xref: /freebsd/sys/cam/cam_periph.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*
2  * Common functions for CAM "type" (peripheral) drivers.
3  *
4  * Copyright (c) 1997, 1998 Justin T. Gibbs.
5  * Copyright (c) 1997, 1998, 1999, 2000 Kenneth D. Merry.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions, and the following disclaimer,
13  *    without modification, immediately at the beginning of the file.
14  * 2. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/types.h>
36 #include <sys/malloc.h>
37 #include <sys/linker_set.h>
38 #include <sys/bio.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/buf.h>
42 #include <sys/proc.h>
43 #include <sys/devicestat.h>
44 #include <sys/bus.h>
45 #include <vm/vm.h>
46 #include <vm/vm_extern.h>
47 
48 #include <cam/cam.h>
49 #include <cam/cam_ccb.h>
50 #include <cam/cam_xpt_periph.h>
51 #include <cam/cam_periph.h>
52 #include <cam/cam_debug.h>
53 
54 #include <cam/scsi/scsi_all.h>
55 #include <cam/scsi/scsi_message.h>
56 #include <cam/scsi/scsi_pass.h>
57 
58 static	u_int		camperiphnextunit(struct periph_driver *p_drv,
59 					  u_int newunit, int wired,
60 					  path_id_t pathid, target_id_t target,
61 					  lun_id_t lun);
62 static	u_int		camperiphunit(struct periph_driver *p_drv,
63 				      path_id_t pathid, target_id_t target,
64 				      lun_id_t lun);
65 static	void		camperiphdone(struct cam_periph *periph,
66 					union ccb *done_ccb);
67 static  void		camperiphfree(struct cam_periph *periph);
68 static int		camperiphscsistatuserror(union ccb *ccb,
69 						 cam_flags camflags,
70 						 u_int32_t sense_flags,
71 						 union ccb *save_ccb,
72 						 int *openings,
73 						 u_int32_t *relsim_flags,
74 						 u_int32_t *timeout);
75 static	int		camperiphscsisenseerror(union ccb *ccb,
76 					        cam_flags camflags,
77 					        u_int32_t sense_flags,
78 					        union ccb *save_ccb,
79 					        int *openings,
80 					        u_int32_t *relsim_flags,
81 					        u_int32_t *timeout);
82 
83 static int nperiph_drivers;
84 struct periph_driver **periph_drivers;
85 
86 void
87 periphdriver_register(void *data)
88 {
89 	struct periph_driver **newdrivers, **old;
90 	int ndrivers;
91 
92 	ndrivers = nperiph_drivers + 2;
93 	newdrivers = malloc(sizeof(*newdrivers) * ndrivers, M_TEMP, M_WAITOK);
94 	if (periph_drivers)
95 		bcopy(periph_drivers, newdrivers,
96 		      sizeof(*newdrivers) * nperiph_drivers);
97 	newdrivers[nperiph_drivers] = (struct periph_driver *)data;
98 	newdrivers[nperiph_drivers + 1] = NULL;
99 	old = periph_drivers;
100 	periph_drivers = newdrivers;
101 	if (old)
102 		free(old, M_TEMP);
103 	nperiph_drivers++;
104 }
105 
106 cam_status
107 cam_periph_alloc(periph_ctor_t *periph_ctor,
108 		 periph_oninv_t *periph_oninvalidate,
109 		 periph_dtor_t *periph_dtor, periph_start_t *periph_start,
110 		 char *name, cam_periph_type type, struct cam_path *path,
111 		 ac_callback_t *ac_callback, ac_code code, void *arg)
112 {
113 	struct		periph_driver **p_drv;
114 	struct		cam_periph *periph;
115 	struct		cam_periph *cur_periph;
116 	path_id_t	path_id;
117 	target_id_t	target_id;
118 	lun_id_t	lun_id;
119 	cam_status	status;
120 	u_int		init_level;
121 	int s;
122 
123 	init_level = 0;
124 	/*
125 	 * Handle Hot-Plug scenarios.  If there is already a peripheral
126 	 * of our type assigned to this path, we are likely waiting for
127 	 * final close on an old, invalidated, peripheral.  If this is
128 	 * the case, queue up a deferred call to the peripheral's async
129 	 * handler.  If it looks like a mistaken re-alloation, complain.
