struct st_softc *, boolean);
340 static int	st_decide_mode(struct st_softc *, boolean);
341 static void	ststart(struct scsipi_periph *);
342 static void	strestart(void *);
343 static void	stdone(struct scsipi_xfer *, int);
344 static int	st_read(struct st_softc *, char *, int, int);
345 static int	st_space(struct st_softc *, int, u_int, int);
346 static int	st_write_filemarks(struct st_softc *, int, int);
347 static int	st_check_eod(struct st_softc *, boolean, int *, int);
348 static int	st_load(struct st_softc *, u_int, int);
349 static int	st_rewind(struct st_softc *, u_int, int);
350 static int	st_interpret_sense(struct scsipi_xfer *);
351 static int	st_touch_tape(struct st_softc *);
352 static int	st_erase(struct st_softc *, int full, int flags);
353 static int	st_rdpos(struct st_softc *, int, uint32_t *);
354 static int	st_setpos(struct st_softc *, int, uint32_t *);
355 
356 static const struct scsipi_periphsw st_switch = {
357 	st_interpret_sense,
358 	ststart,
359 	NULL,
360 	stdone
361 };
362 
363 #if defined(ST_ENABLE_EARLYWARN)
364 #define	ST_INIT_FLAGS	ST_EARLYWARN
365 #else
366 #define	ST_INIT_FLAGS	0
367 #endif
368 
369 /*
370  * The routine called by the low level scsi routine when it discovers
371  * A device suitable for this driver
372  */
373 void
374 stattach(device_t parent, device_t self, void *aux)
375 {
376 	struct st_softc *st = device_private(self);
377 	struct scsipibus_attach_args *sa = aux;
378 	struct scsipi_periph *periph = sa->sa_periph;
379 
380 	SC_DEBUG(periph, SCSIPI_DB2, ("stattach: "));
381 	st->sc_dev = self;
382 
383 	/* Store information needed to contact our base driver */
384 	st->sc_periph = periph;
385 	periph->periph_dev = st->sc_dev;
386 	periph->periph_switch = &st_switch;
387 
388 	/* Set initial flags  */
389 	st->flags = ST_INIT_FLAGS;
390 
391 	/* Set up the buf queue for this device */
392 	bufq_alloc(&st->buf_queue, "fcfs", 0);
393 	callout_init(&st->sc_callout, 0);
394 
395 	/*
396 	 * Check if the drive is a known criminal and take
397 	 * Any steps needed to bring it into line
398 	 */
399 	st_identify_drive(st, &sa->sa_inqbuf);
400 	printf("\n");
401 	/* Use the subdriver to request information regarding the drive.  */
402 	printf("%s : %s", device_xname(st->sc_dev), st->quirkdata
403 	    ? "quirks apply, " : "");
404 	if (scsipi_test_unit_ready(periph,
405 	    XS_CTL_DISCOVERY | XS_CTL_SILENT | XS_CTL_IGNORE_MEDIA_CHANGE) ||
406 	    st->ops(st, ST_OPS_MODESENSE,
407 	    XS_CTL_DISCOVERY | XS_CTL_SILENT | XS_CTL_IGNORE_MEDIA_CHANGE))
408 		printf("drive empty\n");
409 	else {
410 		printf("density code %d, ", st->media_density);
411 		if (st->media_blksize > 0)
412 			printf("%d-byte", st->media_blksize);
413 		else
414 			printf("variable");
415 		printf(" blocks, write-%s\n",
416 		    (st->flags & ST_READONLY) ? "protected" : "enabled");
417 	}
418 
419 	st->stats = iostat_alloc(IOSTAT_TAPE, parent,
420 	    device_xname(st->sc_dev));
421 
422 	rnd_attach_source(&st->rnd_source, device_xname(st->sc_dev),
423 	    RND_TYPE_TAPE, 0);
424 }
425 
426 int
427 stdetach(device_t self, int flags)
428 {
429 	struct st_softc *st = device_private(self);
430 	int s, bmaj, cmaj, mn;
431 
432 	/* locate the major number */
433 	bmaj = bdevsw_lookup_major(&st_bdevsw);
434 	cmaj = cdevsw_lookup_major(&st_cdevsw);
435 
436 	/* kill any pending restart */
437 	callout_stop(&st->sc_callout);
438 
439 	s = splbio();
440 
441 	/* Kill off any queued buffers. */
442 	bufq_drain(st->buf_queue);
443 
444 	bufq_free(st->buf_queue);
445 
446 	/* Kill off any pending commands. */
447 	scsipi_kill_pending(st->sc_periph);
448 
449 	splx(s);
450 
451 	/* Nuke the vnodes for any open instances */
452 	mn = STUNIT(device_unit(self));
453 	vdevgone(bmaj, mn, mn+STNMINOR-1, VBLK);
454 	vdevgone(cmaj, mn, mn+STNMINOR-1, VCHR);
455 
456 	iostat_free(st->stats);
457 
458 	/* Unhook the entropy source. */
459 	rnd_detach_source(&st->rnd_source);
460 
461 	return 0;
462 }
463 
464 /*
465  * Use the inquiry routine in 'scsi_base' to get drive info so we can
466  * Further tailor our behaviour.
467  */
468 static void
469 st_identify_drive(struct st_softc *st, struct scsipi_inquiry_pattern *inqbuf)
470 {
471 	const struct st_quirk_inquiry_pattern *finger;
472 	int priority;
473 
474 	finger = scsipi_inqmatch(inqbuf,
475 	    st_quirk_patterns,
476 	    sizeof(st_quirk_patterns) / sizeof(st_quirk_patterns[0]),
477 	    sizeof(st_quirk_patterns[0]), &priority);
478 	if (priority != 0) {
479 		st->quirkdata = &finger->quirkdata;
480 		st->drive_quirks = finger->quirkdata.quirks;
481 		st->quirks = finger->quirkdata.quirks;	/* start value */
482 		st->page_0_size = finger->quirkdata.page_0_size;
483 		KASSERT(st->page_0_size <= MAX_PAGE_0_SIZE);
484 		st_loadquirks(st);
485 	}
486 }
487 
488 /*
489  * initialise the subdevices to the default (QUIRK) state.
490  * this will remove any setting made by the system operator or previous
491  * operations.
492  */
493 static void
494 st_loadquirks(struct st_softc *st)
495 {
496 	const struct	modes *mode;
497 	struct	modes *mode2;
498 	int i;
499 
500 	mode = st->quirkdata->modes;
501 	mode2 = st->modes;
502 	for (i = 0; i < 4; i++) {
503 		memset(mode2, 0, sizeof(struct modes));
504 		st->modeflags[i] &= ~(BLKSIZE_SET_BY_QUIRK |
505 		    DENSITY_SET_BY_QUIRK | BLKSIZE_SET_BY_USER |
506 		    DENSITY_SET_BY_USER);
507 		if ((mode->quirks | st->drive_quirks) & ST_Q_FORCE_BLKSIZE) {
508 			mode2->blksize = mode->blksize;
509 			st->modeflags[i] |= BLKSIZE_SET_BY_QUIRK;
510 		}
511 		if (mode->density) {
512 			mode2->density = mode->density;
513 			st->modeflags[i] |= DENSITY_SET_BY_QUIRK;
514 		}
515 		mode2->quirks |= mode->quirks;
516 		mode++;
517 		mode2++;
518 	}
519 }
520 
521 /* open the device. */
522 static int
523 stopen(dev_t dev, int flags, int mode, struct lwp *l)
524 {
525 	u_int stmode, dsty;
526 	int error, sflags, unit, tries, ntries;
527 	struct st_softc *st;
528 	struct scsipi_periph *periph;
529 	struct scsipi_adapter *adapt;
530 
531 	unit = STUNIT(dev);
532 	st = device_lookup_private(&st_cd, unit);
533 	if (st == NULL)
534 		return ENXIO;
535 
536 	stmode = STMODE(dev);
537 	dsty = STDSTY(dev);
538 
539 	periph = st->sc_periph;
540 	adapt = periph->periph_channel->chan_adapter;
541 
542 	SC_DEBUG(periph, SCSIPI_DB1,
543 	    ("open: dev=0x%"PRIx64" (unit %d (of %d))\n", dev, unit,
544 	    st_cd.cd_ndevs));
545 
546 	/* Only allow one at a time */
547 	if (periph->periph_flags & PERIPH_OPEN) {
548 		aprint_error_dev(st->sc_dev, "already open\n");
549 		return EBUSY;
550 	}
551 
552 	if ((error = scsipi_adapter_addref(adapt)) != 0)
553 		return error;
554 
555 	/* clear any latched errors. */
556 	st->mt_resid = 0;
557 	st->mt_erreg = 0;
558 	st->asc = 0;
559 	st->ascq = 0;
560 
561 	/*
562 	 * Catch any unit attention errors. Be silent about this
563 	 * unless we're already mounted. We ignore media change
564 	 * if we're in control mode or not mounted yet.
565 	 */
566 	if ((st->flags & ST_MOUNTED) == 0 || stmode == CTRL_MODE) {
567 #ifdef SCSIDEBUG
568 		sflags = XS_CTL_IGNORE_MEDIA_CHANGE;
569 #else
570 		sflags = XS_CTL_SILENT|XS_CTL_IGNORE_MEDIA_CHANGE;
571 #endif
572 	} else
573 		sflags = 0;
574 
575 	/*
576 	 * If we're already mounted or we aren't configured for
577 	 * a mount delay, only try a test unit ready once. Otherwise,
578 	 * try up to ST_MOUNT_DELAY times with a rest interval of
579 	 * one second between each try.
580 	 */
581 	if ((st->flags & ST_MOUNTED) || ST_MOUNT_DELAY == 0)
582 		ntries = 1;
583 	else
584 		ntries = ST_MOUNT_DELAY;
585 
586 	for (error = tries = 0; tries < ntries; tries++) {
587 		int slpintr, oflags;
588 
589 		/*
590 		 * If we had no error, or we're opening the control mode
591 		 * device, we jump out right away.
