xref: /netbsd-src/sys/dev/scsipi/st.c (revision c9496f6b604074a9451a67df576a5b423068e71e)
1 /*	$NetBSD: st.c,v 1.231 2017/06/17 22:35:50 mlelstv 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 1.231 2017/06/17 22:35:50 mlelstv Exp $");
54 
55 #ifdef _KERNEL_OPT
56 #include "opt_scsi.h"
57 #endif
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/fcntl.h>
62 #include <sys/errno.h>
63 #include <sys/ioctl.h>
64 #include <sys/malloc.h>
65 #include <sys/buf.h>
66 #include <sys/bufq.h>
67 #include <sys/proc.h>
68 #include <sys/mtio.h>
69 #include <sys/device.h>
70 #include <sys/conf.h>
71 #include <sys/kernel.h>
72 #include <sys/vnode.h>
73 #include <sys/iostat.h>
74 #include <sys/sysctl.h>
75 
76 #include <dev/scsipi/scsi_spc.h>
77 #include <dev/scsipi/scsipi_all.h>
78 #include <dev/scsipi/scsi_all.h>
79 #include <dev/scsipi/scsi_tape.h>
80 #include <dev/scsipi/scsipiconf.h>
81 #include <dev/scsipi/scsipi_base.h>
82 #include <dev/scsipi/stvar.h>
83 
84 /* Defines for device specific stuff */
85 #define DEF_FIXED_BSIZE  512
86 
87 #define STMODE(z)	( minor(z)       & 0x03)
88 #define STDSTY(z)	((minor(z) >> 2) & 0x03)
89 #define STUNIT(z)	((minor(z) >> 4)       )
90 #define STNMINOR	16
91 
92 #define NORMAL_MODE	0
93 #define NOREW_MODE	1
94 #define EJECT_MODE	2
95 #define CTRL_MODE	3
96 
97 #ifndef		ST_MOUNT_DELAY
98 #define		ST_MOUNT_DELAY		0
99 #endif
100 
101 static dev_type_open(stopen);
102 static dev_type_close(stclose);
103 static dev_type_read(stread);
104 static dev_type_write(stwrite);
105 static dev_type_ioctl(stioctl);
106 static dev_type_strategy(ststrategy);
107 static dev_type_dump(stdump);
108 
109 const struct bdevsw st_bdevsw = {
110 	.d_open = stopen,
111 	.d_close = stclose,
112 	.d_strategy = ststrategy,
113 	.d_ioctl = stioctl,
114 	.d_dump = stdump,
115 	.d_psize = nosize,
116 	.d_discard = nodiscard,
117 	.d_flag = D_TAPE | D_MPSAFE
118 };
119 
120 const struct cdevsw st_cdevsw = {
121 	.d_open = stopen,
122 	.d_close = stclose,
123 	.d_read = stread,
124 	.d_write = stwrite,
125 	.d_ioctl = stioctl,
126 	.d_stop = nostop,
127 	.d_tty = notty,
128 	.d_poll = nopoll,
129 	.d_mmap = nommap,
130 	.d_kqfilter = nokqfilter,
131 	.d_discard = nodiscard,
132 	.d_flag = D_TAPE | D_MPSAFE
133 };
134 
135 /*
136  * Define various devices that we know mis-behave in some way,
137  * and note how they are bad, so we can correct for them
138  */
139 
140 static const struct st_quirk_inquiry_pattern st_quirk_patterns[] = {
141 	{{T_SEQUENTIAL, T_REMOV,
142 	 "        ", "                ", "    "}, {0, 0, {
143 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
144 		{ST_Q_FORCE_BLKSIZE, 512, QIC_24},	/* minor 4-7 */
145 		{ST_Q_FORCE_BLKSIZE, 0, HALFINCH_1600},	/* minor 8-11 */
146 		{ST_Q_FORCE_BLKSIZE, 0, HALFINCH_6250}	/* minor 12-15 */
147 	}}},
148 	{{T_SEQUENTIAL, T_REMOV,
149 	 "TANDBERG", " TDC 3600       ", ""},     {0, 12, {
150 		{0, 0, 0},				/* minor 0-3 */
151 		{ST_Q_FORCE_BLKSIZE, 0, QIC_525},	/* minor 4-7 */
152 		{0, 0, QIC_150},			/* minor 8-11 */
153 		{0, 0, QIC_120}				/* minor 12-15 */
154 	}}},
155  	{{T_SEQUENTIAL, T_REMOV,
156  	 "TANDBERG", " TDC 3800       ", ""},     {0, 0, {
157 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
158 		{0, 0, QIC_525},			/* minor 4-7 */
159 		{0, 0, QIC_150},			/* minor 8-11 */
160 		{0, 0, QIC_120}				/* minor 12-15 */
161 	}}},
162 	{{T_SEQUENTIAL, T_REMOV,
163 	  "TANDBERG", " SLR5 4/8GB     ", ""},     {0, 0, {
164 		{ST_Q_FORCE_BLKSIZE, 1024, 0},		/* minor 0-3 */
165 		{0, 0, 0},				/* minor 4-7 */
166 		{0, 0, 0},				/* minor 8-11 */
167 		{0, 0, 0}				/* minor 12-15 */
168 	}}},
169 	/*
170 	 * lacking a manual for the 4200, it's not clear what the
171 	 * specific density codes should be- the device is a 2.5GB
172 	 * capable QIC drive, those density codes aren't readily
173 	 * availabel. The 'default' will just have to do.
174 	 */
175  	{{T_SEQUENTIAL, T_REMOV,
176  	 "TANDBERG", " TDC 4200       ", ""},     {0, 0, {
177 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
178 		{0, 0, QIC_525},			/* minor 4-7 */
179 		{0, 0, QIC_150},			/* minor 8-11 */
180 		{0, 0, QIC_120}				/* minor 12-15 */
181 	}}},
182 	/*
183 	 * At least -005 and -007 need this.  I'll assume they all do unless I
184 	 * hear otherwise.  - mycroft, 31MAR1994
185 	 */
186 	{{T_SEQUENTIAL, T_REMOV,
187 	 "ARCHIVE ", "VIPER 2525 25462", ""},     {0, 0, {
188 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
189 		{ST_Q_SENSE_HELP, 0, QIC_525},		/* minor 4-7 */
190 		{0, 0, QIC_150},			/* minor 8-11 */
191 		{0, 0, QIC_120}				/* minor 12-15 */
192 	}}},
193 	/*
194 	 * One user reports that this works for his tape drive.  It probably
195 	 * needs more work.  - mycroft, 09APR1994
196 	 */
197 	{{T_SEQUENTIAL, T_REMOV,
198 	 "SANKYO  ", "CP525           ", ""},    {0, 0, {
199 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
200 		{ST_Q_FORCE_BLKSIZE, 512, QIC_525},	/* minor 4-7 */
201 		{0, 0, QIC_150},			/* minor 8-11 */
202 		{0, 0, QIC_120}				/* minor 12-15 */
203 	}}},
204 	{{T_SEQUENTIAL, T_REMOV,
205 	 "ANRITSU ", "DMT780          ", ""},     {0, 0, {
206 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
207 		{ST_Q_FORCE_BLKSIZE, 512, QIC_525},	/* minor 4-7 */
208 		{0, 0, QIC_150},			/* minor 8-11 */
209 		{0, 0, QIC_120}				/* minor 12-15 */
210 	}}},
211 	{{T_SEQUENTIAL, T_REMOV,
212 	 "ARCHIVE ", "VIPER 150  21247", ""},     {ST_Q_ERASE_NOIMM, 12, {
213 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
214 		{0, 0, QIC_150},			/* minor 4-7 */
215 		{0, 0, QIC_120},			/* minor 8-11 */
216 		{0, 0, QIC_24}				/* minor 12-15 */
217 	}}},
218 	{{T_SEQUENTIAL, T_REMOV,
219 	 "ARCHIVE ", "VIPER 150  21531", ""},     {ST_Q_ERASE_NOIMM, 12, {
220 		{ST_Q_SENSE_HELP, 0, 0},		/* minor 0-3 */
221 		{0, 0, QIC_150},			/* minor 4-7 */
222 		{0, 0, QIC_120},			/* minor 8-11 */
223 		{0, 0, QIC_24}				/* minor 12-15 */
224 	}}},
225 	{{T_SEQUENTIAL, T_REMOV,
226 	 "WANGTEK ", "5099ES SCSI", ""},          {0, 0, {
227 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
228 		{0, 0, QIC_11},				/* minor 4-7 */
229 		{0, 0, QIC_24},				/* minor 8-11 */
230 		{0, 0, QIC_24}				/* minor 12-15 */
231 	}}},
232 	{{T_SEQUENTIAL, T_REMOV,
233 	 "WANGTEK ", "5150ES SCSI", ""},          {0, 0, {
234 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
235 		{0, 0, QIC_24},				/* minor 4-7 */
236 		{0, 0, QIC_120},			/* minor 8-11 */
237 		{0, 0, QIC_150}				/* minor 12-15 */
238 	}}},
239 	{{T_SEQUENTIAL, T_REMOV,
240 	 "WANGTEK ", "5525ES SCSI REV7", ""},     {0, 0, {
241 		{0, 0, 0},				/* minor 0-3 */
242 		{ST_Q_BLKSIZE, 0, QIC_525},		/* minor 4-7 */
243 		{0, 0, QIC_150},			/* minor 8-11 */
244 		{0, 0, QIC_120}				/* minor 12-15 */
245 	}}},
246 	{{T_SEQUENTIAL, T_REMOV,
247 	 "WangDAT ", "Model 1300      ", ""},     {0, 0, {
248 		{0, 0, 0},				/* minor 0-3 */
249 		{ST_Q_FORCE_BLKSIZE, 512, DDS},		/* minor 4-7 */
250 		{ST_Q_FORCE_BLKSIZE, 1024, DDS},	/* minor 8-11 */
251 		{ST_Q_FORCE_BLKSIZE, 0, DDS}		/* minor 12-15 */
252 	}}},
253 	{{T_SEQUENTIAL, T_REMOV,
254 	 "EXABYTE ", "EXB-8200        ", "263H"}, {0, 5, {
255 		{0, 0, 0},				/* minor 0-3 */
256 		{0, 0, 0},				/* minor 4-7 */
257 		{0, 0, 0},				/* minor 8-11 */
258 		{0, 0, 0}				/* minor 12-15 */
259 	}}},
260 	{{T_SEQUENTIAL, T_REMOV,
261 	 "STK",      "9490",             ""},
262 				{ST_Q_FORCE_BLKSIZE, 0, {
263 		{0, 0, 0},				/* minor 0-3 */
264 		{0, 0, 0},				/* minor 4-7 */
265 		{0, 0, 0},				/* minor 8-11 */
266 		{0, 0, 0}				/* minor 12-15 */
267 	}}},
268 	{{T_SEQUENTIAL, T_REMOV,
269 	 "STK",      "SD-3",             ""},
270 				{ST_Q_FORCE_BLKSIZE, 0, {
271 		{0, 0, 0},				/* minor 0-3 */
272 		{0, 0, 0},				/* minor 4-7 */
273 		{0, 0, 0},				/* minor 8-11 */
274 		{0, 0, 0}				/* minor 12-15 */
275 	}}},
276 	{{T_SEQUENTIAL, T_REMOV,
277 	 "IBM",      "03590",            ""},     {ST_Q_IGNORE_LOADS, 0, {
278 		{0, 0, 0},				/* minor 0-3 */
279 		{0, 0, 0},				/* minor 4-7 */
280 		{0, 0, 0},				/* minor 8-11 */
281 		{0, 0, 0}				/* minor 12-15 */
282 	}}},
283 	{{T_SEQUENTIAL, T_REMOV,
284 	 "HP      ", "T4000s          ", ""},     {ST_Q_UNIMODAL, 0, {
285 		{0, 0, QIC_3095},			/* minor 0-3 */
286 		{0, 0, QIC_3095},			/* minor 4-7 */
287 		{0, 0, QIC_3095},			/* minor 8-11 */
288 		{0, 0, QIC_3095},			/* minor 12-15 */
289 	}}},
290 #if 0
291 	{{T_SEQUENTIAL, T_REMOV,
292 	 "EXABYTE ", "EXB-8200        ", ""},     {0, 12, {
293 		{0, 0, 0},				/* minor 0-3 */
294 		{0, 0, 0},				/* minor 4-7 */
295 		{0, 0, 0},				/* minor 8-11 */
296 		{0, 0, 0}				/* minor 12-15 */
297 	}}},
298 #endif
299 	{{T_SEQUENTIAL, T_REMOV,
300 	 "TEAC    ", "MT-2ST/N50      ", ""},     {ST_Q_IGNORE_LOADS, 0, {
301 		{0, 0, 0},			        /* minor 0-3 */
302 		{0, 0, 0},			        /* minor 4-7 */
303 		{0, 0, 0},			        /* minor 8-11 */