130 	 */
131 	if ((periph = cam_periph_find(path, name)) != NULL) {
132 
133 		if ((periph->flags & CAM_PERIPH_INVALID) != 0
134 		 && (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) == 0) {
135 			periph->flags |= CAM_PERIPH_NEW_DEV_FOUND;
136 			periph->deferred_callback = ac_callback;
137 			periph->deferred_ac = code;
138 			return (CAM_REQ_INPROG);
139 		} else {
140 			printf("cam_periph_alloc: attempt to re-allocate "
141 			       "valid device %s%d rejected\n",
142 			       periph->periph_name, periph->unit_number);
143 		}
144 		return (CAM_REQ_INVALID);
145 	}
146 
147 	periph = (struct cam_periph *)malloc(sizeof(*periph), M_DEVBUF,
148 					     M_NOWAIT);
149 
150 	if (periph == NULL)
151 		return (CAM_RESRC_UNAVAIL);
152 
153 	init_level++;
154 
155 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
156 		if (strcmp((*p_drv)->driver_name, name) == 0)
157 			break;
158 	}
159 
160 	path_id = xpt_path_path_id(path);
161 	target_id = xpt_path_target_id(path);
162 	lun_id = xpt_path_lun_id(path);
163 	bzero(periph, sizeof(*periph));
164 	cam_init_pinfo(&periph->pinfo);
165 	periph->periph_start = periph_start;
166 	periph->periph_dtor = periph_dtor;
167 	periph->periph_oninval = periph_oninvalidate;
168 	periph->type = type;
169 	periph->periph_name = name;
170 	periph->unit_number = camperiphunit(*p_drv, path_id, target_id, lun_id);
171 	periph->immediate_priority = CAM_PRIORITY_NONE;
172 	periph->refcount = 0;
173 	SLIST_INIT(&periph->ccb_list);
174 	status = xpt_create_path(&path, periph, path_id, target_id, lun_id);
175 	if (status != CAM_REQ_CMP)
176 		goto failure;
177 
178 	periph->path = path;
179 	init_level++;
180 
181 	status = xpt_add_periph(periph);
182 
183 	if (status != CAM_REQ_CMP)
184 		goto failure;
185 
186 	s = splsoftcam();
187 	cur_periph = TAILQ_FIRST(&(*p_drv)->units);
188 	while (cur_periph != NULL
189 	    && cur_periph->unit_number < periph->unit_number)
190 		cur_periph = TAILQ_NEXT(cur_periph, unit_links);
191 
192 	if (cur_periph != NULL)
193 		TAILQ_INSERT_BEFORE(cur_periph, periph, unit_links);
194 	else {
195 		TAILQ_INSERT_TAIL(&(*p_drv)->units, periph, unit_links);
196 		(*p_drv)->generation++;
197 	}
198 
199 	splx(s);
200 
201 	init_level++;
202 
203 	status = periph_ctor(periph, arg);
204 
205 	if (status == CAM_REQ_CMP)
206 		init_level++;
207 
208 failure:
209 	switch (init_level) {
210 	case 4:
211 		/* Initialized successfully */
212 		break;
213 	case 3:
214 		s = splsoftcam();
215 		TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
216 		splx(s);
217 		xpt_remove_periph(periph);
218 		/* FALLTHROUGH */
219 	case 2:
220 		xpt_free_path(periph->path);
221 		/* FALLTHROUGH */
222 	case 1:
223 		free(periph, M_DEVBUF);
224 		/* FALLTHROUGH */
225 	case 0:
226 		/* No cleanup to perform. */
227 		break;
228 	default:
229 		panic("cam_periph_alloc: Unkown init level");
230 	}
231 	return(status);
232 }
233 
234 /*
235  * Find a peripheral structure with the specified path, target, lun,
236  * and (optionally) type.  If the name is NULL, this function will return
237  * the first peripheral driver that matches the specified path.
238  */
239 struct cam_periph *
240 cam_periph_find(struct cam_path *path, char *name)
241 {
242 	struct periph_driver **p_drv;
243 	struct cam_periph *periph;
244 	int s;
245 
246 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
247 
248 		if (name != NULL && (strcmp((*p_drv)->driver_name, name) != 0))
249 			continue;
250 
251 		s = splsoftcam();
252 		TAILQ_FOREACH(periph, &(*p_drv)->units, unit_links) {
253 			if (xpt_path_comp(periph->path, path) == 0) {
254 				splx(s);
255 				return(periph);
256 			}
257 		}
258 		splx(s);
259 		if (name != NULL)
260 			return(NULL);
261 	}
262 	return(NULL);
263 }
264 
265 cam_status
266 cam_periph_acquire(struct cam_periph *periph)
267 {
268 	int s;
269 
270 	if (periph == NULL)
271 		return(CAM_REQ_CMP_ERR);
272 
273 	s = splsoftcam();
274 	periph->refcount++;
275 	splx(s);
276 
277 	return(CAM_REQ_CMP);
278 }
279 
280 void
281 cam_periph_release(struct cam_periph *periph)
282 {
283 	int s;
284 
285 	if (periph == NULL)
286 		return;
287 
288 	s = splsoftcam();
289 	if ((--periph->refcount == 0)
290 	 && (periph->flags & CAM_PERIPH_INVALID)) {
291 		camperiphfree(periph);
292 	}
293 	splx(s);
294 
295 }
296 
297 /*
298  * Look for the next unit number that is not currently in use for this
299  * peripheral type starting at "newunit".  Also exclude unit numbers that
300  * are reserved by for future "hardwiring" unless we already know that this
301  * is a potential wired device.  Only assume that the device is "wired" the
302  * first time through the loop since after that we'll be looking at unit
303  * numbers that did not match a wiring entry.