592 		 */
593 		error = scsipi_test_unit_ready(periph, sflags);
594 		if (error == 0 || stmode == CTRL_MODE)
595 			break;
596 
597 		/*
598 		 * We had an error.
599 		 *
600 		 * If we're already mounted or we aren't configured for
601 		 * a mount delay, or the error isn't a NOT READY error,
602 		 * skip to the error exit now.
603 		 */
604 		if ((st->flags & ST_MOUNTED) || ST_MOUNT_DELAY == 0 ||
605 		    (st->mt_key != SKEY_NOT_READY)) {
606 			goto bad;
607 		}
608 
609 		/* clear any latched errors. */
610 		st->mt_resid = 0;
611 		st->mt_erreg = 0;
612 		st->asc = 0;
613 		st->ascq = 0;
614 
615 		/*
616 		 * Fake that we have the device open so
617 		 * we block other apps from getting in.
618 		 */
619 		oflags = periph->periph_flags;
620 		periph->periph_flags |= PERIPH_OPEN;
621 
622 		slpintr = kpause("stload", true, hz, NULL);
623 
624 		periph->periph_flags = oflags;	/* restore flags */
625 		if (slpintr != 0 && slpintr != EWOULDBLOCK) {
626 			goto bad;
627 		}
628 	}
629 
630 
631 	/*
632 	 * If the mode is 3 (e.g. minor = 3,7,11,15) then the device has
633 	 * been opened to set defaults and perform other, usually non-I/O
634 	 * related, operations. In this case, do a quick check to see
635 	 * whether the unit actually had a tape loaded (this will be known
636 	 * as to whether or not we got a NOT READY for the above
637 	 * unit attention). If a tape is there, go do a mount sequence.
638 	 */
639 	if (stmode == CTRL_MODE && st->mt_key == SKEY_NOT_READY) {
640 		periph->periph_flags |= PERIPH_OPEN;
641 		return 0;
642 	}
643 
644 	/*
645 	 * If we get this far and had an error set, that means we failed
646 	 * to pass the 'test unit ready' test for the non-controlmode device,
647 	 * so we bounce the open.
648 	 */
649 	if (error)
650 		return error;
651 
652 	/* Else, we're now committed to saying we're open. */
653 	periph->periph_flags |= PERIPH_OPEN; /* unit attn are now errors */
654 
655 	/*
656 	 * If it's a different mode, or if the media has been
657 	 * invalidated, unmount the tape from the previous
658 	 * session but continue with open processing
659 	 */
660 	if (st->last_dsty != dsty ||
661 	    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
662 		st_unmount(st, NOEJECT);
663 
664 	/*
665 	 * If we are not mounted, then we should start a new
666 	 * mount session.
667 	 */
668 	if (!(st->flags & ST_MOUNTED)) {
669 		if ((error = st_mount_tape(dev, flags)) != 0)
670 			goto bad;
671 		st->last_dsty = dsty;
672 	}
673 	if (!(st->quirks & ST_Q_NOPREVENT)) {
674 		scsipi_prevent(periph, SPAMR_PREVENT_DT,
675 		    XS_CTL_IGNORE_ILLEGAL_REQUEST | XS_CTL_IGNORE_NOT_READY);
676 	}
677 
678 	SC_DEBUG(periph, SCSIPI_DB2, ("open complete\n"));
679 	return 0;
680 
681 bad:
682 	st_unmount(st, NOEJECT);
683 	scsipi_adapter_delref(adapt);
684 	periph->periph_flags &= ~PERIPH_OPEN;
685 	return error;
686 }
687 
688 static int
689 stclose(dev_t dev, int flags, int mode, struct lwp *l)
690 {
691 	int stxx, error = 0;
692 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
693 	struct scsipi_periph *periph = st->sc_periph;
694 	struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;
695 
696 	SC_DEBUG(st->sc_periph, SCSIPI_DB1, ("closing\n"));
697 
698 	/*
699 	 * Make sure that a tape opened in write-only mode will have
700 	 * file marks written on it when closed, even if not written to.
701 	 *
702 	 * This is for SUN compatibility. Actually, the Sun way of
703 	 * things is to:
704 	 *
705 	 *	only write filemarks if there are fmks to be written and
706 	 *   		- open for write (possibly read/write)
707 	 *		- the last operation was a write
708 	 * 	or:
709 	 *		- opened for wronly
710 	 *		- no data was written (including filemarks)
711 	 */
712 
713 	stxx = st->flags & (ST_WRITTEN | ST_FM_WRITTEN);
714 	if (((flags & FWRITE) && stxx == ST_WRITTEN) ||
715 	    ((flags & O_ACCMODE) == FWRITE && stxx == 0)) {
716 		int nm;
717 		error = st_check_eod(st, FALSE, &nm, 0);
718 	}
719 
720 	/* Allow robots to eject tape if needed.  */
721 	scsipi_prevent(periph, SPAMR_ALLOW,
722 	    XS_CTL_IGNORE_ILLEGAL_REQUEST | XS_CTL_IGNORE_NOT_READY);
723 
724 	switch (STMODE(dev)) {
725 	case NORMAL_MODE:
726 		st_unmount(st, NOEJECT);
727 		break;
728 	case NOREW_MODE:
729 	case CTRL_MODE:
730 		/*
731 		 * Leave mounted unless media seems to have been removed.
732 		 *
733 		 * Otherwise, if we're to terminate a tape with more than one
734 		 * filemark [ and because we're not rewinding here ], backspace
735 		 * one filemark so that later appends will see an unbroken
736 		 * sequence of:
737 		 *
738 		 *	file - FMK - file - FMK ... file - FMK FMK (EOM)
739 		 */
740 		if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0) {
741 			st_unmount(st, NOEJECT);
742 		} else if (error == 0) {
743 			/*
744 			 * ST_WRITTEN was preserved from above.
745 			 *
746 			 * All we need to know here is:
747 			 *
748 			 *	Were we writing this tape and was the last
749 			 *	operation a write?
750 			 *
751 			 *	Are there supposed to be 2FM at EOD?
752 			 *
753 			 * If both statements are true, then we backspace
754 			 * one filemark.
755 			 */
756 			stxx |= (st->flags & ST_2FM_AT_EOD);
757 			if ((flags & FWRITE) != 0 &&
758 			    (stxx == (ST_2FM_AT_EOD|ST_WRITTEN))) {
759 				error = st_space(st, -1, SP_FILEMARKS, 0);
760 			}
761 		}
762 		break;
763 	case EJECT_MODE:
764 		st_unmount(st, EJECT);
765 		break;
766 	}
767 
768 	scsipi_wait_drain(periph);
769 
770 	scsipi_adapter_delref(adapt);
771 	periph->periph_flags &= ~PERIPH_OPEN;
772 
773 	return error;
774 }
775 
776 /*
777  * Start a new mount session.
778  * Copy in all the default parameters from the selected device mode.
779  * and try guess any that seem to be defaulted.
780  */
781 static int
782 st_mount_tape(dev_t dev, int flags)
783 {
784 	int unit;
785 	u_int dsty;
786 	struct st_softc *st;
787 	struct scsipi_periph *periph;
788 	int error = 0;
789 
790 	unit = STUNIT(dev);
791 	dsty = STDSTY(dev);
792 	st = device_lookup_private(&st_cd, unit);
793 	periph = st->sc_periph;
794 
795 	if (st->flags & ST_MOUNTED)
796 		return 0;
797 
798 	SC_DEBUG(periph, SCSIPI_DB1, ("mounting\n "));
799 	st->flags |= ST_NEW_MOUNT;
800 	st->quirks = st->drive_quirks | st->modes[dsty].quirks;
801 	/*
802 	 * If the media is new, then make sure we give it a chance to
803 	 * to do a 'load' instruction.  (We assume it is new.)
804 	 */
805 	if ((error = st_load(st, LD_LOAD, XS_CTL_SILENT)) != 0)
806 		return error;
807 	/*
808 	 * Throw another dummy instruction to catch
809 	 * 'Unit attention' errors. Many drives give
810 	 * these after doing a Load instruction (with
811 	 * the MEDIUM MAY HAVE CHANGED asc/ascq).
812 	 */
813 	scsipi_test_unit_ready(periph, XS_CTL_SILENT);	/* XXX */
814 
815 	/*
816 	 * Some devices can't tell you much until they have been
817 	 * asked to look at the media. This quirk does this.
818 	 */
819 	if (st->quirks & ST_Q_SENSE_HELP)
820 		if ((error = st_touch_tape(st)) != 0)
821 			return error;
822 	/*
823 	 * Load the physical device parameters
824 	 * loads: blkmin, blkmax
825 	 */
826 	if ((error = st->ops(st, ST_OPS_RBL, 0)) != 0)
827 		return error;
828 	/*
829 	 * Load the media dependent parameters
830 	 * includes: media_blksize,media_density,numblks
831 	 * As we have a tape in, it should be reflected here.
832 	 * If not you may need the "quirk" above.
833 	 */
834 	if ((error = st->ops(st, ST_OPS_MODESENSE, 0)) != 0)
835 		return error;
836 	/*
837 	 * If we have gained a permanent density from somewhere,
838 	 * then use it in preference to the one supplied by
839 	 * default by the driver.
840 	 */
841 	if (st->modeflags[dsty] & (DENSITY_SET_BY_QUIRK | DENSITY_SET_BY_USER))
842 		st->density = st->modes[dsty].density;
843 	else
844 		st->density = st->media_density;
845 	/*
846 	 * If we have gained a permanent blocksize
847 	 * then use it in preference to the one supplied by
848 	 * default by the driver.