304 		{0, 0, 0}			        /* minor 12-15 */
305 	}}},
306 	{{T_SEQUENTIAL, T_REMOV,
307 	 "OnStream", "ADR50 Drive", ""},	  {ST_Q_UNIMODAL, 0, {
308 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 0-3 */
309 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 4-7 */
310 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 8-11 */
311 		{ST_Q_FORCE_BLKSIZE, 512, 0},	        /* minor 12-15 */
312 	}}},
313 	{{T_SEQUENTIAL, T_REMOV,
314 	 "OnStream DI-30",      "",   "1.0"},  {ST_Q_NOFILEMARKS, 0, {
315 		{0, 0, 0},                              /* minor 0-3 */
316 		{0, 0, 0},                              /* minor 4-7 */
317 		{0, 0, 0},                              /* minor 8-11 */
318 		{0, 0, 0}                               /* minor 12-15 */
319 	}}},
320 	{{T_SEQUENTIAL, T_REMOV,
321 	 "NCR H621", "0-STD-03-46F880 ", ""},     {ST_Q_NOPREVENT, 0, {
322 		{0, 0, 0},			       /* minor 0-3 */
323 		{0, 0, 0},			       /* minor 4-7 */
324 		{0, 0, 0},			       /* minor 8-11 */
325 		{0, 0, 0}			       /* minor 12-15 */
326 	}}},
327 	{{T_SEQUENTIAL, T_REMOV,
328 	 "Seagate STT3401A", "hp0atxa", ""},	{0, 0, {
329 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 0-3 */
330 		{ST_Q_FORCE_BLKSIZE, 1024, 0},		/* minor 4-7 */
331 		{ST_Q_FORCE_BLKSIZE, 512, 0},		/* minor 8-11 */
332 		{ST_Q_FORCE_BLKSIZE, 512, 0}		/* minor 12-15 */
333 	}}},
334 };
335 
336 #define NOEJECT 0
337 #define EJECT 1
338 
339 static void	st_identify_drive(struct st_softc *,
340 		    struct scsipi_inquiry_pattern *);
341 static void	st_loadquirks(struct st_softc *);
342 static int	st_mount_tape(dev_t, int);
343 static void	st_unmount(struct st_softc *, boolean);
344 static int	st_decide_mode(struct st_softc *, boolean);
345 static void	ststart(struct scsipi_periph *);
346 static void	strestart(void *);
347 static void	stdone(struct scsipi_xfer *, int);
348 static int	st_read(struct st_softc *, char *, int, int);
349 static int	st_space(struct st_softc *, int, u_int, int);
350 static int	st_write_filemarks(struct st_softc *, int, int);
351 static int	st_check_eod(struct st_softc *, boolean, int *, int);
352 static int	st_load(struct st_softc *, u_int, int);
353 static int	st_rewind(struct st_softc *, u_int, int);
354 static int	st_interpret_sense(struct scsipi_xfer *);
355 static int	st_touch_tape(struct st_softc *);
356 static int	st_erase(struct st_softc *, int full, int flags);
357 static int	st_rdpos(struct st_softc *, int, uint32_t *);
358 static int	st_setpos(struct st_softc *, int, uint32_t *);
359 
360 static const struct scsipi_periphsw st_switch = {
361 	st_interpret_sense,
362 	ststart,
363 	NULL,
364 	stdone
365 };
366 
367 #if defined(ST_ENABLE_EARLYWARN)
368 #define	ST_INIT_FLAGS	ST_EARLYWARN
369 #else
370 #define	ST_INIT_FLAGS	0
371 #endif
372 
373 /*
374  * The routine called by the low level scsi routine when it discovers
375  * A device suitable for this driver
376  */
377 void
378 stattach(device_t parent, device_t self, void *aux)
379 {
380 	struct st_softc *st = device_private(self);
381 	struct scsipibus_attach_args *sa = aux;
382 	struct scsipi_periph *periph = sa->sa_periph;
383 
384 	SC_DEBUG(periph, SCSIPI_DB2, ("stattach: "));
385 	st->sc_dev = self;
386 
387 	/* Store information needed to contact our base driver */
388 	st->sc_periph = periph;
389 	periph->periph_dev = st->sc_dev;
390 	periph->periph_switch = &st_switch;
391 
392 	/* Set initial flags  */
393 	st->flags = ST_INIT_FLAGS;
394 
395 	/* Set up the buf queue for this device */
396 	bufq_alloc(&st->buf_queue, "fcfs", 0);
397 	callout_init(&st->sc_callout, 0);
398 
399 	/*
400 	 * Check if the drive is a known criminal and take
401 	 * Any steps needed to bring it into line
402 	 */
403 	st_identify_drive(st, &sa->sa_inqbuf);
404 	aprint_naive("\n");
405 	aprint_normal("\n");
406 	/* Use the subdriver to request information regarding the drive.  */
407 	aprint_normal_dev(self, "%s", st->quirkdata ? "quirks apply, " : "");
408 	if (scsipi_test_unit_ready(periph,
409 	    XS_CTL_DISCOVERY | XS_CTL_SILENT | XS_CTL_IGNORE_MEDIA_CHANGE) ||
410 	    st->ops(st, ST_OPS_MODESENSE,
411 	    XS_CTL_DISCOVERY | XS_CTL_SILENT | XS_CTL_IGNORE_MEDIA_CHANGE))
412 		aprint_normal("drive empty\n");
413 	else {
414 		aprint_normal("density code %d, ", st->media_density);
415 		if (st->media_blksize > 0)
416 			aprint_normal("%d-byte", st->media_blksize);
417 		else
418 			aprint_normal("variable");
419 		aprint_normal(" blocks, write-%s\n",
420 		    (st->flags & ST_READONLY) ? "protected" : "enabled");
421 	}
422 
423 	st->stats = iostat_alloc(IOSTAT_TAPE, parent,
424 	    device_xname(st->sc_dev));
425 
426 	rnd_attach_source(&st->rnd_source, device_xname(st->sc_dev),
427 	    RND_TYPE_TAPE, RND_FLAG_DEFAULT);
428 }
429 
430 int
431 stdetach(device_t self, int flags)
432 {
433 	struct st_softc *st = device_private(self);
434 	struct scsipi_periph *periph = st->sc_periph;
435 	struct scsipi_channel *chan = periph->periph_channel;
436 	int bmaj, cmaj, mn;
437 
438 	/* locate the major number */
439 	bmaj = bdevsw_lookup_major(&st_bdevsw);
440 	cmaj = cdevsw_lookup_major(&st_cdevsw);
441 
442 	/* kill any pending restart */
443 	callout_halt(&st->sc_callout, NULL);
444 
445 	mutex_enter(chan_mtx(chan));
446 
447 	/* Kill off any queued buffers. */
448 	bufq_drain(st->buf_queue);
449 
450 	/* Kill off any pending commands. */
451 	scsipi_kill_pending(st->sc_periph);
452 
453 	mutex_exit(chan_mtx(chan));
454 
455 	bufq_free(st->buf_queue);
456 
457 	/* Nuke the vnodes for any open instances */
458 	mn = STUNIT(device_unit(self));
459 	vdevgone(bmaj, mn, mn+STNMINOR-1, VBLK);
460 	vdevgone(cmaj, mn, mn+STNMINOR-1, VCHR);
461 
462 	iostat_free(st->stats);
463 
464 	/* Unhook the entropy source. */
465 	rnd_detach_source(&st->rnd_source);
466 
467 	return 0;
468 }
469 
470 /*
471  * Use the inquiry routine in 'scsi_base' to get drive info so we can
472  * Further tailor our behaviour.
473  */
474 static void
475 st_identify_drive(struct st_softc *st, struct scsipi_inquiry_pattern *inqbuf)
476 {
477 	const struct st_quirk_inquiry_pattern *finger;
478 	int priority;
479 
480 	finger = scsipi_inqmatch(inqbuf,
481 	    st_quirk_patterns,
482 	    sizeof(st_quirk_patterns) / sizeof(st_quirk_patterns[0]),
483 	    sizeof(st_quirk_patterns[0]), &priority);
484 	if (priority != 0) {
485 		st->quirkdata = &finger->quirkdata;
486 		st->drive_quirks = finger->quirkdata.quirks;
487 		st->quirks = finger->quirkdata.quirks;	/* start value */
488 		st->page_0_size = finger->quirkdata.page_0_size;
489 		KASSERT(st->page_0_size <= MAX_PAGE_0_SIZE);
490 		st_loadquirks(st);
491 	}
492 }
493 
494 /*
495  * initialise the subdevices to the default (QUIRK) state.
496  * this will remove any setting made by the system operator or previous
497  * operations.
498  */
499 static void
500 st_loadquirks(struct st_softc *st)
501 {
502 	const struct	modes *mode;
503 	struct	modes *mode2;
504 	int i;
505 
506 	mode = st->quirkdata->modes;
507 	mode2 = st->modes;
508 	for (i = 0; i < 4; i++) {
509 		memset(mode2, 0, sizeof(struct modes));
510 		st->modeflags[i] &= ~(BLKSIZE_SET_BY_QUIRK |
511 		    DENSITY_SET_BY_QUIRK | BLKSIZE_SET_BY_USER |
512 		    DENSITY_SET_BY_USER);
513 		if ((mode->quirks | st->drive_quirks) & ST_Q_FORCE_BLKSIZE) {
514 			mode2->blksize = mode->blksize;
515 			st->modeflags[i] |= BLKSIZE_SET_BY_QUIRK;
516 		}
517 		if (mode->density) {
518 			mode2->density = mode->density;
519 			st->modeflags[i] |= DENSITY_SET_BY_QUIRK;
520 		}
521 		mode2->quirks |= mode->quirks;
522 		mode++;
523 		mode2++;
524 	}
525 }
526 
527 /* open the device. */
528 static int
529 stopen(dev_t dev, int flags, int mode, struct lwp *l)
530 {
531 	u_int stmode, dsty;
532 	int error, sflags, unit, tries, ntries;
533 	struct st_softc *st;
534 	struct scsipi_periph *periph;
535 	struct scsipi_adapter *adapt;
536 
537 	unit = STUNIT(dev);
538 	st = device_lookup_private(&st_cd, unit);
539 	if (st == NULL)
540 		return ENXIO;
541 
542 	stmode = STMODE(dev);
543 	dsty = STDSTY(dev);
544 
545 	periph = st->sc_periph;
546 	adapt = periph->periph_channel->chan_adapter;
547 
548 	SC_DEBUG(periph, SCSIPI_DB1,
549 	    ("open: dev=0x%"PRIx64" (unit %d (of %d))\n", dev, unit,
550 	    st_cd.cd_ndevs));
551 
552 	/* Only allow one at a time */
553 	if (periph->periph_flags & PERIPH_OPEN) {
554 		aprint_error_dev(st->sc_dev, "already open\n");
555 		return EBUSY;
556 	}
557 
558 	if ((error = scsipi_adapter_addref(adapt)) != 0)
559 		return error;
560 
561 	/* clear any latched errors. */
562 	st->mt_resid = 0;
563 	st->mt_erreg = 0;
564 	st->asc = 0;
565 	st->ascq = 0;
566 
567 	/*
568 	 * Catch any unit attention errors. Be silent about this
569 	 * unless we're already mounted. We ignore media change
570 	 * if we're in control mode or not mounted yet.
571 	 */
572 	if ((st->flags & ST_MOUNTED) == 0 || stmode == CTRL_MODE) {
573 #ifdef SCSIDEBUG
574 		sflags = XS_CTL_IGNORE_MEDIA_CHANGE;
575 #else
576 		sflags = XS_CTL_SILENT|XS_CTL_IGNORE_MEDIA_CHANGE;
577 #endif
578 	} else
579 		sflags = 0;
580 
581 	/*
582 	 * If we're already mounted or we aren't configured for
583 	 * a mount delay, only try a test unit ready once. Otherwise,
584 	 * try up to ST_MOUNT_DELAY times with a rest interval of
585 	 * one second between each try.
586 	 */
587 	if ((st->flags & ST_MOUNTED) || ST_MOUNT_DELAY == 0)
588 		ntries = 1;
589 	else
590 		ntries = ST_MOUNT_DELAY;
591 
592 	for (error = tries = 0; tries < ntries; tries++) {
593 		int slpintr, oflags;
594 
595 		/*
596 		 * If we had no error, or we're opening the control mode
597 		 * device, we jump out right away.
598 		 */
599 		error = scsipi_test_unit_ready(periph, sflags);
600 		if (error == 0 || stmode == CTRL_MODE)
601 			break;
602 
603 		/*
604 		 * We had an error.
605 		 *
606 		 * If we're already mounted or we aren't configured for
607 		 * a mount delay, or the error isn't a NOT READY error,
608 		 * skip to the error exit now.
609 		 */
610 		if ((st->flags & ST_MOUNTED) || ST_MOUNT_DELAY == 0 ||
611 		    (st->mt_key != SKEY_NOT_READY)) {
612 			goto bad;
613 		}
614 
615 		/* clear any latched errors. */
616 		st->mt_resid = 0;
617 		st->mt_erreg = 0;
618 		st->asc = 0;
619 		st->ascq = 0;
620 
621 		/*
622 		 * Fake that we have the device open so
623 		 * we block other apps from getting in.
624 		 */
625 		oflags = periph->periph_flags;
626 		periph->periph_flags |= PERIPH_OPEN;
627 
628 		slpintr = kpause("stload", true, hz, NULL);
629 
630 		periph->periph_flags = oflags;	/* restore flags */
631 		if (slpintr != 0 && slpintr != EWOULDBLOCK) {
632 			goto bad;
633 		}
634 	}
635 
636 
637 	/*
638 	 * If the mode is 3 (e.g. minor = 3,7,11,15) then the device has
639 	 * been opened to set defaults and perform other, usually non-I/O
640 	 * related, operations. In this case, do a quick check to see
641 	 * whether the unit actually had a tape loaded (this will be known
642 	 * as to whether or not we got a NOT READY for the above
643 	 * unit attention). If a tape is there, go do a mount sequence.
644 	 */
645 	if (stmode == CTRL_MODE && st->mt_key == SKEY_NOT_READY) {
646 		periph->periph_flags |= PERIPH_OPEN;
647 		return 0;
648 	}
649 
650 	/*
651 	 * If we get this far and had an error set, that means we failed
652 	 * to pass the 'test unit ready' test for the non-controlmode device,
653 	 * so we bounce the open.
654 	 */
655 	if (error)
656 		return error;
657 
658 	/* Else, we're now committed to saying we're open. */
659 	periph->periph_flags |= PERIPH_OPEN; /* unit attn are now errors */
660 
661 	/*
662 	 * If it's a different mode, or if the media has been
663 	 * invalidated, unmount the tape from the previous
664 	 * session but continue with open processing
665 	 */
666 	if (st->last_dsty != dsty ||
667 	    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
668 		st_unmount(st, NOEJECT);
669 
670 	/*
671 	 * If we are not mounted, then we should start a new
672 	 * mount session.
673 	 */
674 	if (!(st->flags & ST_MOUNTED)) {
675 		if ((error = st_mount_tape(dev, flags)) != 0)
676 			goto bad;
677 		st->last_dsty = dsty;
678 	}
679 	if (!(st->quirks & ST_Q_NOPREVENT)) {
680 		scsipi_prevent(periph, SPAMR_PREVENT_DT,
681 		    XS_CTL_IGNORE_ILLEGAL_REQUEST | XS_CTL_IGNORE_NOT_READY);
682 	}
683 
684 	SC_DEBUG(periph, SCSIPI_DB2, ("open complete\n"));
685 	return 0;
686 
687 bad:
688 	st_unmount(st, NOEJECT);
689 	scsipi_adapter_delref(adapt);
690 	periph->periph_flags &= ~PERIPH_OPEN;
691 	return error;
692 }
693 
694 static int
695 stclose(dev_t dev, int flags, int mode, struct lwp *l)
696 {
697 	int stxx, error = 0;
698 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
699 	struct scsipi_periph *periph = st->sc_periph;
700 	struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;
701 
702 	SC_DEBUG(st->sc_periph, SCSIPI_DB1, ("closing\n"));
703 
704 	/*
705 	 * Make sure that a tape opened in write-only mode will have
706 	 * file marks written on it when closed, even if not written to.
707 	 *
708 	 * This is for SUN compatibility. Actually, the Sun way of
709 	 * things is to:
710 	 *
711 	 *	only write filemarks if there are fmks to be written and
712 	 *   		- open for write (possibly read/write)
713 	 *		- the last operation was a write
714 	 * 	or:
715 	 *		- opened for wronly
716 	 *		- no data was written (including filemarks)
717 	 */
718 
719 	stxx = st->flags & (ST_WRITTEN | ST_FM_WRITTEN);
720 	if (((flags & FWRITE) && stxx == ST_WRITTEN) ||
721 	    ((flags & O_ACCMODE) == FWRITE && stxx == 0)) {
722 		int nm;
723 		error = st_check_eod(st, FALSE, &nm, 0);
724 	}
725 
726 	/* Allow robots to eject tape if needed.  */
727 	scsipi_prevent(periph, SPAMR_ALLOW,
728 	    XS_CTL_IGNORE_ILLEGAL_REQUEST | XS_CTL_IGNORE_NOT_READY);
729 
730 	switch (STMODE(dev)) {
731 	case NORMAL_MODE:
732 		st_unmount(st, NOEJECT);
733 		break;
734 	case NOREW_MODE:
735 	case CTRL_MODE:
736 		/*
737 		 * Leave mounted unless media seems to have been removed.
738 		 *
739 		 * Otherwise, if we're to terminate a tape with more than one
740 		 * filemark [ and because we're not rewinding here ], backspace
741 		 * one filemark so that later appends will see an unbroken
742 		 * sequence of:
743 		 *
744 		 *	file - FMK - file - FMK ... file - FMK FMK (EOM)
745 		 */
746 		if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0) {
747 			st_unmount(st, NOEJECT);
748 		} else if (error == 0) {
749 			/*
750 			 * ST_WRITTEN was preserved from above.
751 			 *
752 			 * All we need to know here is:
753 			 *
754 			 *	Were we writing this tape and was the last
755 			 *	operation a write?
756 			 *
757 			 *	Are there supposed to be 2FM at EOD?
758 			 *
759 			 * If both statements are true, then we backspace
760 			 * one filemark.
761 			 */
762 			stxx |= (st->flags & ST_2FM_AT_EOD);
763 			if ((flags & FWRITE) != 0 &&
764 			    (stxx == (ST_2FM_AT_EOD|ST_WRITTEN))) {
765 				error = st_space(st, -1, SP_FILEMARKS, 0);
766 			}
767 		}
768 		break;
769 	case EJECT_MODE:
770 		st_unmount(st, EJECT);
771 		break;
772 	}
773 
774 	scsipi_wait_drain(periph);
775 
776 	scsipi_adapter_delref(adapt);
777 	periph->periph_flags &= ~PERIPH_OPEN;
778 
779 	return error;
780 }
781 
782 /*
783  * Start a new mount session.
784  * Copy in all the default parameters from the selected device mode.
785  * and try guess any that seem to be defaulted.
786  */
787 static int
788 st_mount_tape(dev_t dev, int flags)
789 {
790 	int unit;
791 	u_int dsty;
792 	struct st_softc *st;
793 	struct scsipi_periph *periph;
794 	int error = 0;
795 
796 	unit = STUNIT(dev);
797 	dsty = STDSTY(dev);
798 	st = device_lookup_private(&st_cd, unit);
799 	periph = st->sc_periph;
800 
801 	if (st->flags & ST_MOUNTED)
802 		return 0;
803 
804 	SC_DEBUG(periph, SCSIPI_DB1, ("mounting\n "));
805 	st->flags |= ST_NEW_MOUNT;
806 	st->quirks = st->drive_quirks | st->modes[dsty].quirks;
807 	/*
808 	 * If the media is new, then make sure we give it a chance to
809 	 * to do a 'load' instruction.  (We assume it is new.)
810 	 */
811 	if ((error = st_load(st, LD_LOAD, XS_CTL_SILENT)) != 0)
812 		return error;
813 	/*
814 	 * Throw another dummy instruction to catch
815 	 * 'Unit attention' errors. Many drives give
816 	 * these after doing a Load instruction (with
817 	 * the MEDIUM MAY HAVE CHANGED asc/ascq).
818 	 */
819 	scsipi_test_unit_ready(periph, XS_CTL_SILENT);	/* XXX */
820 
821 	/*
822 	 * Some devices can't tell you much until they have been
823 	 * asked to look at the media. This quirk does this.
824 	 */
825 	if (st->quirks & ST_Q_SENSE_HELP)
826 		if ((error = st_touch_tape(st)) != 0)
827 			return error;
828 	/*
829 	 * Load the physical device parameters
830 	 * loads: blkmin, blkmax
831 	 */
832 	if ((error = st->ops(st, ST_OPS_RBL, 0)) != 0)
833 		return error;
834 	/*
835 	 * Load the media dependent parameters
836 	 * includes: media_blksize,media_density,numblks
837 	 * As we have a tape in, it should be reflected here.
838 	 * If not you may need the "quirk" above.
839 	 */
840 	if ((error = st->ops(st, ST_OPS_MODESENSE, 0)) != 0)
841 		return error;
842 	/*
843 	 * If we have gained a permanent density from somewhere,
844 	 * then use it in preference to the one supplied by
845 	 * default by the driver.
846 	 */
847 	if (st->modeflags[dsty] & (DENSITY_SET_BY_QUIRK | DENSITY_SET_BY_USER))
848 		st->density = st->modes[dsty].density;
849 	else
850 		st->density = st->media_density;
851 	/*
852 	 * If we have gained a permanent blocksize
853 	 * then use it in preference to the one supplied by
854 	 * default by the driver.
855 	 */
856 	st->flags &= ~ST_FIXEDBLOCKS;
857 	if (st->modeflags[dsty] &
858 	    (BLKSIZE_SET_BY_QUIRK | BLKSIZE_SET_BY_USER)) {
859 		st->blksize = st->modes[dsty].blksize;
860 		if (st->blksize)
861 			st->flags |= ST_FIXEDBLOCKS;
862 	} else {
863 		if ((error = st_decide_mode(st, FALSE)) != 0)
864 			return error;
865 	}
866 	if ((error = st->ops(st, ST_OPS_MODESELECT, 0)) != 0) {
867 		/* ATAPI will return ENODEV for this, and this may be OK */
868 		if (error != ENODEV) {
869 			aprint_error_dev(st->sc_dev,
870 			    "cannot set selected mode\n");
871 			return error;
872 		}
873 	}
874 	st->flags &= ~ST_NEW_MOUNT;
875 	st->flags |= ST_MOUNTED;
876 	periph->periph_flags |= PERIPH_MEDIA_LOADED;	/* move earlier? */
877 	st->blkno = st->fileno = (daddr_t) 0;
878 	return 0;
879 }
880 
881 /*
882  * End the present mount session.