849 	 */
850 	st->flags &= ~ST_FIXEDBLOCKS;
851 	if (st->modeflags[dsty] &
852 	    (BLKSIZE_SET_BY_QUIRK | BLKSIZE_SET_BY_USER)) {
853 		st->blksize = st->modes[dsty].blksize;
854 		if (st->blksize)
855 			st->flags |= ST_FIXEDBLOCKS;
856 	} else {
857 		if ((error = st_decide_mode(st, FALSE)) != 0)
858 			return error;
859 	}
860 	if ((error = st->ops(st, ST_OPS_MODESELECT, 0)) != 0) {
861 		/* ATAPI will return ENODEV for this, and this may be OK */
862 		if (error != ENODEV) {
863 			aprint_error_dev(st->sc_dev,
864 			    "cannot set selected mode\n");
865 			return error;
866 		}
867 	}
868 	st->flags &= ~ST_NEW_MOUNT;
869 	st->flags |= ST_MOUNTED;
870 	periph->periph_flags |= PERIPH_MEDIA_LOADED;	/* move earlier? */
871 	st->blkno = st->fileno = (daddr_t) 0;
872 	return 0;
873 }
874 
875 /*
876  * End the present mount session.
877  * Rewind, and optionally eject the tape.
878  * Reset various flags to indicate that all new
879  * operations require another mount operation
880  */
881 static void
882 st_unmount(struct st_softc *st, boolean eject)
883 {
884 	struct scsipi_periph *periph = st->sc_periph;
885 	int nmarks;
886 
887 	if ((st->flags & ST_MOUNTED) == 0)
888 		return;
889 	SC_DEBUG(periph, SCSIPI_DB1, ("unmounting\n"));
890 	st_check_eod(st, FALSE, &nmarks, XS_CTL_IGNORE_NOT_READY);
891 	st_rewind(st, 0, XS_CTL_IGNORE_NOT_READY);
892 
893 	/*
894 	 * Section 9.3.3 of the SCSI specs states that a device shall return
895 	 * the density value specified in the last succesfull MODE SELECT
896 	 * after an unload operation, in case it is not able to
897 	 * automatically determine the density of the new medium.
898 	 *
899 	 * So we instruct the device to use the default density, which will
900 	 * prevent the use of stale density values (in particular,
901 	 * in st_touch_tape().
902 	 */
903 	st->density = 0;
904 	if (st->ops(st, ST_OPS_MODESELECT, 0) != 0) {
905 		aprint_error_dev(st->sc_dev,
906 		    "WARNING: cannot revert to default density\n");
907 	}
908 
909 	if (eject) {
910 		if (!(st->quirks & ST_Q_NOPREVENT)) {
911 			scsipi_prevent(periph, SPAMR_ALLOW,
912 			    XS_CTL_IGNORE_ILLEGAL_REQUEST |
913 			    XS_CTL_IGNORE_NOT_READY);
914 		}
915 		st_load(st, LD_UNLOAD, XS_CTL_IGNORE_NOT_READY);
916 		st->blkno = st->fileno = (daddr_t) -1;
917 	} else {
918 		st->blkno = st->fileno = (daddr_t) 0;
919 	}
920 	st->flags &= ~(ST_MOUNTED | ST_NEW_MOUNT);
921 	periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
922 }
923 
924 /*
925  * Given all we know about the device, media, mode, 'quirks' and
926  * initial operation, make a decision as to how we should be set
927  * to run (regarding blocking and EOD marks)
928  */
929 int
930 st_decide_mode(struct st_softc *st, boolean first_read)
931 {
932 
933 	SC_DEBUG(st->sc_periph, SCSIPI_DB2, ("starting block mode decision\n"));
934 
935 	/*
936 	 * If the drive can only handle fixed-length blocks and only at
937 	 * one size, perhaps we should just do that.
938 	 */
939 	if (st->blkmin && (st->blkmin == st->blkmax)) {
940 		st->flags |= ST_FIXEDBLOCKS;
941 		st->blksize = st->blkmin;
942 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
943 		    ("blkmin == blkmax of %d\n", st->blkmin));
944 		goto done;
945 	}
946 	/*
947 	 * If the tape density mandates (or even suggests) use of fixed
948 	 * or variable-length blocks, comply.
949 	 */
950 	switch (st->density) {
951 	case HALFINCH_800:
952 	case HALFINCH_1600:
953 	case HALFINCH_6250:
954 	case DDS:
955 		st->flags &= ~ST_FIXEDBLOCKS;
956 		st->blksize = 0;
957 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
958 		    ("density specified variable\n"));
959 		goto done;
960 	case QIC_11:
961 	case QIC_24:
962 	case QIC_120:
963 	case QIC_150:
964 	case QIC_525:
965 	case QIC_1320:
966 	case QIC_3095:
967 	case QIC_3220:
968 		st->flags |= ST_FIXEDBLOCKS;
969 		if (st->media_blksize > 0)
970 			st->blksize = st->media_blksize;
971 		else
972 			st->blksize = DEF_FIXED_BSIZE;
973 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
974 		    ("density specified fixed\n"));
975 		goto done;
976 	}
977 	/*
978 	 * If we're about to read the tape, perhaps we should choose
979 	 * fixed or variable-length blocks and block size according to
980 	 * what the drive found on the tape.
981 	 */
982 	if (first_read &&
983 	    (!(st->quirks & ST_Q_BLKSIZE) || (st->media_blksize == 0) ||
984 	    (st->media_blksize == DEF_FIXED_BSIZE) ||
985 	    (st->media_blksize == 1024))) {
986 		if (st->media_blksize > 0)
987 			st->flags |= ST_FIXEDBLOCKS;
988 		else
989 			st->flags &= ~ST_FIXEDBLOCKS;
990 		st->blksize = st->media_blksize;
991 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
992 		    ("Used media_blksize of %d\n", st->media_blksize));
993 		goto done;
994 	}
995 	/*
996 	 * We're getting no hints from any direction.  Choose variable-
997 	 * length blocks arbitrarily.
998 	 */
999 	st->flags &= ~ST_FIXEDBLOCKS;
1000 	st->blksize = 0;
1001 	SC_DEBUG(st->sc_periph, SCSIPI_DB3,
1002 	    ("Give up and default to variable mode\n"));
1003 
1004 done:
1005 	/*
1006 	 * Decide whether or not to write two file marks to signify end-
1007 	 * of-data.  Make the decision as a function of density.  If
1008 	 * the decision is not to use a second file mark, the SCSI BLANK
1009 	 * CHECK condition code will be recognized as end-of-data when
1010 	 * first read.
1011 	 * (I think this should be a by-product of fixed/variable..julian)
1012 	 */
1013 	switch (st->density) {
1014 /*      case 8 mm:   What is the SCSI density code for 8 mm, anyway? */
1015 	case QIC_11:
1016 	case QIC_24:
1017 	case QIC_120:
1018 	case QIC_150:
1019 	case QIC_525:
1020 	case QIC_1320:
1021 	case QIC_3095:
1022 	case QIC_3220:
1023 		st->flags &= ~ST_2FM_AT_EOD;
1024 		break;
1025 	default:
1026 		st->flags |= ST_2FM_AT_EOD;
1027 	}
1028 	return 0;
1029 }
1030 
1031 /*
1032  * Actually translate the requested transfer into
1033  * one the physical driver can understand
1034  * The transfer is described by a buf and will include
1035  * only one physical transfer.
1036  */
1037 static void
1038 ststrategy(struct buf *bp)
1039 {
1040 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(bp->b_dev));
1041 	int s;
1042 
1043 	SC_DEBUG(st->sc_periph, SCSIPI_DB1,
1044 	    ("ststrategy %d bytes @ blk %" PRId64 "\n", bp->b_bcount,
1045 	        bp->b_blkno));
1046 	/* If it's a null transfer, return immediately */
1047 	if (bp->b_bcount == 0)
1048 		goto abort;
1049 
1050 	/* If offset is negative, error */
1051 	if (bp->b_blkno < 0) {
1052 		bp->b_error = EINVAL;
1053 		goto abort;
1054 	}
1055 
1056 	/* Odd sized request on fixed drives are verboten */
1057 	if (st->flags & ST_FIXEDBLOCKS) {
1058 		if (bp->b_bcount % st->blksize) {
1059 			aprint_error_dev(st->sc_dev, "bad request, must be multiple of %d\n",
1060 			    st->blksize);
1061 			bp->b_error = EIO;
1062 			goto abort;
1063 		}
1064 	}
1065 	/* as are out-of-range requests on variable drives. */
1066 	else if (bp->b_bcount < st->blkmin ||
1067 	    (st->blkmax && bp->b_bcount > st->blkmax)) {
1068 		aprint_error_dev(st->sc_dev, "bad request, must be between %d and %d\n",
1069 		    st->blkmin, st->blkmax);
1070 		bp->b_error = EIO;
1071 		goto abort;
1072 	}
1073 	s = splbio();
1074 
1075 	/*
1076 	 * Place it in the queue of activities for this tape
1077 	 * at the end (a bit silly because we only have on user..
1078 	 * (but it could fork()))
1079 	 */
1080 	bufq_put(st->buf_queue, bp);
1081 
1082 	/*
1083 	 * Tell the device to get going on the transfer if it's
1084 	 * not doing anything, otherwise just wait for completion
1085 	 * (All a bit silly if we're only allowing 1 open but..)
1086 	 */
1087 	ststart(st->sc_periph);
1088 
1089 	splx(s);
1090 	return;
1091 abort:
1092 	/*
1093 	 * Reset the residue because we didn't do anything,
1094 	 * and send the buffer back as done.
1095 	 */
1096 	bp->b_resid = bp->b_bcount;
1097 	biodone(bp);
1098 	return;
1099 }
1100 
1101 /*
1102  * ststart looks to see if there is a buf waiting for the device
1103  * and that the device is not already busy. If both are true,
1104  * It dequeues the buf and creates a scsi command to perform the
1105  * transfer required. The transfer request will call scsipi_done
1106  * on completion, which will in turn call this routine again
1107  * so that the next queued transfer is performed.