883  * Rewind, and optionally eject the tape.
884  * Reset various flags to indicate that all new
885  * operations require another mount operation
886  */
887 static void
888 st_unmount(struct st_softc *st, boolean eject)
889 {
890 	struct scsipi_periph *periph = st->sc_periph;
891 	int nmarks;
892 
893 	if ((st->flags & ST_MOUNTED) == 0)
894 		return;
895 	SC_DEBUG(periph, SCSIPI_DB1, ("unmounting\n"));
896 	st_check_eod(st, FALSE, &nmarks, XS_CTL_IGNORE_NOT_READY);
897 	st_rewind(st, 0, XS_CTL_IGNORE_NOT_READY);
898 
899 	/*
900 	 * Section 9.3.3 of the SCSI specs states that a device shall return
901 	 * the density value specified in the last succesfull MODE SELECT
902 	 * after an unload operation, in case it is not able to
903 	 * automatically determine the density of the new medium.
904 	 *
905 	 * So we instruct the device to use the default density, which will
906 	 * prevent the use of stale density values (in particular,
907 	 * in st_touch_tape().
908 	 */
909 	st->density = 0;
910 	if (st->ops(st, ST_OPS_MODESELECT, 0) != 0) {
911 		aprint_error_dev(st->sc_dev,
912 		    "WARNING: cannot revert to default density\n");
913 	}
914 
915 	if (eject) {
916 		if (!(st->quirks & ST_Q_NOPREVENT)) {
917 			scsipi_prevent(periph, SPAMR_ALLOW,
918 			    XS_CTL_IGNORE_ILLEGAL_REQUEST |
919 			    XS_CTL_IGNORE_NOT_READY);
920 		}
921 		st_load(st, LD_UNLOAD, XS_CTL_IGNORE_NOT_READY);
922 		st->blkno = st->fileno = (daddr_t) -1;
923 	} else {
924 		st->blkno = st->fileno = (daddr_t) 0;
925 	}
926 	st->flags &= ~(ST_MOUNTED | ST_NEW_MOUNT);
927 	periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
928 }
929 
930 /*
931  * Given all we know about the device, media, mode, 'quirks' and
932  * initial operation, make a decision as to how we should be set
933  * to run (regarding blocking and EOD marks)
934  */
935 int
936 st_decide_mode(struct st_softc *st, boolean first_read)
937 {
938 
939 	SC_DEBUG(st->sc_periph, SCSIPI_DB2, ("starting block mode decision\n"));
940 
941 	/*
942 	 * If the drive can only handle fixed-length blocks and only at
943 	 * one size, perhaps we should just do that.
944 	 */
945 	if (st->blkmin && (st->blkmin == st->blkmax)) {
946 		st->flags |= ST_FIXEDBLOCKS;
947 		st->blksize = st->blkmin;
948 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
949 		    ("blkmin == blkmax of %d\n", st->blkmin));
950 		goto done;
951 	}
952 	/*
953 	 * If the tape density mandates (or even suggests) use of fixed
954 	 * or variable-length blocks, comply.
955 	 */
956 	switch (st->density) {
957 	case HALFINCH_800:
958 	case HALFINCH_1600:
959 	case HALFINCH_6250:
960 	case DDS:
961 		st->flags &= ~ST_FIXEDBLOCKS;
962 		st->blksize = 0;
963 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
964 		    ("density specified variable\n"));
965 		goto done;
966 	case QIC_11:
967 	case QIC_24:
968 	case QIC_120:
969 	case QIC_150:
970 	case QIC_525:
971 	case QIC_1320:
972 	case QIC_3095:
973 	case QIC_3220:
974 		st->flags |= ST_FIXEDBLOCKS;
975 		if (st->media_blksize > 0)
976 			st->blksize = st->media_blksize;
977 		else
978 			st->blksize = DEF_FIXED_BSIZE;
979 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
980 		    ("density specified fixed\n"));
981 		goto done;
982 	}
983 	/*
984 	 * If we're about to read the tape, perhaps we should choose
985 	 * fixed or variable-length blocks and block size according to
986 	 * what the drive found on the tape.
987 	 */
988 	if (first_read &&
989 	    (!(st->quirks & ST_Q_BLKSIZE) || (st->media_blksize == 0) ||
990 	    (st->media_blksize == DEF_FIXED_BSIZE) ||
991 	    (st->media_blksize == 1024))) {
992 		if (st->media_blksize > 0)
993 			st->flags |= ST_FIXEDBLOCKS;
994 		else
995 			st->flags &= ~ST_FIXEDBLOCKS;
996 		st->blksize = st->media_blksize;
997 		SC_DEBUG(st->sc_periph, SCSIPI_DB3,
998 		    ("Used media_blksize of %d\n", st->media_blksize));
999 		goto done;
1000 	}
1001 	/*
1002 	 * We're getting no hints from any direction.  Choose variable-
1003 	 * length blocks arbitrarily.
1004 	 */
1005 	st->flags &= ~ST_FIXEDBLOCKS;
1006 	st->blksize = 0;
1007 	SC_DEBUG(st->sc_periph, SCSIPI_DB3,
1008 	    ("Give up and default to variable mode\n"));
1009 
1010 done:
1011 	/*
1012 	 * Decide whether or not to write two file marks to signify end-
1013 	 * of-data.  Make the decision as a function of density.  If
1014 	 * the decision is not to use a second file mark, the SCSI BLANK
1015 	 * CHECK condition code will be recognized as end-of-data when
1016 	 * first read.
1017 	 * (I think this should be a by-product of fixed/variable..julian)
1018 	 */
1019 	switch (st->density) {
1020 /*      case 8 mm:   What is the SCSI density code for 8 mm, anyway? */
1021 	case QIC_11:
1022 	case QIC_24:
1023 	case QIC_120:
1024 	case QIC_150:
1025 	case QIC_525:
1026 	case QIC_1320:
1027 	case QIC_3095:
1028 	case QIC_3220:
1029 		st->flags &= ~ST_2FM_AT_EOD;
1030 		break;
1031 	default:
1032 		st->flags |= ST_2FM_AT_EOD;
1033 	}
1034 	return 0;
1035 }
1036 
1037 /*
1038  * Actually translate the requested transfer into
1039  * one the physical driver can understand
1040  * The transfer is described by a buf and will include
1041  * only one physical transfer.
1042  */
1043 static void
1044 ststrategy(struct buf *bp)
1045 {
1046 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(bp->b_dev));
1047 	struct scsipi_periph *periph = st->sc_periph;
1048 	struct scsipi_channel *chan = periph->periph_channel;
1049 
1050 	SC_DEBUG(periph, SCSIPI_DB1,
1051 	    ("ststrategy %d bytes @ blk %" PRId64 "\n", bp->b_bcount,
1052 	        bp->b_blkno));
1053 	/* If it's a null transfer, return immediately */
1054 	if (bp->b_bcount == 0)
1055 		goto abort;
1056 
1057 	/* If offset is negative, error */
1058 	if (bp->b_blkno < 0) {
1059 		bp->b_error = EINVAL;
1060 		goto abort;
1061 	}
1062 
1063 	/* Odd sized request on fixed drives are verboten */
1064 	if (st->flags & ST_FIXEDBLOCKS) {
1065 		if (bp->b_bcount % st->blksize) {
1066 			aprint_error_dev(st->sc_dev, "bad request, must be multiple of %d\n",
1067 			    st->blksize);
1068 			bp->b_error = EIO;
1069 			goto abort;
1070 		}
1071 	}
1072 	/* as are out-of-range requests on variable drives. */
1073 	else if (bp->b_bcount < st->blkmin ||
1074 	    (st->blkmax && bp->b_bcount > st->blkmax)) {
1075 		aprint_error_dev(st->sc_dev, "bad request, must be between %d and %d\n",
1076 		    st->blkmin, st->blkmax);
1077 		bp->b_error = EIO;
1078 		goto abort;
1079 	}
1080 	mutex_enter(chan_mtx(chan));
1081 
1082 	/*
1083 	 * Place it in the queue of activities for this tape
1084 	 * at the end (a bit silly because we only have on user..
1085 	 * (but it could fork()))
1086 	 */
1087 	bufq_put(st->buf_queue, bp);
1088 
1089 	/*
1090 	 * Tell the device to get going on the transfer if it's
1091 	 * not doing anything, otherwise just wait for completion
1092 	 * (All a bit silly if we're only allowing 1 open but..)
1093 	 */
1094 	ststart(periph);
1095 
1096 	mutex_exit(chan_mtx(chan));
1097 	return;
1098 abort:
1099 	/*
1100 	 * Reset the residue because we didn't do anything,
1101 	 * and send the buffer back as done.
1102 	 */
1103 	bp->b_resid = bp->b_bcount;
1104 	biodone(bp);
1105 	return;
1106 }
1107 
1108 /*
1109  * ststart looks to see if there is a buf waiting for the device
1110  * and that the device is not already busy. If both are true,
1111  * It dequeues the buf and creates a scsi command to perform the
1112  * transfer required. The transfer request will call scsipi_done
1113  * on completion, which will in turn call this routine again
1114  * so that the next queued transfer is performed.
1115  * The bufs are queued by the strategy routine (ststrategy)
1116  *
1117  * This routine is also called after other non-queued requests
1118  * have been made of the scsi driver, to ensure that the queue
1119  * continues to be drained.
1120  * ststart() is called with channel lock held
1121  */
1122 static void
1123 ststart(struct scsipi_periph *periph)
1124 {
1125 	struct st_softc *st = device_private(periph->periph_dev);
1126 	struct buf *bp;
1127 	struct scsi_rw_tape cmd;
1128 	struct scsipi_xfer *xs;
1129 	int flags, error __diagused;
1130 
1131 	SC_DEBUG(periph, SCSIPI_DB2, ("ststart "));
1132 	/* See if there is a buf to do and we are not already  doing one */
1133 	while (periph->periph_active < periph->periph_openings) {
1134 		/* if a special awaits, let it proceed first */
1135 		if (periph->periph_flags & PERIPH_WAITING) {
1136 			periph->periph_flags &= ~PERIPH_WAITING;
1137 			cv_broadcast(periph_cv_periph(periph));
1138 			return;
1139 		}
1140 
1141 		/*
1142 		 * If the device has been unmounted by the user
1143 		 * then throw away all requests until done.
1144 		 */
1145 		if (__predict_false((st->flags & ST_MOUNTED) == 0 ||
1146 		    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)) {
1147 			if ((bp = bufq_get(st->buf_queue)) != NULL) {
1148 				/* make sure that one implies the other.. */
1149 				periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
1150 				bp->b_error = EIO;
1151 				bp->b_resid = bp->b_bcount;
1152 				biodone(bp);
1153 				continue;
1154 			} else
1155 				return;
1156 		}
1157 
1158 		if ((bp = bufq_peek(st->buf_queue)) == NULL)
1159 			return;
1160 
1161 		iostat_busy(st->stats);
1162 
1163 		/*
1164 		 * only FIXEDBLOCK devices have pending I/O or space operations.
1165 		 */
1166 		if (st->flags & ST_FIXEDBLOCKS) {
1167 			/*
1168 			 * If we are at a filemark but have not reported it yet
1169 			 * then we should report it now
1170 			 */
1171 			if (st->flags & ST_AT_FILEMARK) {
1172 				if ((bp->b_flags & B_READ) == B_WRITE) {
1173 					/*
1174 					 * Handling of ST_AT_FILEMARK in
1175 					 * st_space will fill in the right file
1176 					 * mark count.
1177 					 * Back up over filemark
1178 					 */
1179 					if (st_space(st, 0, SP_FILEMARKS, 0)) {
1180 						bufq_get(st->buf_queue);
1181 						bp->b_error = EIO;
1182 						bp->b_resid = bp->b_bcount;
1183 						biodone(bp);
1184 						continue;
1185 					}
1186 				} else {
1187 					bufq_get(st->buf_queue);
1188 					bp->b_resid = bp->b_bcount;
1189 					bp->b_error = 0;
1190 					st->flags &= ~ST_AT_FILEMARK;
1191 					biodone(bp);
1192 					continue;	/* seek more work */
1193 				}
1194 			}
1195 		}
1196 		/*
1197 		 * If we are at EOM but have not reported it
1198 		 * yet then we should report it now.
1199 		 */
1200 		if (st->flags & (ST_EOM_PENDING|ST_EIO_PENDING)) {
1201 			bufq_get(st->buf_queue);
1202 			bp->b_resid = bp->b_bcount;
1203 			if (st->flags & ST_EIO_PENDING)
1204 				bp->b_error = EIO;
1205 			st->flags &= ~(ST_EOM_PENDING|ST_EIO_PENDING);
1206 			biodone(bp);
1207 			continue;	/* seek more work */
1208 		}
1209 
1210 		/* Fill out the scsi command */
1211 		memset(&cmd, 0, sizeof(cmd));
1212 		flags = XS_CTL_NOSLEEP | XS_CTL_ASYNC;
1213 		if ((bp->b_flags & B_READ) == B_WRITE) {
1214 			cmd.opcode = WRITE;
1215 			st->flags &= ~ST_FM_WRITTEN;
1216 			flags |= XS_CTL_DATA_OUT;
1217 		} else {
1218 			cmd.opcode = READ;
1219 			flags |= XS_CTL_DATA_IN;
1220 		}
1221 
1222 		/*
1223 		 * Handle "fixed-block-mode" tape drives by using the
1224 		 * block count instead of the length.
1225 		 */
1226 		if (st->flags & ST_FIXEDBLOCKS) {
1227 			cmd.byte2 |= SRW_FIXED;
1228 			_lto3b(bp->b_bcount / st->blksize, cmd.len);
1229 		} else
1230 			_lto3b(bp->b_bcount, cmd.len);
1231 
1232 		/* Clear 'position updated' indicator */
1233 		st->flags &= ~ST_POSUPDATED;
1234 
1235 		/* go ask the adapter to do all this for us */
1236 		xs = scsipi_make_xs_locked(periph,
1237 		    (struct scsipi_generic *)&cmd, sizeof(cmd),
1238 		    (u_char *)bp->b_data, bp->b_bcount,
1239 		    0, ST_IO_TIME, bp, flags);
1240 		if (__predict_false(xs == NULL)) {
1241 			/*
1242 			 * out of memory. Keep this buffer in the queue, and
1243 			 * retry later.
1244 			 */
1245 			callout_reset(&st->sc_callout, hz / 2, strestart,
1246 			    periph);
1247 			return;
1248 		}
1249 		/*
1250 		 * need to dequeue the buffer before queuing the command,
1251 		 * because cdstart may be called recursively from the
1252 		 * HBA driver
1253 		 */
1254 #ifdef DIAGNOSTIC
1255 		if (bufq_get(st->buf_queue) != bp)
1256 			panic("ststart(): dequeued wrong buf");
1257 #else
1258 		bufq_get(st->buf_queue);
1259 #endif
1260 		error = scsipi_execute_xs(xs);
1261 		/* with a scsipi_xfer preallocated, scsipi_command can't fail */
1262 		KASSERT(error == 0);
1263 	} /* go back and see if we can cram more work in.. */
1264 }
1265 
1266 static void
1267 strestart(void *v)
1268 {
1269 	struct scsipi_periph *periph = (struct scsipi_periph *)v;
1270 	struct scsipi_channel *chan = periph->periph_channel;
1271 
1272 	mutex_enter(chan_mtx(chan));
1273 	ststart((struct scsipi_periph *)v);
1274 	mutex_exit(chan_mtx(chan));
1275 }
1276 
1277 static void
1278 stdone(struct scsipi_xfer *xs, int error)
1279 {
1280 	struct st_softc *st = device_private(xs->xs_periph->periph_dev);
1281 	struct buf *bp = xs->bp;
1282 
1283 	if (bp) {
1284 		bp->b_error = error;
1285 		bp->b_resid = xs->resid;
1286 		/*
1287 		 * buggy device ? A SDLT320 can report an info
1288 		 * field of 0x3de8000 on a Media Error/Write Error
1289 		 * for this CBD: 0x0a 00 00 80 00 00
1290 		 */
1291 		if (bp->b_resid > bp->b_bcount || bp->b_resid < 0)
1292 			bp->b_resid = bp->b_bcount;
1293 
1294 		if ((bp->b_flags & B_READ) == B_WRITE)
1295 			st->flags |= ST_WRITTEN;
1296 		else
1297 			st->flags &= ~ST_WRITTEN;
1298 
1299 		iostat_unbusy(st->stats, bp->b_bcount,
1300 			     ((bp->b_flags & B_READ) == B_READ));
1301 
1302 		rnd_add_uint32(&st->rnd_source, bp->b_blkno);
1303 
1304 		if ((st->flags & ST_POSUPDATED) == 0) {
1305 			if (error) {
1306 				st->fileno = st->blkno = -1;
1307 			} else if (st->blkno != -1) {
1308 				if (st->flags & ST_FIXEDBLOCKS)
1309 					st->blkno +=
1310 					    (bp->b_bcount / st->blksize);
1311 				else
1312 					st->blkno++;
1313 			}
1314 		}
1315 		biodone(bp);
1316 	}
1317 }
1318 
1319 static int
1320 stread(dev_t dev, struct uio *uio, int iomode)
1321 {
1322 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
1323 
1324 	return physio(ststrategy, NULL, dev, B_READ,
1325 	    st->sc_periph->periph_channel->chan_adapter->adapt_minphys, uio);
1326 }
1327 
1328 static int
1329 stwrite(dev_t dev, struct uio *uio, int iomode)
1330 {
1331 	struct st_softc *st = device_lookup_private(&st_cd, STUNIT(dev));
1332 
1333 	return physio(ststrategy, NULL, dev, B_WRITE,
1334 	    st->sc_periph->periph_channel->chan_adapter->adapt_minphys, uio);
1335 }
1336 
1337 /*
1338  * Perform special action on behalf of the user;
1339  * knows about the internals of this device
1340  */
1341 static int
1342 stioctl(dev_t dev, u_long cmd, void *arg, int flag, struct lwp *l)
1343 {
1344 	int error = 0;
1345 	int unit;
1346 	int number, nmarks, dsty;
1347 	int flags;
1348 	struct st_softc *st;
1349 	int hold_blksize;
1350 	uint8_t hold_density;
1351 	struct mtop *mt = (struct mtop *) arg;
1352 
1353 	/* Find the device that the user is talking about */
1354 	flags = 0;		/* give error messages, act on errors etc. */
1355 	unit = STUNIT(dev);
1356 	dsty = STDSTY(dev);
1357 	st = device_lookup_private(&st_cd, unit);
1358 	hold_blksize = st->blksize;
1359 	hold_density = st->density;
1360 
1361 	switch ((u_int)cmd) {
1362 	case MTIOCGET: {
1363 		struct mtget *g = (struct mtget *) arg;
1364 		/*
1365 		 * (to get the current state of READONLY)
1366 		 */
1367 		error = st->ops(st, ST_OPS_MODESENSE, XS_CTL_SILENT);
1368 		if (error) {
1369 			/*
1370 			 * Ignore the error if in control mode;
1371 			 * this is mandated by st(4).
1372 			 */
1373 			if (STMODE(dev) != CTRL_MODE)
1374 				break;
1375 			error = 0;
1376 		}
1377 		SC_DEBUG(st->sc_periph, SCSIPI_DB1, ("[ioctl: get status]\n"));
1378 		memset(g, 0, sizeof(struct mtget));
1379 		g->mt_type = MT_ISAR;	/* Ultrix compat *//*? */
1380 		g->mt_blksiz = st->blksize;
1381 		g->mt_density = st->density;
1382 		g->mt_mblksiz[0] = st->modes[0].blksize;
1383 		g->mt_mblksiz[1] = st->modes[1].blksize;
1384 		g->mt_mblksiz[2] = st->modes[2].blksize;
1385 		g->mt_mblksiz[3] = st->modes[3].blksize;
1386 		g->mt_mdensity[0] = st->modes[0].density;
1387 		g->mt_mdensity[1] = st->modes[1].density;
1388 		g->mt_mdensity[2] = st->modes[2].density;
1389 		g->mt_mdensity[3] = st->modes[3].density;
1390 		g->mt_fileno = st->fileno;
1391 		g->mt_blkno = st->blkno;
1392 		if (st->flags & ST_READONLY)
1393 			g->mt_dsreg |= MT_DS_RDONLY;
1394 		if (st->flags & ST_MOUNTED)
1395 			g->mt_dsreg |= MT_DS_MOUNTED;
1396 		g->mt_resid = st->mt_resid;
1397 		g->mt_erreg = st->mt_erreg;
1398 		/*
1399 		 * clear latched errors.
1400 		 */
1401 		st->mt_resid = 0;
1402 		st->mt_erreg = 0;
1403 		st->asc = 0;
1404 		st->ascq = 0;
1405 		break;
1406 	}
1407 	case MTIOCTOP: {
1408 		SC_DEBUG(st->sc_periph, SCSIPI_DB1,
1409 		    ("[ioctl: op=0x%x count=0x%x]\n", mt->mt_op,
1410 			mt->mt_count));
1411 
1412 		/* compat: in U*x it is a short */
1413 		number = mt->mt_count;
1414 		switch ((short) (mt->mt_op)) {
1415 		case MTWEOF:	/* write an end-of-file record */
1416 			error = st_write_filemarks(st, number, flags);
1417 			break;
1418 		case MTBSF:	/* backward space file */
1419 			number = -number;
1420 		case MTFSF:	/* forward space file */
1421 			error = st_check_eod(st, FALSE, &nmarks, flags);
1422 			if (!error)
1423 				error = st_space(st, number - nmarks,
1424 				    SP_FILEMARKS, flags);
1425 			break;
1426 		case MTBSR:	/* backward space record */
1427 			number = -number;
1428 		case MTFSR:	/* forward space record */
1429 			error = st_check_eod(st, true, &nmarks, flags);
1430 			if (!error)
1431 				error = st_space(st, number, SP_BLKS, flags);
1432 			break;
1433 		case MTREW:	/* rewind */
1434 			error = st_rewind(st, 0, flags);
1435 			break;
1436 		case MTOFFL:	/* rewind and put the drive offline */
1437 			st_unmount(st, EJECT);
1438 			break;
1439 		case MTNOP:	/* no operation, sets status only */
1440 			break;
1441 		case MTRETEN:	/* retension the tape */
1442 			error = st_load(st, LD_RETENSION, flags);
1443 			if (!error)
1444 				error = st_load(st, LD_LOAD, flags);
1445 			break;
1446 		case MTEOM:	/* forward space to end of media */
1447 			error = st_check_eod(st, FALSE, &nmarks, flags);
1448 			if (!error)
1449 				error = st_space(st, 1, SP_EOM, flags);
1450 			break;
1451 		case MTCACHE:	/* enable controller cache */
1452 			st->flags &= ~ST_DONTBUFFER;
1453 			goto try_new_value;
1454 		case MTNOCACHE:	/* disable controller cache */
1455 			st->flags |= ST_DONTBUFFER;
1456 			goto try_new_value;
1457 		case MTERASE:	/* erase volume */
1458 			error = st_erase(st, number, flags);
1459 			break;
1460 		case MTSETBSIZ:	/* Set block size for device */
1461 #ifdef	NOTYET
1462 			if (!(st->flags & ST_NEW_MOUNT)) {
1463 				uprintf("re-mount tape before changing "
1464 				    "blocksize");
1465 				error = EINVAL;
1466 				break;
1467 			}
1468 #endif
1469 			if (number == 0)
1470 				st->flags &= ~ST_FIXEDBLOCKS;
1471 			else {
1472 				if ((st->blkmin || st->blkmax) &&
1473 				    (number < st->blkmin ||
1474 				    number > st->blkmax)) {
1475 					error = EINVAL;
1476 					break;
1477 				}
1478 				st->flags |= ST_FIXEDBLOCKS;
1479 			}
1480 			st->blksize = number;
1481 			st->flags |= ST_BLOCK_SET;	/*XXX */
1482 			goto try_new_value;
1483 		case MTSETDNSTY:	/* Set density for device and mode */
1484 			/*
1485 			 * Any number >= 0 and <= 0xff is legal. Numbers
1486 			 * above 0x80 are 'vendor unique'.