1108  * The bufs are queued by the strategy routine (ststrategy)
1109  *
1110  * This routine is also called after other non-queued requests
1111  * have been made of the scsi driver, to ensure that the queue
1112  * continues to be drained.
1113  * ststart() is called at splbio
1114  */
1115 static void
1116 ststart(struct scsipi_periph *periph)
1117 {
1118 	struct st_softc *st = device_private(periph->periph_dev);
1119 	struct buf *bp;
1120 	struct scsi_rw_tape cmd;
1121 	struct scsipi_xfer *xs;
1122 	int flags, error __diagused;
1123 
1124 	SC_DEBUG(periph, SCSIPI_DB2, ("ststart "));
1125 	/* See if there is a buf to do and we are not already  doing one */
1126 	while (periph->periph_active < periph->periph_openings) {
1127 		/* if a special awaits, let it proceed first */
1128 		if (periph->periph_flags & PERIPH_WAITING) {
1129 			periph->periph_flags &= ~PERIPH_WAITING;
1130 			wakeup((void *)periph);
1131 			return;
1132 		}
1133 
1134 		/*
1135 		 * If the device has been unmounted by the user
1136 		 * then throw away all requests until done.
1137 		 */
1138 		if (__predict_false((st->flags & ST_MOUNTED) == 0 ||
1139 		    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)) {
1140 			if ((bp = bufq_get(st->buf_queue)) != NULL) {
1141 				/* make sure that one implies the other.. */
1142 				periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
1143 				bp->b_error = EIO;
1144 				bp->b_resid = bp->b_bcount;
1145 				biodone(bp);
1146 				continue;
1147 			} else
1148 				return;
1149 		}
1150 
1151 		if ((bp = bufq_peek(st->buf_queue)) == NULL)
1152 			return;
1153 
1154 		iostat_busy(st->stats);
1155 
1156 		/*
1157 		 * only FIXEDBLOCK devices have pending I/O or space operations.
1158 		 */
1159 		if (st->flags & ST_FIXEDBLOCKS) {
1160 			/*
1161 			 * If we are at a filemark but have not reported it yet
1162 			 * then we should report it now
1163 			 */
1164 			if (st->flags & ST_AT_FILEMARK) {
1165 				if ((bp->b_flags & B_READ) == B_WRITE) {
1166 					/*
1167 					 * Handling of ST_AT_FILEMARK in
1168 					 * st_space will fill in the right file
1169 					 * mark count.
1170 					 * Back up over filemark
1171 					 */
1172 					if (st_space(st, 0, SP_FILEMARKS, 0)) {
1173 						bufq_get(st->buf_queue);
1174 						bp->b_error = EIO;
1175 						bp->b_resid = bp->b_bcount;
1176 						biodone(bp);
1177 						continue;
1178 					}
1179 				} else {
1180 					bufq_get(st->buf_queue);
1181 					bp->b_resid = bp->b_bcount;
1182 					bp->b_error = 0;
1183 					st->flags &= ~ST_AT_FILEMARK;
1184 					biodone(bp);
1185 					continue;	/* seek more work */
1186 				}
1187 			}
1188 		}
1189 		/*
1190 		 * If we are at EOM but have not reported it
1191 		 * yet then we should report it now.
1192 		 */
1193 		if (st->flags & (ST_EOM_PENDING|ST_EIO_PENDING)) {
1194 			bufq_get(st->buf_queue);
1195 			bp->b_resid = bp->b_bcount;
1196 			if (st->flags & ST_EIO_PENDING)
1197 				bp->b_error = EIO;
1198 			st->flags &= ~(ST_EOM_PENDING|ST_EIO_PENDING);
1199 			biodone(bp);
1200 			continue;	/* seek more work */
1201 		}
1202 
1203 		/* Fill out the scsi command */
1204 		memset(&cmd, 0, sizeof(cmd));
1205 		flags = XS_CTL_NOSLEEP | XS_CTL_ASYNC;
1206 		if ((bp->b_flags & B_READ) == B_WRITE) {
1207 			cmd.opcode = WRITE;
1208 			st->flags &= ~ST_FM_WRITTEN;
1209 			flags |= XS_CTL_DATA_OUT;
1210 		} else {
1211 			cmd.opcode = READ;
1212 			flags |= XS_CTL_DATA_IN;
1213 		}
1214 
1215 		/*
1216 		 * Handle "fixed-block-mode" tape drives by using the
1217 		 * block count instead of the length.
1218 		 */
1219 		if (st->flags & ST_FIXEDBLOCKS) {
1220 			cmd.byte2 |= SRW_FIXED;
1221 			_lto3b(bp->b_bcount / st->blksize, cmd.len);
1222 		} else
1223 			_lto3b(bp->b_bcount, cmd.len);
1224 
1225 		/* Clear 'position updated' indicator */
1226 		st->flags &= ~ST_POSUPDATED;
1227 
1228 		/* go ask the adapter to do all this for us */
1229 		xs = scsipi_make_xs(periph,
1230 		    (struct scsipi_generic *)&cmd, sizeof(cmd),
1231 		    (u_char *)bp->b_data, bp->b_bcount,
1232 		    0, ST_IO_TIME, bp, flags);
1233 		if (__predict_false(xs == NULL)) {
1234 			/*
1235 			 * out of memory. Keep this buffer in the queue, and
1236 			 * retry later.
1237 			 */
1238 			callout_reset(&st->sc_callout, hz / 2, strestart,
1239 			    periph);
1240 			return;
1241 		}
1242 		/*
1243 		 * need to dequeue the buffer before queuing the command,
1244 		 * because cdstart may be called recursively from the
1245 		 * HBA driver
1246 		 */
1247 #ifdef DIAGNOSTIC
1248 		if (bufq_get(st->buf_queue) != bp)
1249 			panic("ststart(): dequeued wrong buf");
1250 #else
1251 		bufq_get(st->buf_queue);
1252 #endif
1253 		error = scsipi_execute_xs(xs);
1254 		/* with a scsipi_xfer preallocated, scsipi_command can't fail */
1255 		KASSERT(error == 0);
1256 	} /* go back and see if we can cram more work in.. */
1257 }
1258 
1259 static void
1260 strestart(void *v)
1261 {
1262 	int s = splbio();
1263 	ststart((struct scsipi_periph *)v);
1264 	splx(s);
1265 }
1266 
1267 static void
1268 stdone(struct scsipi_xfer *xs, int error)
1269 {
1270 	struct st_softc *st = device_private(xs->xs_periph->periph_dev);
1271 	struct buf *bp = xs->bp;
1272 
1273 	if (bp) {
1274 		bp->b_error = error;
1275 		bp->b_resid = xs->resid;
1276 		/*
1277 		 * buggy device ? A SDLT320 can report an info
1278 		 * field of 0x3de8000 on a Media Error/Write Error
1279 		 * for this CBD: 0x0a 00 00 80 00 00
1280 		 */
1281 		if (bp->b_resid > bp->b_bcount || bp->b_resid < 0)
1282 			bp->b_resid = bp->b_bcount;
1283 
1284 		if ((bp->b_flags & B_READ) == B_WRITE)
1285 			st->flags |= ST_WRITTEN;
1286 		else
1287 			st->flags &= ~ST_WRITTEN;
1288 
1289 		iostat_unbusy(st->stats, bp->b_bcount,
1290 			     ((bp->b_flags & B_READ) == B_READ));
1291 
1292 		rnd_add_uint32(&st->rnd_source, bp->b_blkno);
1293 
1294 		if ((st->flags & ST_POSUPDATED) == 0) {
1295 			if (error) {
1296 				st->fileno = st->blkno = -1;
1297 			} else if (st->blkno != -1) {
1298 				if (st->flags & ST_FIXEDBLOCKS)
1299 					st->blkno +=
1300 					    (bp->b_bcount / st->blksize);
1301 				else
1302 					st->blkno++;
1303 			}
1304 		}
1305 		biodone(bp);
1306 	}
1307 }
1308 
1309 static int
1310 stread(dev_t dev, struct uio *uio, int iomode)
1311 {
1312 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
1313 
1314 	return physio(ststrategy, NULL, dev, B_READ,
1315 	    st->sc_periph->periph_channel->chan_adapter->adapt_minphys, uio);
1316 }
1317 
1318 static int
1319 stwrite(dev_t dev, struct uio *uio, int iomode)
1320 {
1321 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
1322 
1323 	return physio(ststrategy, NULL, dev, B_WRITE,
1324 	    st->sc_periph->periph_channel->chan_adapter->adapt_minphys, uio);
1325 }
1326 
1327 /*
1328  * Perform special action on behalf of the user;
1329  * knows about the internals of this device
1330  */
1331 static int
1332 stioctl(dev_t dev, u_long cmd, void *arg, int flag, struct lwp *l)
1333 {
1334 	int error = 0;
1335 	int unit;
1336 	int number, nmarks, dsty;
1337 	int flags;
1338 	struct st_softc *st;
1339 	int hold_blksize;
1340 	uint8_t hold_density;
1341 	struct mtop *mt = (struct mtop *) arg;
1342 
1343 	/* Find the device that the user is talking about */
1344 	flags = 0;		/* give error messages, act on errors etc. */
1345 	unit = STUNIT(dev);
1346 	dsty = STDSTY(dev);
1347 	st = device_lookup_private(&st_cd, unit);
1348 	hold_blksize = st->blksize;
1349 	hold_density = st->density;
1350 
1351 	switch ((u_int)cmd) {
1352 	case MTIOCGET: {
1353 		struct mtget *g = (struct mtget *) arg;
1354 		/*
1355 		 * (to get the current state of READONLY)
1356 		 */
1357 		error = st->ops(st, ST_OPS_MODESENSE, XS_CTL_SILENT);
1358 		if (error) {
1359 			/*
1360 			 * Ignore the error if in control mode;
1361 			 * this is mandated by st(4).