1487 			 */
1488 			if (number < 0 || number > 255) {
1489 				error = EINVAL;
1490 				break;
1491 			} else
1492 				st->density = number;
1493 			goto try_new_value;
1494 		case MTCMPRESS:
1495 			error = st->ops(st, (number == 0) ?
1496 			    ST_OPS_CMPRSS_OFF : ST_OPS_CMPRSS_ON,
1497 			    XS_CTL_SILENT);
1498 			break;
1499 		case MTEWARN:
1500 			if (number)
1501 				st->flags |= ST_EARLYWARN;
1502 			else
1503 				st->flags &= ~ST_EARLYWARN;
1504 			break;
1505 
1506 		default:
1507 			error = EINVAL;
1508 		}
1509 		break;
1510 	}
1511 	case MTIOCIEOT:
1512 	case MTIOCEEOT:
1513 		break;
1514 	case MTIOCRDSPOS:
1515 		error = st_rdpos(st, 0, (uint32_t *)arg);
1516 		break;
1517 	case MTIOCRDHPOS:
1518 		error = st_rdpos(st, 1, (uint32_t *)arg);
1519 		break;
1520 	case MTIOCSLOCATE:
1521 		error = st_setpos(st, 0, (uint32_t *)arg);
1522 		break;
1523 	case MTIOCHLOCATE:
1524 		error = st_setpos(st, 1, (uint32_t *)arg);
1525 		break;
1526 	default:
1527 		error = scsipi_do_ioctl(st->sc_periph, dev, cmd, arg, flag, l);
1528 		break;
1529 	}
1530 	return error;
1531 
1532 try_new_value:
1533 	/*
1534 	 * Check that the mode being asked for is aggreeable to the
1535 	 * drive. If not, put it back the way it was.
1536 	 *
1537 	 * If in control mode, we can make (persistent) mode changes
1538 	 * even if no medium is loaded (see st(4)).
1539 	 */
1540 	if ((STMODE(dev) != CTRL_MODE || (st->flags & ST_MOUNTED) != 0) &&
1541 	    (error = st->ops(st, ST_OPS_MODESELECT, 0)) != 0) {
1542 		/* put it back as it was */
1543 		aprint_error_dev(st->sc_dev, "cannot set selected mode\n");
1544 		st->density = hold_density;
1545 		st->blksize = hold_blksize;
1546 		if (st->blksize)
1547 			st->flags |= ST_FIXEDBLOCKS;
1548 		else
1549 			st->flags &= ~ST_FIXEDBLOCKS;
1550 		return error;
1551 	}
1552 	/*
1553 	 * As the drive liked it, if we are setting a new default,
1554 	 * set it into the structures as such.
1555 	 *
1556 	 * The means for deciding this are not finalised yet- but
1557 	 * if the device was opened in Control Mode, the values
1558 	 * are persistent now across mounts.
1559 	 */
1560 	if (STMODE(dev) == CTRL_MODE) {
1561 		switch ((short) (mt->mt_op)) {
1562 		case MTSETBSIZ:
1563 			st->modes[dsty].blksize = st->blksize;
1564 			st->modeflags[dsty] |= BLKSIZE_SET_BY_USER;
1565 			break;
1566 		case MTSETDNSTY:
1567 			st->modes[dsty].density = st->density;
1568 			st->modeflags[dsty] |= DENSITY_SET_BY_USER;
1569 			break;
1570 		}
1571 	}
1572 	return 0;
1573 }
1574 
1575 /* Do a synchronous read. */
1576 static int
1577 st_read(struct st_softc *st, char *bf, int size, int flags)
1578 {
1579 	struct scsi_rw_tape cmd;
1580 
1581 	/* If it's a null transfer, return immediatly */
1582 	if (size == 0)
1583 		return 0;
1584 	memset(&cmd, 0, sizeof(cmd));
1585 	cmd.opcode = READ;
1586 	if (st->flags & ST_FIXEDBLOCKS) {
1587 		cmd.byte2 |= SRW_FIXED;
1588 		_lto3b(size / (st->blksize ? st->blksize : DEF_FIXED_BSIZE),
1589 		    cmd.len);
1590 	} else
1591 		_lto3b(size, cmd.len);
1592 	return scsipi_command(st->sc_periph,
1593 	    (void *)&cmd, sizeof(cmd), (void *)bf, size, 0, ST_IO_TIME, NULL,
1594 	    flags | XS_CTL_DATA_IN);
1595 }
1596 
1597 /* issue an erase command */
1598 static int
1599 st_erase(struct st_softc *st, int full, int flags)
1600 {
1601 	int tmo;
1602 	struct scsi_erase cmd;
1603 
1604 	/*
1605 	 * Full erase means set LONG bit in erase command, which asks
1606 	 * the drive to erase the entire unit.  Without this bit, we're
1607 	 * asking the drive to write an erase gap.
1608 	 */
1609 	memset(&cmd, 0, sizeof(cmd));
1610 	cmd.opcode = ERASE;
1611 	if (full) {
1612 		cmd.byte2 = SE_LONG;
1613 		tmo = ST_SPC_TIME;
1614 	} else
1615 		tmo = ST_IO_TIME;
1616 
1617 	/*
1618 	 * XXX We always do this asynchronously, for now, unless the device
1619 	 * has the ST_Q_ERASE_NOIMM quirk.  How long should we wait if we
1620 	 * want to (eventually) to it synchronously?
1621 	 */
1622 	if ((st->quirks & ST_Q_ERASE_NOIMM) == 0)
1623 		cmd.byte2 |= SE_IMMED;
1624 
1625 	return scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1626 	    ST_RETRIES, tmo, NULL, flags);
1627 }
1628 
1629 /* skip N blocks/filemarks/seq filemarks/eom */
1630 static int
1631 st_space(struct st_softc *st, int number, u_int what, int flags)
1632 {
1633 	struct scsi_space cmd;
1634 	int error;
1635 
1636 	switch (what) {
1637 	case SP_BLKS:
1638 		if (st->flags & ST_PER_ACTION) {
1639 			if (number > 0) {
1640 				st->flags &= ~ST_PER_ACTION;
1641 				return EIO;
1642 			} else if (number < 0) {
1643 				if (st->flags & ST_AT_FILEMARK) {
1644 					/*
1645 					 * Handling of ST_AT_FILEMARK
1646 					 * in st_space will fill in the
1647 					 * right file mark count.
1648 					 */
1649 					error = st_space(st, 0, SP_FILEMARKS,
1650 					    flags);
1651 					if (error)
1652 						return error;
1653 				}
1654 				if (st->flags & ST_BLANK_READ) {
1655 					st->flags &= ~ST_BLANK_READ;
1656 					return EIO;
1657 				}
1658 				st->flags &= ~(ST_EIO_PENDING|ST_EOM_PENDING);
1659 			}
1660 		}
1661 		break;
1662 	case SP_FILEMARKS:
1663 		if (st->flags & ST_EIO_PENDING) {
1664 			if (number > 0) {
1665 				/* pretend we just discovered the error */
1666 				st->flags &= ~ST_EIO_PENDING;
1667 				return EIO;
1668 			} else if (number < 0) {
1669 				/* back away from the error */
1670 				st->flags &= ~ST_EIO_PENDING;
1671 			}
1672 		}
1673 		if (st->flags & ST_AT_FILEMARK) {
1674 			st->flags &= ~ST_AT_FILEMARK;
1675 			number--;
1676 		}
1677 		if ((st->flags & ST_BLANK_READ) && (number < 0)) {
1678 			/* back away from unwritten tape */
1679 			st->flags &= ~ST_BLANK_READ;
1680 			number++;	/* XXX dubious */
1681 		}
1682 		break;
1683 	case SP_EOM:
1684 		if (st->flags & ST_EOM_PENDING) {
1685 			/* we're already there */
1686 			st->flags &= ~ST_EOM_PENDING;
1687 			return 0;
1688 		}
1689 		if (st->flags & ST_EIO_PENDING) {
1690 			/* pretend we just discovered the error */
1691 			st->flags &= ~ST_EIO_PENDING;
1692 			return EIO;
1693 		}
1694 		if (st->flags & ST_AT_FILEMARK)
1695 			st->flags &= ~ST_AT_FILEMARK;
1696 		break;
1697 	}
1698 	if (number == 0)
1699 		return 0;
1700 
1701 	memset(&cmd, 0, sizeof(cmd));
1702 	cmd.opcode = SPACE;
1703 	cmd.byte2 = what;
1704 	_lto3b(number, cmd.number);
1705 
1706 	st->flags &= ~ST_POSUPDATED;
1707 	st->last_ctl_resid = 0;
1708 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1709 	    0, ST_SPC_TIME, NULL, flags);
1710 
1711 	if (error == 0 && (st->flags & ST_POSUPDATED) == 0) {
1712 		number = number - st->last_ctl_resid;
1713 		if (what == SP_BLKS) {
1714 			if (st->blkno != -1)
1715 				st->blkno += number;
1716 		} else if (what == SP_FILEMARKS) {
1717 			if (st->fileno != -1) {
1718 				st->fileno += number;
1719 				if (number > 0)
1720 					st->blkno = 0;
1721 				else if (number < 0)
1722 					st->blkno = -1;
1723 			}
1724 		} else if (what == SP_EOM) {
1725 			/* This loses us relative position. */
1726 			st->fileno = st->blkno = -1;
1727 		}
1728 	}
1729 	return error;
1730 }
1731 
1732 /*
1733  * write N filemarks
1734  */
1735 static int
1736 st_write_filemarks(struct st_softc *st, int number, int flags)
1737 {
1738 	int error;
1739 	struct scsi_write_filemarks cmd;
1740 
1741 	/*
1742 	 * It's hard to write a negative number of file marks.
1743 	 * Don't try.