1362 			 */
1363 			if (STMODE(dev) != CTRL_MODE)
1364 				break;
1365 			error = 0;
1366 		}
1367 		SC_DEBUG(st->sc_periph, SCSIPI_DB1, ("[ioctl: get status]\n"));
1368 		memset(g, 0, sizeof(struct mtget));
1369 		g->mt_type = MT_ISAR;	/* Ultrix compat *//*? */
1370 		g->mt_blksiz = st->blksize;
1371 		g->mt_density = st->density;
1372 		g->mt_mblksiz[0] = st->modes[0].blksize;
1373 		g->mt_mblksiz[1] = st->modes[1].blksize;
1374 		g->mt_mblksiz[2] = st->modes[2].blksize;
1375 		g->mt_mblksiz[3] = st->modes[3].blksize;
1376 		g->mt_mdensity[0] = st->modes[0].density;
1377 		g->mt_mdensity[1] = st->modes[1].density;
1378 		g->mt_mdensity[2] = st->modes[2].density;
1379 		g->mt_mdensity[3] = st->modes[3].density;
1380 		g->mt_fileno = st->fileno;
1381 		g->mt_blkno = st->blkno;
1382 		if (st->flags & ST_READONLY)
1383 			g->mt_dsreg |= MT_DS_RDONLY;
1384 		if (st->flags & ST_MOUNTED)
1385 			g->mt_dsreg |= MT_DS_MOUNTED;
1386 		g->mt_resid = st->mt_resid;
1387 		g->mt_erreg = st->mt_erreg;
1388 		/*
1389 		 * clear latched errors.
1390 		 */
1391 		st->mt_resid = 0;
1392 		st->mt_erreg = 0;
1393 		st->asc = 0;
1394 		st->ascq = 0;
1395 		break;
1396 	}
1397 	case MTIOCTOP: {
1398 		SC_DEBUG(st->sc_periph, SCSIPI_DB1,
1399 		    ("[ioctl: op=0x%x count=0x%x]\n", mt->mt_op,
1400 			mt->mt_count));
1401 
1402 		/* compat: in U*x it is a short */
1403 		number = mt->mt_count;
1404 		switch ((short) (mt->mt_op)) {
1405 		case MTWEOF:	/* write an end-of-file record */
1406 			error = st_write_filemarks(st, number, flags);
1407 			break;
1408 		case MTBSF:	/* backward space file */
1409 			number = -number;
1410 		case MTFSF:	/* forward space file */
1411 			error = st_check_eod(st, FALSE, &nmarks, flags);
1412 			if (!error)
1413 				error = st_space(st, number - nmarks,
1414 				    SP_FILEMARKS, flags);
1415 			break;
1416 		case MTBSR:	/* backward space record */
1417 			number = -number;
1418 		case MTFSR:	/* forward space record */
1419 			error = st_check_eod(st, true, &nmarks, flags);
1420 			if (!error)
1421 				error = st_space(st, number, SP_BLKS, flags);
1422 			break;
1423 		case MTREW:	/* rewind */
1424 			error = st_rewind(st, 0, flags);
1425 			break;
1426 		case MTOFFL:	/* rewind and put the drive offline */
1427 			st_unmount(st, EJECT);
1428 			break;
1429 		case MTNOP:	/* no operation, sets status only */
1430 			break;
1431 		case MTRETEN:	/* retension the tape */
1432 			error = st_load(st, LD_RETENSION, flags);
1433 			if (!error)
1434 				error = st_load(st, LD_LOAD, flags);
1435 			break;
1436 		case MTEOM:	/* forward space to end of media */
1437 			error = st_check_eod(st, FALSE, &nmarks, flags);
1438 			if (!error)
1439 				error = st_space(st, 1, SP_EOM, flags);
1440 			break;
1441 		case MTCACHE:	/* enable controller cache */
1442 			st->flags &= ~ST_DONTBUFFER;
1443 			goto try_new_value;
1444 		case MTNOCACHE:	/* disable controller cache */
1445 			st->flags |= ST_DONTBUFFER;
1446 			goto try_new_value;
1447 		case MTERASE:	/* erase volume */
1448 			error = st_erase(st, number, flags);
1449 			break;
1450 		case MTSETBSIZ:	/* Set block size for device */
1451 #ifdef	NOTYET
1452 			if (!(st->flags & ST_NEW_MOUNT)) {
1453 				uprintf("re-mount tape before changing "
1454 				    "blocksize");
1455 				error = EINVAL;
1456 				break;
1457 			}
1458 #endif
1459 			if (number == 0)
1460 				st->flags &= ~ST_FIXEDBLOCKS;
1461 			else {
1462 				if ((st->blkmin || st->blkmax) &&
1463 				    (number < st->blkmin ||
1464 				    number > st->blkmax)) {
1465 					error = EINVAL;
1466 					break;
1467 				}
1468 				st->flags |= ST_FIXEDBLOCKS;
1469 			}
1470 			st->blksize = number;
1471 			st->flags |= ST_BLOCK_SET;	/*XXX */
1472 			goto try_new_value;
1473 		case MTSETDNSTY:	/* Set density for device and mode */
1474 			/*
1475 			 * Any number >= 0 and <= 0xff is legal. Numbers
1476 			 * above 0x80 are 'vendor unique'.
1477 			 */
1478 			if (number < 0 || number > 255) {
1479 				error = EINVAL;
1480 				break;
1481 			} else
1482 				st->density = number;
1483 			goto try_new_value;
1484 		case MTCMPRESS:
1485 			error = st->ops(st, (number == 0) ?
1486 			    ST_OPS_CMPRSS_OFF : ST_OPS_CMPRSS_ON,
1487 			    XS_CTL_SILENT);
1488 			break;
1489 		case MTEWARN:
1490 			if (number)
1491 				st->flags |= ST_EARLYWARN;
1492 			else
1493 				st->flags &= ~ST_EARLYWARN;
1494 			break;
1495 
1496 		default:
1497 			error = EINVAL;
1498 		}
1499 		break;
1500 	}
1501 	case MTIOCIEOT:
1502 	case MTIOCEEOT:
1503 		break;
1504 	case MTIOCRDSPOS:
1505 		error = st_rdpos(st, 0, (uint32_t *)arg);
1506 		break;
1507 	case MTIOCRDHPOS:
1508 		error = st_rdpos(st, 1, (uint32_t *)arg);
1509 		break;
1510 	case MTIOCSLOCATE:
1511 		error = st_setpos(st, 0, (uint32_t *)arg);
1512 		break;
1513 	case MTIOCHLOCATE:
1514 		error = st_setpos(st, 1, (uint32_t *)arg);
1515 		break;
1516 	default:
1517 		error = scsipi_do_ioctl(st->sc_periph, dev, cmd, arg, flag, l);
1518 		break;
1519 	}
1520 	return error;
1521 
1522 try_new_value:
1523 	/*
1524 	 * Check that the mode being asked for is aggreeable to the
1525 	 * drive. If not, put it back the way it was.
1526 	 *
1527 	 * If in control mode, we can make (persistent) mode changes
1528 	 * even if no medium is loaded (see st(4)).
1529 	 */
1530 	if ((STMODE(dev) != CTRL_MODE || (st->flags & ST_MOUNTED) != 0) &&
1531 	    (error = st->ops(st, ST_OPS_MODESELECT, 0)) != 0) {
1532 		/* put it back as it was */
1533 		aprint_error_dev(st->sc_dev, "cannot set selected mode\n");
1534 		st->density = hold_density;
1535 		st->blksize = hold_blksize;
1536 		if (st->blksize)
1537 			st->flags |= ST_FIXEDBLOCKS;
1538 		else
1539 			st->flags &= ~ST_FIXEDBLOCKS;
1540 		return error;
1541 	}
1542 	/*
1543 	 * As the drive liked it, if we are setting a new default,
1544 	 * set it into the structures as such.
1545 	 *
1546 	 * The means for deciding this are not finalised yet- but
1547 	 * if the device was opened in Control Mode, the values
1548 	 * are persistent now across mounts.
1549 	 */
1550 	if (STMODE(dev) == CTRL_MODE) {
1551 		switch ((short) (mt->mt_op)) {
1552 		case MTSETBSIZ:
1553 			st->modes[dsty].blksize = st->blksize;
1554 			st->modeflags[dsty] |= BLKSIZE_SET_BY_USER;
1555 			break;
1556 		case MTSETDNSTY:
1557 			st->modes[dsty].density = st->density;
1558 			st->modeflags[dsty] |= DENSITY_SET_BY_USER;
1559 			break;
1560 		}
1561 	}
1562 	return 0;
1563 }
1564 
1565 /* Do a synchronous read. */
1566 static int
1567 st_read(struct st_softc *st, char *bf, int size, int flags)
1568 {
1569 	struct scsi_rw_tape cmd;
1570 
1571 	/* If it's a null transfer, return immediatly */
1572 	if (size == 0)
1573 		return 0;
1574 	memset(&cmd, 0, sizeof(cmd));
1575 	cmd.opcode = READ;
1576 	if (st->flags & ST_FIXEDBLOCKS) {
1577 		cmd.byte2 |= SRW_FIXED;
1578 		_lto3b(size / (st->blksize ? st->blksize : DEF_FIXED_BSIZE),
1579 		    cmd.len);
1580 	} else
1581 		_lto3b(size, cmd.len);
1582 	return scsipi_command(st->sc_periph,
1583 	    (void *)&cmd, sizeof(cmd), (void *)bf, size, 0, ST_IO_TIME, NULL,
1584 	    flags | XS_CTL_DATA_IN);
1585 }
1586 
1587 /* issue an erase command */
1588 static int
1589 st_erase(struct st_softc *st, int full, int flags)
1590 {
1591 	int tmo;
1592 	struct scsi_erase cmd;
1593 
1594 	/*
1595 	 * Full erase means set LONG bit in erase command, which asks
1596 	 * the drive to erase the entire unit.  Without this bit, we're
1597 	 * asking the drive to write an erase gap.
1598 	 */
1599 	memset(&cmd, 0, sizeof(cmd));
1600 	cmd.opcode = ERASE;
1601 	if (full) {
1602 		cmd.byte2 = SE_LONG;
1603 		tmo = ST_SPC_TIME;
1604 	} else
1605 		tmo = ST_IO_TIME;
1606 
1607 	/*
1608 	 * XXX We always do this asynchronously, for now, unless the device
1609 	 * has the ST_Q_ERASE_NOIMM quirk.  How long should we wait if we
1610 	 * want to (eventually) to it synchronously?
1611 	 */
1612 	if ((st->quirks & ST_Q_ERASE_NOIMM) == 0)
1613 		cmd.byte2 |= SE_IMMED;
1614 
1615 	return scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1616 	    ST_RETRIES, tmo, NULL, flags);
1617 }
1618 
1619 /* skip N blocks/filemarks/seq filemarks/eom */
1620 static int
1621 st_space(struct st_softc *st, int number, u_int what, int flags)
1622 {
1623 	struct scsi_space cmd;
1624 	int error;
1625 
1626 	switch (what) {
1627 	case SP_BLKS:
1628 		if (st->flags & ST_PER_ACTION) {
1629 			if (number > 0) {
1630 				st->flags &= ~ST_PER_ACTION;
1631 				return EIO;
1632 			} else if (number < 0) {
1633 				if (st->flags & ST_AT_FILEMARK) {
1634 					/*
1635 					 * Handling of ST_AT_FILEMARK
1636 					 * in st_space will fill in the
1637 					 * right file mark count.
1638 					 */
1639 					error = st_space(st, 0, SP_FILEMARKS,
1640 					    flags);
1641 					if (error)
1642 						return error;
1643 				}
1644 				if (st->flags & ST_BLANK_READ) {
1645 					st->flags &= ~ST_BLANK_READ;
1646 					return EIO;
1647 				}
1648 				st->flags &= ~(ST_EIO_PENDING|ST_EOM_PENDING);
1649 			}
1650 		}
1651 		break;
1652 	case SP_FILEMARKS:
1653 		if (st->flags & ST_EIO_PENDING) {
1654 			if (number > 0) {
1655 				/* pretend we just discovered the error */
1656 				st->flags &= ~ST_EIO_PENDING;
1657 				return EIO;
1658 			} else if (number < 0) {
1659 				/* back away from the error */
1660 				st->flags &= ~ST_EIO_PENDING;
1661 			}
1662 		}
1663 		if (st->flags & ST_AT_FILEMARK) {
1664 			st->flags &= ~ST_AT_FILEMARK;
1665 			number--;
1666 		}
1667 		if ((st->flags & ST_BLANK_READ) && (number < 0)) {
1668 			/* back away from unwritten tape */
1669 			st->flags &= ~ST_BLANK_READ;
1670 			number++;	/* XXX dubious */
1671 		}
1672 		break;
1673 	case SP_EOM:
1674 		if (st->flags & ST_EOM_PENDING) {
1675 			/* we're already there */
1676 			st->flags &= ~ST_EOM_PENDING;
1677 			return 0;
1678 		}
1679 		if (st->flags & ST_EIO_PENDING) {
1680 			/* pretend we just discovered the error */
1681 			st->flags &= ~ST_EIO_PENDING;
1682 			return EIO;
1683 		}
1684 		if (st->flags & ST_AT_FILEMARK)
1685 			st->flags &= ~ST_AT_FILEMARK;
1686 		break;
1687 	}
1688 	if (number == 0)
1689 		return 0;
1690 
1691 	memset(&cmd, 0, sizeof(cmd));
1692 	cmd.opcode = SPACE;
1693 	cmd.byte2 = what;
1694 	_lto3b(number, cmd.number);
1695 
1696 	st->flags &= ~ST_POSUPDATED;
1697 	st->last_ctl_resid = 0;
1698 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1699 	    0, ST_SPC_TIME, NULL, flags);
1700 
1701 	if (error == 0 && (st->flags & ST_POSUPDATED) == 0) {
1702 		number = number - st->last_ctl_resid;
1703 		if (what == SP_BLKS) {
1704 			if (st->blkno != -1)
1705 				st->blkno += number;
1706 		} else if (what == SP_FILEMARKS) {
1707 			if (st->fileno != -1) {
1708 				st->fileno += number;
1709 				if (number > 0)
1710 					st->blkno = 0;
1711 				else if (number < 0)
1712 					st->blkno = -1;
1713 			}
1714 		} else if (what == SP_EOM) {
1715 			/* This loses us relative position. */
1716 			st->fileno = st->blkno = -1;
1717 		}
1718 	}
1719 	return error;
1720 }
1721 
1722 /*
1723  * write N filemarks
1724  */
1725 static int
1726 st_write_filemarks(struct st_softc *st, int number, int flags)
1727 {
1728 	int error;
1729 	struct scsi_write_filemarks cmd;
1730 
1731 	/*
1732 	 * It's hard to write a negative number of file marks.
1733 	 * Don't try.
1734 	 */
1735 	if (number < 0)
1736 		return EINVAL;
1737 	switch (number) {
1738 	case 0:		/* really a command to sync the drive's buffers */
1739 		break;
1740 	case 1:
1741 		if (st->flags & ST_FM_WRITTEN)	/* already have one down */
1742 			st->flags &= ~ST_WRITTEN;
1743 		else
1744 			st->flags |= ST_FM_WRITTEN;
1745 		st->flags &= ~ST_PER_ACTION;
1746 		break;
1747 	default:
1748 		st->flags &= ~(ST_PER_ACTION | ST_WRITTEN);
1749 	}
1750 
1751 	memset(&cmd, 0, sizeof(cmd));
1752 	cmd.opcode = WRITE_FILEMARKS;
1753 	if (SCSIPI_BUSTYPE_TYPE(scsipi_periph_bustype(st->sc_periph)) ==
1754 	    SCSIPI_BUSTYPE_ATAPI)
1755 		cmd.byte2 = SR_IMMED;
1756 	/*
1757 	 * The ATAPI Onstream DI-30 doesn't support writing filemarks, but
1758 	 * WRITE_FILEMARKS is still used to flush the buffer
1759 	 */
1760 	if ((st->quirks & ST_Q_NOFILEMARKS) == 0)
1761 		_lto3b(number, cmd.number);
1762 
1763 	/* XXX WE NEED TO BE ABLE TO GET A RESIDIUAL XXX */
1764 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1765 	    0, ST_IO_TIME * 4, NULL, flags);
1766 	if (error == 0 && st->fileno != -1)
1767 		st->fileno += number;
1768 	return error;
1769 }
1770 
1771 /*
1772  * Make sure the right number of file marks is on tape if the
1773  * tape has been written.  If the position argument is true,
1774  * leave the tape positioned where it was originally.
1775  *
1776  * nmarks returns the number of marks to skip (or, if position
1777  * true, which were skipped) to get back original position.
1778  */
1779 static int
1780 st_check_eod(struct st_softc *st, boolean position, int *nmarks, int flags)
1781 {
1782 	int error;
1783 
1784 	switch (st->flags & (ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD)) {
1785 	default:
1786 		*nmarks = 0;
1787 		return 0;
1788 	case ST_WRITTEN:
1789 	case ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD:
1790 		*nmarks = 1;
1791 		break;
1792 	case ST_WRITTEN | ST_2FM_AT_EOD:
1793 		*nmarks = 2;
1794 	}
1795 	error = st_write_filemarks(st, *nmarks, flags);
1796 	if (position && !error)
1797 		error = st_space(st, -*nmarks, SP_FILEMARKS, flags);
1798 	return error;
1799 }
1800 
1801 /* load/unload/retension */
1802 static int
1803 st_load(struct st_softc *st, u_int type, int flags)
1804 {
1805 	int error;
1806 	struct scsi_load cmd;
1807 
1808 	if (type != LD_LOAD) {
1809 		int nmarks;
1810 
1811 		error = st_check_eod(st, FALSE, &nmarks, flags);
1812 		if (error) {
1813 			aprint_error_dev(st->sc_dev,
1814 			    "failed to write closing filemarks at "
1815 			    "unload, errno=%d\n", error);
1816 			return error;
1817 		}
1818 	}
1819 	if (st->quirks & ST_Q_IGNORE_LOADS) {
1820 		if (type == LD_LOAD)
1821 			/*
1822 			 * If we ignore loads, at least we should try a rewind.