1744 	 */
1745 	if (number < 0)
1746 		return EINVAL;
1747 	switch (number) {
1748 	case 0:		/* really a command to sync the drive's buffers */
1749 		break;
1750 	case 1:
1751 		if (st->flags & ST_FM_WRITTEN)	/* already have one down */
1752 			st->flags &= ~ST_WRITTEN;
1753 		else
1754 			st->flags |= ST_FM_WRITTEN;
1755 		st->flags &= ~ST_PER_ACTION;
1756 		break;
1757 	default:
1758 		st->flags &= ~(ST_PER_ACTION | ST_WRITTEN);
1759 	}
1760 
1761 	memset(&cmd, 0, sizeof(cmd));
1762 	cmd.opcode = WRITE_FILEMARKS;
1763 	if (SCSIPI_BUSTYPE_TYPE(scsipi_periph_bustype(st->sc_periph)) ==
1764 	    SCSIPI_BUSTYPE_ATAPI)
1765 		cmd.byte2 = SR_IMMED;
1766 	/*
1767 	 * The ATAPI Onstream DI-30 doesn't support writing filemarks, but
1768 	 * WRITE_FILEMARKS is still used to flush the buffer
1769 	 */
1770 	if ((st->quirks & ST_Q_NOFILEMARKS) == 0)
1771 		_lto3b(number, cmd.number);
1772 
1773 	/* XXX WE NEED TO BE ABLE TO GET A RESIDIUAL XXX */
1774 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1775 	    0, ST_IO_TIME * 4, NULL, flags);
1776 	if (error == 0 && st->fileno != -1)
1777 		st->fileno += number;
1778 	return error;
1779 }
1780 
1781 /*
1782  * Make sure the right number of file marks is on tape if the
1783  * tape has been written.  If the position argument is true,
1784  * leave the tape positioned where it was originally.
1785  *
1786  * nmarks returns the number of marks to skip (or, if position
1787  * true, which were skipped) to get back original position.
1788  */
1789 static int
1790 st_check_eod(struct st_softc *st, boolean position, int *nmarks, int flags)
1791 {
1792 	int error;
1793 
1794 	switch (st->flags & (ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD)) {
1795 	default:
1796 		*nmarks = 0;
1797 		return 0;
1798 	case ST_WRITTEN:
1799 	case ST_WRITTEN | ST_FM_WRITTEN | ST_2FM_AT_EOD:
1800 		*nmarks = 1;
1801 		break;
1802 	case ST_WRITTEN | ST_2FM_AT_EOD:
1803 		*nmarks = 2;
1804 	}
1805 	error = st_write_filemarks(st, *nmarks, flags);
1806 	if (position && !error)
1807 		error = st_space(st, -*nmarks, SP_FILEMARKS, flags);
1808 	return error;
1809 }
1810 
1811 /* load/unload/retension */
1812 static int
1813 st_load(struct st_softc *st, u_int type, int flags)
1814 {
1815 	int error;
1816 	struct scsi_load cmd;
1817 
1818 	if (type != LD_LOAD) {
1819 		int nmarks;
1820 
1821 		error = st_check_eod(st, FALSE, &nmarks, flags);
1822 		if (error) {
1823 			aprint_error_dev(st->sc_dev,
1824 			    "failed to write closing filemarks at "
1825 			    "unload, errno=%d\n", error);
1826 			return error;
1827 		}
1828 	}
1829 	if (st->quirks & ST_Q_IGNORE_LOADS) {
1830 		if (type == LD_LOAD)
1831 			/*
1832 			 * If we ignore loads, at least we should try a rewind.
1833 			 */
1834 			return st_rewind(st, 0, flags);
1835 		/* otherwise, we should do what's asked of us */
1836 	}
1837 
1838 	memset(&cmd, 0, sizeof(cmd));
1839 	cmd.opcode = LOAD;
1840 	if (SCSIPI_BUSTYPE_TYPE(scsipi_periph_bustype(st->sc_periph)) ==
1841 	    SCSIPI_BUSTYPE_ATAPI)
1842 		cmd.byte2 = SR_IMMED;
1843 	cmd.how = type;
1844 
1845 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1846 	    ST_RETRIES, ST_SPC_TIME, NULL, flags);
1847 	if (error) {
1848 		aprint_error_dev(st->sc_dev, "error %d in st_load (op %d)\n",
1849 		    error, type);
1850 	}
1851 	return error;
1852 }
1853 
1854 /* Rewind the device */
1855 static int
1856 st_rewind(struct st_softc *st, u_int immediate, int flags)
1857 {
1858 	struct scsi_rewind cmd;
1859 	int error;
1860 	int nmarks;
1861 	int timeout;
1862 
1863 	error = st_check_eod(st, FALSE, &nmarks, flags);
1864 	if (error) {
1865 		aprint_error_dev(st->sc_dev,
1866 		    "failed to write closing filemarks at "
1867 		    "rewind, errno=%d\n", error);
1868 		return error;
1869 	}
1870 	st->flags &= ~ST_PER_ACTION;
1871 
1872 	/* If requestor asked for immediate response, set a short timeout */
1873 	timeout = immediate ? ST_CTL_TIME : ST_SPC_TIME;
1874 
1875 	/* ATAPI tapes always need immediate to be set */
1876 	if (scsipi_periph_bustype(st->sc_periph) == SCSIPI_BUSTYPE_ATAPI)
1877 		immediate = SR_IMMED;
1878 
1879 	memset(&cmd, 0, sizeof(cmd));
1880 	cmd.opcode = REWIND;
1881 	cmd.byte2 = immediate;
1882 
1883 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1884 	    ST_RETRIES, timeout, NULL, flags);
1885 	if (error) {
1886 		aprint_error_dev(st->sc_dev, "error %d trying to rewind\n",
1887 		    error);
1888 		/* lost position */
1889 		st->fileno = st->blkno = -1;
1890 	} else
1891 		st->fileno = st->blkno = 0;
1892 	return error;
1893 }
1894 
1895 static int
1896 st_rdpos(struct st_softc *st, int hard, uint32_t *blkptr)
1897 {
1898 	int error;
1899 	uint8_t posdata[20];
1900 	struct scsi_tape_read_position cmd;
1901 
1902 	/*
1903 	 * We try and flush any buffered writes here if we were writing
1904 	 * and we're trying to get hardware block position. It eats
1905 	 * up performance substantially, but I'm wary of drive firmware.
1906 	 *
1907 	 * I think that *logical* block position is probably okay-
1908 	 * but hardware block position might have to wait for data
1909 	 * to hit media to be valid. Caveat Emptor.
1910 	 */
1911 
1912 	if (hard && (st->flags & ST_WRITTEN)) {
1913 		/* First flush any pending writes... */
1914 		error = st_write_filemarks(st, 0, XS_CTL_SILENT);
1915 		/*
1916 		 * The latter case is for 'write protected' tapes
1917 		 * which are too stupid to recognize a zero count
1918 		 * for writing filemarks as a no-op.
1919 		 */
1920 		if (error != 0 && error != EACCES && error != EROFS)
1921 			return error;
1922 	}
1923 
1924 	memset(&cmd, 0, sizeof(cmd));
1925 	memset(&posdata, 0, sizeof(posdata));
1926 	cmd.opcode = READ_POSITION;
1927 	if (hard)
1928 		cmd.byte1 = 1;
1929 
1930 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd),
1931 	    (void *)&posdata, sizeof(posdata), ST_RETRIES, ST_CTL_TIME, NULL,
1932 	    XS_CTL_SILENT | XS_CTL_DATA_IN);
1933 
1934 	if (error == 0) {
1935 #if	0
1936 		printf("posdata:");
1937 		for (hard = 0; hard < sizeof(posdata); hard++)
1938 			printf("%02x ", posdata[hard] & 0xff);
1939 		printf("\n");
1940 #endif
1941 		if (posdata[0] & 0x4)	/* Block Position Unknown */
1942 			error = EINVAL;
1943 		else
1944 			*blkptr = _4btol(&posdata[4]);
1945 	}
1946 	return error;
1947 }
1948 
1949 static int
1950 st_setpos(struct st_softc *st, int hard, uint32_t *blkptr)
1951 {
1952 	int error;
1953 	struct scsi_tape_locate cmd;
1954 
1955 	/*
1956 	 * We used to try and flush any buffered writes here.
1957 	 * Now we push this onto user applications to either
1958 	 * flush the pending writes themselves (via a zero count
1959 	 * WRITE FILEMARKS command) or they can trust their tape
1960 	 * drive to do this correctly for them.
1961 	 *
1962 	 * There are very ugly performance limitations otherwise.
1963 	 */
1964 
1965 	memset(&cmd, 0, sizeof(cmd));
1966 	cmd.opcode = LOCATE;
1967 	if (hard)
1968 		cmd.byte2 = 1 << 2;
1969 	_lto4b(*blkptr, cmd.blkaddr);
1970 	error = scsipi_command(st->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1971 	    ST_RETRIES, ST_SPC_TIME, NULL, 0);
1972 	/*
1973 	 * Note file && block number position now unknown (if
1974 	 * these things ever start being maintained in this driver)
1975 	 */
1976 	st->fileno = st->blkno = -1;
1977 	return error;
1978 }
1979 
1980 
1981 /*
1982  * Look at the returned sense and act on the error and determine
1983  * the unix error number to pass back..., 0 (== report no error),
1984  * -1 = retry the operation, -2 continue error processing.
1985  */
1986 static int
1987 st_interpret_sense(struct scsipi_xfer *xs)
1988 {
1989 	struct scsipi_periph *periph = xs->xs_periph;
1990 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
1991 	struct buf *bp = xs->bp;
1992 	struct st_softc *st = device_private(periph->periph_dev);
1993 	int retval = EJUSTRETURN;
1994 	int doprint = ((xs->xs_control & XS_CTL_SILENT) == 0);
1995 	uint8_t key;
1996 	int32_t info;
1997 
1998 	/*
1999 	 * If it isn't a extended or extended/deferred error, let
2000 	 * the generic code handle it.
2001 	 */
2002 	if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
2003 	    SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
2004 		return retval;
2005 
2006 	if (sense->response_code & SSD_RCODE_VALID)
2007 		info = _4btol(sense->info);
2008 	else
2009 		info = (st->flags & ST_FIXEDBLOCKS) ?
2010 		    xs->datalen / st->blksize : xs->datalen;
2011 	key = SSD_SENSE_KEY(sense->flags);
2012 	st->mt_erreg = key;
2013 	st->asc = sense->asc;
2014 	st->ascq = sense->ascq;
2015 	st->mt_resid = (short) info;
2016 
2017 	if (key == SKEY_NOT_READY && st->asc == 0x4 && st->ascq == 0x1) {
2018 		/* Not Ready, Logical Unit Is in Process Of Becoming Ready */
2019 		if (!callout_pending(&periph->periph_callout))
2020 			scsipi_periph_freeze(periph, 1);
2021 		callout_reset(&periph->periph_callout,
2022 		    hz, scsipi_periph_timed_thaw, periph);
2023 		return ERESTART;
2024 	}
2025 
2026 	/* If the device is not open yet, let generic handle */
2027 	if ((periph->periph_flags & PERIPH_OPEN) == 0)
2028 		return retval;
2029 
2030 	xs->resid = info;
2031 	if (st->flags & ST_FIXEDBLOCKS) {
2032 		if (bp) {
2033 			xs->resid *= st->blksize;
2034 			st->last_io_resid = xs->resid;
2035 		} else
2036 			st->last_ctl_resid = xs->resid;
2037 		if (key == SKEY_VOLUME_OVERFLOW) {
2038 			st->flags |= ST_EIO_PENDING;
2039 			if (bp)
2040 				bp->b_resid = xs->resid;
2041 		} else if (sense->flags & SSD_EOM) {
2042 			if ((st->flags & ST_EARLYWARN) == 0)
2043 				st->flags |= ST_EIO_PENDING;
2044 			st->flags |= ST_EOM_PENDING;
2045 			if (bp) {
2046 #if 0
2047 				bp->b_resid = xs->resid;
2048 #else
2049 				/*
2050 				 * Grotesque as it seems, the few times
2051 				 * I've actually seen a non-zero resid,
2052 				 * the tape drive actually lied and had
2053 				 * written all the data!