1823 			 */
1824 			return st_rewind(st, 0, flags);
1825 		/* otherwise, we should do what's asked of us */
1826 	}
1827 
1828 	memset(&cmd, 0, sizeof(cmd));
1829 	cmd.opcode = LOAD;
1830 	if (SCSIPI_BUSTYPE_TYPE(scsipi_periph_bustype(st->sc_periph)) ==
1831 	    SCSIPI_BUSTYPE_ATAPI)
1832 		cmd.byte2 = SR_IMMED;
1833 	cmd.how = type;
1834 
1835 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1836 	    ST_RETRIES, ST_SPC_TIME, NULL, flags);
1837 	if (error) {
1838 		aprint_error_dev(st->sc_dev, "error %d in st_load (op %d)\n",
1839 		    error, type);
1840 	}
1841 	return error;
1842 }
1843 
1844 /* Rewind the device */
1845 static int
1846 st_rewind(struct st_softc *st, u_int immediate, int flags)
1847 {
1848 	struct scsi_rewind cmd;
1849 	int error;
1850 	int nmarks;
1851 	int timeout;
1852 
1853 	error = st_check_eod(st, FALSE, &nmarks, flags);
1854 	if (error) {
1855 		aprint_error_dev(st->sc_dev,
1856 		    "failed to write closing filemarks at "
1857 		    "rewind, errno=%d\n", error);
1858 		return error;
1859 	}
1860 	st->flags &= ~ST_PER_ACTION;
1861 
1862 	/* If requestor asked for immediate response, set a short timeout */
1863 	timeout = immediate ? ST_CTL_TIME : ST_SPC_TIME;
1864 
1865 	/* ATAPI tapes always need immediate to be set */
1866 	if (scsipi_periph_bustype(st->sc_periph) == SCSIPI_BUSTYPE_ATAPI)
1867 		immediate = SR_IMMED;
1868 
1869 	memset(&cmd, 0, sizeof(cmd));
1870 	cmd.opcode = REWIND;
1871 	cmd.byte2 = immediate;
1872 
1873 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1874 	    ST_RETRIES, timeout, NULL, flags);
1875 	if (error) {
1876 		aprint_error_dev(st->sc_dev, "error %d trying to rewind\n",
1877 		    error);
1878 		/* lost position */
1879 		st->fileno = st->blkno = -1;
1880 	} else
1881 		st->fileno = st->blkno = 0;
1882 	return error;
1883 }
1884 
1885 static int
1886 st_rdpos(struct st_softc *st, int hard, uint32_t *blkptr)
1887 {
1888 	int error;
1889 	uint8_t posdata[20];
1890 	struct scsi_tape_read_position cmd;
1891 
1892 	/*
1893 	 * We try and flush any buffered writes here if we were writing
1894 	 * and we're trying to get hardware block position. It eats
1895 	 * up performance substantially, but I'm wary of drive firmware.
1896 	 *
1897 	 * I think that *logical* block position is probably okay-
1898 	 * but hardware block position might have to wait for data
1899 	 * to hit media to be valid. Caveat Emptor.
1900 	 */
1901 
1902 	if (hard && (st->flags & ST_WRITTEN)) {
1903 		/* First flush any pending writes... */
1904 		error = st_write_filemarks(st, 0, XS_CTL_SILENT);
1905 		/*
1906 		 * The latter case is for 'write protected' tapes
1907 		 * which are too stupid to recognize a zero count
1908 		 * for writing filemarks as a no-op.
1909 		 */
1910 		if (error != 0 && error != EACCES && error != EROFS)
1911 			return error;
1912 	}
1913 
1914 	memset(&cmd, 0, sizeof(cmd));
1915 	memset(&posdata, 0, sizeof(posdata));
1916 	cmd.opcode = READ_POSITION;
1917 	if (hard)
1918 		cmd.byte1 = 1;
1919 
1920 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd),
1921 	    (void *)&posdata, sizeof(posdata), ST_RETRIES, ST_CTL_TIME, NULL,
1922 	    XS_CTL_SILENT | XS_CTL_DATA_IN);
1923 
1924 	if (error == 0) {
1925 #if	0
1926 		printf("posdata:");
1927 		for (hard = 0; hard < sizeof(posdata); hard++)
1928 			printf("%02x ", posdata[hard] & 0xff);
1929 		printf("\n");
1930 #endif
1931 		if (posdata[0] & 0x4)	/* Block Position Unknown */
1932 			error = EINVAL;
1933 		else
1934 			*blkptr = _4btol(&posdata[4]);
1935 	}
1936 	return error;
1937 }
1938 
1939 static int
1940 st_setpos(struct st_softc *st, int hard, uint32_t *blkptr)
1941 {
1942 	int error;
1943 	struct scsi_tape_locate cmd;
1944 
1945 	/*
1946 	 * We used to try and flush any buffered writes here.
1947 	 * Now we push this onto user applications to either
1948 	 * flush the pending writes themselves (via a zero count
1949 	 * WRITE FILEMARKS command) or they can trust their tape
1950 	 * drive to do this correctly for them.
1951 	 *
1952 	 * There are very ugly performance limitations otherwise.
1953 	 */
1954 
1955 	memset(&cmd, 0, sizeof(cmd));
1956 	cmd.opcode = LOCATE;
1957 	if (hard)
1958 		cmd.byte2 = 1 << 2;
1959 	_lto4b(*blkptr, cmd.blkaddr);
1960 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1961 	    ST_RETRIES, ST_SPC_TIME, NULL, 0);
1962 	/*
1963 	 * Note file && block number position now unknown (if
1964 	 * these things ever start being maintained in this driver)
1965 	 */
1966 	st->fileno = st->blkno = -1;
1967 	return error;
1968 }
1969 
1970 
1971 /*
1972  * Look at the returned sense and act on the error and determine
1973  * the unix error number to pass back..., 0 (== report no error),
1974  * -1 = retry the operation, -2 continue error processing.
1975  */
1976 static int
1977 st_interpret_sense(struct scsipi_xfer *xs)
1978 {
1979 	struct scsipi_periph *periph = xs->xs_periph;
1980 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
1981 	struct buf *bp = xs->bp;
1982 	struct st_softc *st = device_private(periph->periph_dev);
1983 	int retval = EJUSTRETURN;
1984 	int doprint = ((xs->xs_control & XS_CTL_SILENT) == 0);
1985 	uint8_t key;
1986 	int32_t info;
1987 
1988 	/*
1989 	 * If it isn't a extended or extended/deferred error, let
1990 	 * the generic code handle it.
1991 	 */
1992 	if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
1993 	    SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
1994 		return retval;
1995 
1996 	if (sense->response_code & SSD_RCODE_VALID)
1997 		info = _4btol(sense->info);
1998 	else
1999 		info = (st->flags & ST_FIXEDBLOCKS) ?
2000 		    xs->datalen / st->blksize : xs->datalen;
2001 	key = SSD_SENSE_KEY(sense->flags);
2002 	st->mt_erreg = key;
2003 	st->asc = sense->asc;
2004 	st->ascq = sense->ascq;
2005 	st->mt_resid = (short) info;
2006 
2007 	if (key == SKEY_NOT_READY && st->asc == 0x4 && st->ascq == 0x1) {
2008 		/* Not Ready, Logical Unit Is in Process Of Becoming Ready */
2009 		if (!callout_pending(&periph->periph_callout))
2010 			scsipi_periph_freeze(periph, 1);
2011 		callout_reset(&periph->periph_callout,
2012 		    hz, scsipi_periph_timed_thaw, periph);
2013 		return ERESTART;
2014 	}
2015 
2016 	/* If the device is not open yet, let generic handle */
2017 	if ((periph->periph_flags & PERIPH_OPEN) == 0)
2018 		return retval;
2019 
2020 	xs->resid = info;
2021 	if (st->flags & ST_FIXEDBLOCKS) {
2022 		if (bp) {
2023 			xs->resid *= st->blksize;
2024 			st->last_io_resid = xs->resid;
2025 		} else
2026 			st->last_ctl_resid = xs->resid;
2027 		if (key == SKEY_VOLUME_OVERFLOW) {
2028 			st->flags |= ST_EIO_PENDING;
2029 			if (bp)
2030 				bp->b_resid = xs->resid;
2031 		} else if (sense->flags & SSD_EOM) {
2032 			if ((st->flags & ST_EARLYWARN) == 0)
2033 				st->flags |= ST_EIO_PENDING;
2034 			st->flags |= ST_EOM_PENDING;
2035 			if (bp) {
2036 #if 0
2037 				bp->b_resid = xs->resid;
2038 #else
2039 				/*
2040 				 * Grotesque as it seems, the few times
2041 				 * I've actually seen a non-zero resid,
2042 				 * the tape drive actually lied and had
2043 				 * written all the data!
2044 				 */
2045 				bp->b_resid = 0;
2046 #endif
2047 			}
2048 		}
2049 		if (sense->flags & SSD_FILEMARK) {
2050 			st->flags |= ST_AT_FILEMARK;
2051 			if (bp)
2052 				bp->b_resid = xs->resid;
2053 			if (st->fileno != (daddr_t) -1) {
2054 				st->fileno++;
2055 				st->blkno = 0;
2056 				st->flags |= ST_POSUPDATED;
2057 			}
2058 		}
2059 		if (sense->flags & SSD_ILI) {
2060 			st->flags |= ST_EIO_PENDING;
2061 			if (bp)
2062 				bp->b_resid = xs->resid;
2063 			if (sense->response_code & SSD_RCODE_VALID &&
2064 			    (xs->xs_control & XS_CTL_SILENT) == 0)
2065 				aprint_error_dev(st->sc_dev,
2066 				    "block wrong size, %d blocks residual\n",
2067 				    info);
2068 
2069 			/*
2070 			 * This quirk code helps the drive read
2071 			 * the first tape block, regardless of
2072 			 * format.  That is required for these
2073 			 * drives to return proper MODE SENSE
2074 			 * information.
2075 			 */
2076 			if ((st->quirks & ST_Q_SENSE_HELP) &&
2077 			    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
2078 				st->blksize -= 512;
2079 			else if ((st->flags & ST_POSUPDATED) == 0) {
2080 				if (st->blkno != (daddr_t) -1) {
2081 					st->blkno +=
2082 					    (xs->datalen / st->blksize);
2083 					st->flags |= ST_POSUPDATED;
2084 				}
2085 			}
2086 		}
2087 		/*
2088 		 * If data wanted and no data was transferred, do it immediately
2089 		 */
2090 		if (xs->datalen && xs->resid >= xs->datalen) {
2091 			if (st->flags & ST_EIO_PENDING)
2092 				return EIO;
2093 			if (st->flags & ST_AT_FILEMARK) {
2094 				if (bp)
2095 					bp->b_resid = xs->resid;
2096 				return 0;
2097 			}
2098 		}
2099 	} else {		/* must be variable mode */
2100 		if (bp)
2101 			st->last_io_resid = xs->resid;
2102 		else
2103 			st->last_ctl_resid = xs->resid;
2104 		if (sense->flags & SSD_EOM) {
2105 			/*
2106 			 * The current semantics of this
2107 			 * driver requires EOM detection
2108 			 * to return EIO unless early
2109 			 * warning detection is enabled
2110 			 * for variable mode (this is always
2111 			 * on for fixed block mode).