2054 				 */
2055 				bp->b_resid = 0;
2056 #endif
2057 			}
2058 		}
2059 		if (sense->flags & SSD_FILEMARK) {
2060 			st->flags |= ST_AT_FILEMARK;
2061 			if (bp)
2062 				bp->b_resid = xs->resid;
2063 			if (st->fileno != (daddr_t) -1) {
2064 				st->fileno++;
2065 				st->blkno = 0;
2066 				st->flags |= ST_POSUPDATED;
2067 			}
2068 		}
2069 		if (sense->flags & SSD_ILI) {
2070 			st->flags |= ST_EIO_PENDING;
2071 			if (bp)
2072 				bp->b_resid = xs->resid;
2073 			if (sense->response_code & SSD_RCODE_VALID &&
2074 			    (xs->xs_control & XS_CTL_SILENT) == 0)
2075 				aprint_error_dev(st->sc_dev,
2076 				    "block wrong size, %d blocks residual\n",
2077 				    info);
2078 
2079 			/*
2080 			 * This quirk code helps the drive read
2081 			 * the first tape block, regardless of
2082 			 * format.  That is required for these
2083 			 * drives to return proper MODE SENSE
2084 			 * information.
2085 			 */
2086 			if ((st->quirks & ST_Q_SENSE_HELP) &&
2087 			    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
2088 				st->blksize -= 512;
2089 			else if ((st->flags & ST_POSUPDATED) == 0) {
2090 				if (st->blkno != (daddr_t) -1) {
2091 					st->blkno +=
2092 					    (xs->datalen / st->blksize);
2093 					st->flags |= ST_POSUPDATED;
2094 				}
2095 			}
2096 		}
2097 		/*
2098 		 * If data wanted and no data was transferred, do it immediately
2099 		 */
2100 		if (xs->datalen && xs->resid >= xs->datalen) {
2101 			if (st->flags & ST_EIO_PENDING)
2102 				return EIO;
2103 			if (st->flags & ST_AT_FILEMARK) {
2104 				if (bp)
2105 					bp->b_resid = xs->resid;
2106 				return 0;
2107 			}
2108 		}
2109 	} else {		/* must be variable mode */
2110 		if (bp)
2111 			st->last_io_resid = xs->resid;
2112 		else
2113 			st->last_ctl_resid = xs->resid;
2114 		if (sense->flags & SSD_EOM) {
2115 			/*
2116 			 * The current semantics of this
2117 			 * driver requires EOM detection
2118 			 * to return EIO unless early
2119 			 * warning detection is enabled
2120 			 * for variable mode (this is always
2121 			 * on for fixed block mode).
2122 			 */
2123 			if (st->flags & ST_EARLYWARN) {
2124 				st->flags |= ST_EOM_PENDING;
2125 				retval = 0;
2126 			} else {
2127 				retval = EIO;
2128 				/*
2129 				 * If we return an error we can't claim to
2130 				 * have transfered all data.
2131 				 */
2132 				if (xs->resid == 0)
2133 					xs->resid = xs->datalen;
2134 			}
2135 
2136 			/*
2137 			 * If it's an unadorned EOM detection,
2138 			 * suppress printing an error.
2139 			 */
2140 			if (key == SKEY_NO_SENSE) {
2141 				doprint = 0;
2142 			}
2143 		} else if (sense->flags & SSD_FILEMARK) {
2144 			retval = 0;
2145 			if (st->fileno != (daddr_t) -1) {
2146 				st->fileno++;
2147 				st->blkno = 0;
2148 				st->flags |= ST_POSUPDATED;
2149 			}
2150 		} else if (sense->flags & SSD_ILI) {
2151 			if (info < 0) {
2152 				/*
2153 				 * The tape record was bigger than the read
2154 				 * we issued.
2155 				 */
2156 				if ((xs->xs_control & XS_CTL_SILENT) == 0) {
2157 					aprint_error_dev(st->sc_dev,
2158 					    "%d-byte tape record too big"
2159 					    " for %d-byte user buffer\n",
2160 					    xs->datalen - info, xs->datalen);
2161 				}
2162 				retval = EIO;
2163 			} else {
2164 				retval = 0;
2165 				if (st->blkno != (daddr_t) -1) {
2166 					st->blkno++;
2167 					st->flags |= ST_POSUPDATED;
2168 				}
2169 			}
2170 		}
2171 		if (bp)
2172 			bp->b_resid = xs->resid;
2173 	}
2174 
2175 #ifndef SCSIPI_DEBUG
2176 	if (retval == 0 && key == SKEY_NO_SENSE)
2177 		doprint = 0;
2178 #endif
2179 	if (key == SKEY_BLANK_CHECK) {
2180 		/*
2181 		 * This quirk code helps the drive read the
2182 		 * first tape block, regardless of format.  That
2183 		 * is required for these drives to return proper
2184 		 * MODE SENSE information.
2185 		 */
2186 		if ((st->quirks & ST_Q_SENSE_HELP) &&
2187 		    (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0) {
2188 			/* still starting */
2189 			st->blksize -= 512;
2190 		} else if (!(st->flags & (ST_2FM_AT_EOD | ST_BLANK_READ))) {
2191 			st->flags |= ST_BLANK_READ;
2192 			xs->resid = xs->datalen;
2193 			if (bp) {
2194 				bp->b_resid = xs->resid;
2195 				/* return an EOF */
2196 			}
2197 			retval = 0;
2198 			/* lost position */
2199 			st->fileno = st->blkno = -1;
2200 		}
2201 	}
2202 
2203 	/*
2204 	 * If generic sense processing will continue, we should not
2205 	 * print sense info here.
2206 	 */
2207 	if (retval == EJUSTRETURN)
2208 		doprint = 0;
2209 
2210 	if (doprint) {
2211 		/* Print verbose sense info if possible */
2212 		if (scsipi_print_sense(xs, 0) != 0)
2213 			return retval;
2214 
2215 		/* Print less-verbose sense info */
2216 		scsipi_printaddr(periph);
2217 		printf("Sense Key 0x%02x", key);
2218 		if ((sense->response_code & SSD_RCODE_VALID) != 0) {
2219 			switch (key) {
2220 			case SKEY_NOT_READY:
2221 			case SKEY_ILLEGAL_REQUEST:
2222 			case SKEY_UNIT_ATTENTION:
2223 			case SKEY_DATA_PROTECT:
2224 				break;
2225 			case SKEY_VOLUME_OVERFLOW:
2226 			case SKEY_BLANK_CHECK:
2227 				printf(", requested size: %d (decimal)", info);
2228 				break;
2229 			case SKEY_ABORTED_COMMAND:
2230 				if (xs->xs_retries)
2231 					printf(", retrying");
2232 				printf(", cmd 0x%x, info 0x%x",
2233 				    xs->cmd->opcode, info);
2234 				break;
2235 			default:
2236 				printf(", info = %d (decimal)", info);
2237 			}
2238 		}
2239 		if (sense->extra_len != 0) {
2240 			int n;
2241 			printf(", data =");
2242 			for (n = 0; n < sense->extra_len; n++)
2243 				printf(" %02x", sense->csi[n]);
2244 		}
2245 		printf("\n");
2246 	}
2247 	return retval;
2248 }
2249 
2250 /*
2251  * The quirk here is that the drive returns some value to st_mode_sense
2252  * incorrectly until the tape has actually passed by the head.
2253  *
2254  * The method is to set the drive to large fixed-block state (user-specified
2255  * density and 1024-byte blocks), then read and rewind to get it to sense the
2256  * tape.  If that doesn't work, try 512-byte fixed blocks.  If that doesn't
2257  * work, as a last resort, try variable- length blocks.  The result will be
2258  * the ability to do an accurate st_mode_sense.
2259  *
2260  * We know we can do a rewind because we just did a load, which implies rewind.
2261  * Rewind seems preferable to space backward if we have a virgin tape.
2262  *
2263  * The rest of the code for this quirk is in ILI processing and BLANK CHECK
2264  * error processing, both part of st_interpret_sense.
2265  */
2266 static int
2267 st_touch_tape(struct st_softc *st)
2268 {
2269 	char *bf;
2270 	int readsize;
2271 	int error;
2272 
2273 	bf = malloc(1024, M_TEMP, M_NOWAIT);
2274 	if (bf == NULL)
2275 		return ENOMEM;
2276 
2277 	if ((error = st->ops(st, ST_OPS_MODESENSE, 0)) != 0)
2278 		goto bad;
2279 
2280 	/*
2281 	 * If the block size is already known from the
2282 	 * sense data, use it. Else start probing at 1024.
2283 	 */
2284 	if (st->media_blksize > 0)
2285 		st->blksize = st->media_blksize;
2286 	else
2287 		st->blksize = 1024;
2288 
2289 	do {
2290 		switch (st->blksize) {
2291 		case 512:
2292 		case 1024:
2293 			readsize = st->blksize;
2294 			st->flags |= ST_FIXEDBLOCKS;
2295 			break;
2296 		default:
2297 			readsize = 1;
2298 			st->flags &= ~ST_FIXEDBLOCKS;
2299 		}
2300 		if ((error = st->ops(st, ST_OPS_MODESELECT, XS_CTL_SILENT))
2301 		    != 0) {
2302 			/*
2303 			 * The device did not agree with the proposed
2304 			 * block size. If we exhausted our options,
2305 			 * return failure, else try another.
2306 			 */
2307 			if (readsize == 1)
2308 				goto bad;
2309 			st->blksize -= 512;
2310 			continue;
2311 		}
2312 		st_read(st, bf, readsize, XS_CTL_SILENT);	/* XXX */
2313 		if ((error = st_rewind(st, 0, 0)) != 0) {
2314 bad:			free(bf, M_TEMP);
2315 			return error;
2316 		}
2317 	} while (readsize != 1 && readsize > st->blksize);
2318 
2319 	free(bf, M_TEMP);
2320 	return 0;
2321 }
2322 
2323 static int
2324 stdump(dev_t dev, daddr_t blkno, void *va, size_t size)
2325 {
2326 	/* Not implemented. */
2327 	return ENXIO;
2328 }
2329 
2330 /*
2331  * Send a filled out parameter structure to the drive to
2332  * set it into the desire modes etc.
2333  */
2334 int
2335 st_mode_select(struct st_softc *st, int flags)
2336 {
2337 	u_int select_len;
2338 	struct select {
2339 		struct scsi_mode_parameter_header_6 header;
2340 		struct scsi_general_block_descriptor blk_desc;
2341 		u_char sense_data[MAX_PAGE_0_SIZE];
2342 	} select;
2343 	struct scsipi_periph *periph = st->sc_periph;
2344 
2345 	select_len = sizeof(select.header) + sizeof(select.blk_desc) +
2346 		     st->page_0_size;
2347 
2348 	/*
2349 	 * This quirk deals with drives that have only one valid mode
2350 	 * and think this gives them license to reject all mode selects,
2351 	 * even if the selected mode is the one that is supported.
2352 	 */
2353 	if (st->quirks & ST_Q_UNIMODAL) {
2354 		SC_DEBUG(periph, SCSIPI_DB3,
2355 		    ("not setting density 0x%x blksize 0x%x\n",
2356 		    st->density, st->blksize));
2357 		return 0;
2358 	}
2359 
2360 	/* Set up for a mode select */
2361 	memset(&select, 0, sizeof(select));
2362 	select.header.blk_desc_len = sizeof(struct
2363 	    scsi_general_block_descriptor);
2364 	select.header.dev_spec &= ~SMH_DSP_BUFF_MODE;
2365 	select.blk_desc.density = st->density;
2366 	if (st->flags & ST_DONTBUFFER)
2367 		select.header.dev_spec |= SMH_DSP_BUFF_MODE_OFF;
2368 	else
2369 		select.header.dev_spec |= SMH_DSP_BUFF_MODE_ON;
2370 	if (st->flags & ST_FIXEDBLOCKS)
2371 		_lto3b(st->blksize, select.blk_desc.blklen);
2372 	if (st->page_0_size)
2373 		memcpy(select.sense_data, st->sense_data, st->page_0_size);
2374 
2375 	/* do the command */
2376 	return scsipi_mode_select(periph, 0, &select.header, select_len,
2377 				  flags, ST_RETRIES, ST_CTL_TIME);
2378 }
2379