2112 			 */
2113 			if (st->flags & ST_EARLYWARN) {
2114 				st->flags |= ST_EOM_PENDING;
2115 				retval = 0;
2116 			} else {
2117 				retval = EIO;
2118 				/*
2119 				 * If we return an error we can't claim to
2120 				 * have transfered all data.
2121 				 */
2122 				if (xs->resid == 0)
2123 					xs->resid = xs->datalen;
2124 			}
2125 
2126 			/*
2127 			 * If it's an unadorned EOM detection,
2128 			 * suppress printing an error.
2129 			 */
2130 			if (key == SKEY_NO_SENSE) {
2131 				doprint = 0;
2132 			}
2133 		} else if (sense->flags & SSD_FILEMARK) {
2134 			retval = 0;
2135 			if (st->fileno != (daddr_t) -1) {
2136 				st->fileno++;
2137 				st->blkno = 0;
2138 				st->flags |= ST_POSUPDATED;
2139 			}
2140 		} else if (sense->flags & SSD_ILI) {
2141 			if (info < 0) {
2142 				/*
2143 				 * The tape record was bigger than the read
2144 				 * we issued.
2145 				 */
2146 				if ((xs->xs_control & XS_CTL_SILENT) == 0) {
2147 					aprint_error_dev(st->sc_dev,
2148 					    "%d-byte tape record too big"
2149 					    " for %d-byte user buffer\n",
2150 					    xs->datalen - info, xs->datalen);
2151 				}
2152 				retval = EIO;
2153 			} else {
2154 				retval = 0;
2155 				if (st->blkno != (daddr_t) -1) {
2156 					st->blkno++;
2157 					st->flags |= ST_POSUPDATED;
2158 				}
2159 			}
2160 		}
2161 		if (bp)
2162 			bp->b_resid = xs->resid;
2163 	}
2164 
2165 #ifndef SCSIPI_DEBUG
2166 	if (retval == 0 && key == SKEY_NO_SENSE)
2167 		doprint = 0;
2168 #endif
2169 	if (key == SKEY_BLANK_CHECK) {
2170 		/*
2171 		 * This quirk code helps the drive read the
2172 		 * first tape block, regardless of format.  That
2173 		 * is required for these drives to return proper
2174 		 * MODE SENSE information.
2175 		 */
2176 		if ((st->quirks & ST_Q_SENSE_HELP) &&
2177 		    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0) {
2178 			/* still starting */
2179 			st->blksize -= 512;
2180 		} else if (!(st->flags & (ST_2FM_AT_EOD | ST_BLANK_READ))) {
2181 			st->flags |= ST_BLANK_READ;
2182 			xs->resid = xs->datalen;
2183 			if (bp) {
2184 				bp->b_resid = xs->resid;
2185 				/* return an EOF */
2186 			}
2187 			retval = 0;
2188 			/* lost position */
2189 			st->fileno = st->blkno = -1;
2190 		}
2191 	}
2192 
2193 	/*
2194 	 * If generic sense processing will continue, we should not
2195 	 * print sense info here.
2196 	 */
2197 	if (retval == EJUSTRETURN)
2198 		doprint = 0;
2199 
2200 	if (doprint) {
2201 		/* Print verbose sense info if possible */
2202 		if (scsipi_print_sense(xs, 0) != 0)
2203 			return retval;
2204 
2205 		/* Print less-verbose sense info */
2206 		scsipi_printaddr(periph);
2207 		printf("Sense Key 0x%02x", key);
2208 		if ((sense->response_code & SSD_RCODE_VALID) != 0) {
2209 			switch (key) {
2210 			case SKEY_NOT_READY:
2211 			case SKEY_ILLEGAL_REQUEST:
2212 			case SKEY_UNIT_ATTENTION:
2213 			case SKEY_DATA_PROTECT:
2214 				break;
2215 			case SKEY_VOLUME_OVERFLOW:
2216 			case SKEY_BLANK_CHECK:
2217 				printf(", requested size: %d (decimal)", info);
2218 				break;
2219 			case SKEY_ABORTED_COMMAND:
2220 				if (xs->xs_retries)
2221 					printf(", retrying");
2222 				printf(", cmd 0x%x, info 0x%x",
2223 				    xs->cmd->opcode, info);
2224 				break;
2225 			default:
2226 				printf(", info = %d (decimal)", info);
2227 			}
2228 		}
2229 		if (sense->extra_len != 0) {
2230 			int n;
2231 			printf(", data =");
2232 			for (n = 0; n < sense->extra_len; n++)
2233 				printf(" %02x", sense->csi[n]);
2234 		}
2235 		printf("\n");
2236 	}
2237 	return retval;
2238 }
2239 
2240 /*
2241  * The quirk here is that the drive returns some value to st_mode_sense
2242  * incorrectly until the tape has actually passed by the head.
2243  *
2244  * The method is to set the drive to large fixed-block state (user-specified
2245  * density and 1024-byte blocks), then read and rewind to get it to sense the
2246  * tape.  If that doesn't work, try 512-byte fixed blocks.  If that doesn't
2247  * work, as a last resort, try variable- length blocks.  The result will be
2248  * the ability to do an accurate st_mode_sense.
2249  *
2250  * We know we can do a rewind because we just did a load, which implies rewind.
2251  * Rewind seems preferable to space backward if we have a virgin tape.
2252  *
2253  * The rest of the code for this quirk is in ILI processing and BLANK CHECK
2254  * error processing, both part of st_interpret_sense.
2255  */
2256 static int
2257 st_touch_tape(struct st_softc *st)
2258 {
2259 	char *bf;
2260 	int readsize;
2261 	int error;
2262 
2263 	bf = malloc(1024, M_TEMP, M_NOWAIT);
2264 	if (bf == NULL)
2265 		return ENOMEM;
2266 
2267 	if ((error = st->ops(st, ST_OPS_MODESENSE, 0)) != 0)
2268 		goto bad;
2269 
2270 	/*
2271 	 * If the block size is already known from the
2272 	 * sense data, use it. Else start probing at 1024.
2273 	 */
2274 	if (st->media_blksize > 0)
2275 		st->blksize = st->media_blksize;
2276 	else
2277 		st->blksize = 1024;
2278 
2279 	do {
2280 		switch (st->blksize) {
2281 		case 512:
2282 		case 1024:
2283 			readsize = st->blksize;
2284 			st->flags |= ST_FIXEDBLOCKS;
2285 			break;
2286 		default:
2287 			readsize = 1;
2288 			st->flags &= ~ST_FIXEDBLOCKS;
2289 		}
2290 		if ((error = st->ops(st, ST_OPS_MODESELECT, XS_CTL_SILENT))
2291 		    != 0) {
2292 			/*
2293 			 * The device did not agree with the proposed
2294 			 * block size. If we exhausted our options,
2295 			 * return failure, else try another.
2296 			 */
2297 			if (readsize == 1)
2298 				goto bad;
2299 			st->blksize -= 512;
2300 			continue;
2301 		}
2302 		st_read(st, bf, readsize, XS_CTL_SILENT);	/* XXX */
2303 		if ((error = st_rewind(st, 0, 0)) != 0) {
2304 bad:			free(bf, M_TEMP);
2305 			return error;
2306 		}
2307 	} while (readsize != 1 && readsize > st->blksize);
2308 
2309 	free(bf, M_TEMP);
2310 	return 0;
2311 }
2312 
2313 static int
2314 stdump(dev_t dev, daddr_t blkno, void *va, size_t size)
2315 {
2316 	/* Not implemented. */
2317 	return ENXIO;
2318 }
2319 
2320 /*
2321  * Send a filled out parameter structure to the drive to
2322  * set it into the desire modes etc.
2323  */
2324 int
2325 st_mode_select(struct st_softc *st, int flags)
2326 {
2327 	u_int select_len;
2328 	struct select {
2329 		struct scsi_mode_parameter_header_6 header;
2330 		struct scsi_general_block_descriptor blk_desc;
2331 		u_char sense_data[MAX_PAGE_0_SIZE];
2332 	} select;
2333 	struct scsipi_periph *periph = st->sc_periph;
2334 
2335 	select_len = sizeof(select.header) + sizeof(select.blk_desc) +
2336 		     st->page_0_size;
2337 
2338 	/*
2339 	 * This quirk deals with drives that have only one valid mode
2340 	 * and think this gives them license to reject all mode selects,
2341 	 * even if the selected mode is the one that is supported.
2342 	 */
2343 	if (st->quirks & ST_Q_UNIMODAL) {
2344 		SC_DEBUG(periph, SCSIPI_DB3,
2345 		    ("not setting density 0x%x blksize 0x%x\n",
2346 		    st->density, st->blksize));
2347 		return 0;
2348 	}
2349 
2350 	/* Set up for a mode select */
2351 	memset(&select, 0, sizeof(select));
2352 	select.header.blk_desc_len = sizeof(struct
2353 	    scsi_general_block_descriptor);
2354 	select.header.dev_spec &= ~SMH_DSP_BUFF_MODE;
2355 	select.blk_desc.density = st->density;
2356 	if (st->flags & ST_DONTBUFFER)
2357 		select.header.dev_spec |= SMH_DSP_BUFF_MODE_OFF;
2358 	else
2359 		select.header.dev_spec |= SMH_DSP_BUFF_MODE_ON;
2360 	if (st->flags & ST_FIXEDBLOCKS)
2361 		_lto3b(st->blksize, select.blk_desc.blklen);
2362 	if (st->page_0_size)
2363 		memcpy(select.sense_data, st->sense_data, st->page_0_size);
2364 
2365 	/* do the command */
2366 	return scsipi_mode_select(periph, 0, &select.header, select_len,
2367 				  flags, ST_RETRIES, ST_CTL_TIME);
2368 }
2369