304  */
305 static u_int
306 camperiphnextunit(struct periph_driver *p_drv, u_int newunit, int wired,
307 		  path_id_t pathid, target_id_t target, lun_id_t lun)
308 {
309 	struct	cam_periph *periph;
310 	char	*periph_name;
311 	int	s;
312 	int	i, val, dunit, r;
313 	const char *dname, *strval;
314 
315 	s = splsoftcam();
316 	periph_name = p_drv->driver_name;
317 	for (;;newunit++) {
318 
319 		for (periph = TAILQ_FIRST(&p_drv->units);
320 		     periph != NULL && periph->unit_number != newunit;
321 		     periph = TAILQ_NEXT(periph, unit_links))
322 			;
323 
324 		if (periph != NULL && periph->unit_number == newunit) {
325 			if (wired != 0) {
326 				xpt_print_path(periph->path);
327 				printf("Duplicate Wired Device entry!\n");
328 				xpt_print_path(periph->path);
329 				printf("Second device (%s device at scbus%d "
330 				       "target %d lun %d) will not be wired\n",
331 				       periph_name, pathid, target, lun);
332 				wired = 0;
333 			}
334 			continue;
335 		}
336 		if (wired)
337 			break;
338 
339 		/*
340 		 * Don't match entries like "da 4" as a wired down
341 		 * device, but do match entries like "da 4 target 5"
342 		 * or even "da 4 scbus 1".
343 		 */
344 		i = 0;
345 		dname = periph_name;
346 		for (;;) {
347 			r = resource_find_dev(&i, dname, &dunit, NULL, NULL);
348 			if (r != 0)
349 				break;
350 			/* if no "target" and no specific scbus, skip */
351 			if (resource_int_value(dname, dunit, "target", &val) &&
352 			    (resource_string_value(dname, dunit, "at",&strval)||
353 			     strcmp(strval, "scbus") == 0))
354 				continue;
355 			if (newunit == dunit)
356 				break;
357 		}
358 		if (r != 0)
359 			break;
360 	}
361 	splx(s);
362 	return (newunit);
363 }
364 
365 static u_int
366 camperiphunit(struct periph_driver *p_drv, path_id_t pathid,
367 	      target_id_t target, lun_id_t lun)
368 {
369 	u_int	unit;
370 	int	wired, i, val, dunit;
371 	const char *dname, *strval;
372 	char	pathbuf[32], *periph_name;
373 
374 	periph_name = p_drv->driver_name;
375 	snprintf(pathbuf, sizeof(pathbuf), "scbus%d", pathid);
376 	unit = 0;
377 	i = 0;
378 	dname = periph_name;
379 	for (wired = 0; resource_find_dev(&i, dname, &dunit, NULL, NULL) == 0;
380 	     wired = 0) {
381 		if (resource_string_value(dname, dunit, "at", &strval) == 0) {
382 			if (strcmp(strval, pathbuf) != 0)
383 				continue;
384 			wired++;
385 		}
386 		if (resource_int_value(dname, dunit, "target", &val) == 0) {
387 			if (val != target)
388 				continue;
389 			wired++;
390 		}
391 		if (resource_int_value(dname, dunit, "lun", &val) == 0) {
392 			if (val != lun)
393 				continue;
394 			wired++;
395 		}
396 		if (wired != 0) {
397 			unit = dunit;
398 			break;
399 		}
400 	}
401 
402 	/*
403 	 * Either start from 0 looking for the next unit or from
404 	 * the unit number given in the resource config.  This way,
405 	 * if we have wildcard matches, we don't return the same
406 	 * unit number twice.
407 	 */
408 	unit = camperiphnextunit(p_drv, unit, wired, pathid, target, lun);
409 
410 	return (unit);
411 }
412 
413 void
414 cam_periph_invalidate(struct cam_periph *periph)
415 {
416 	int s;
417 
418 	s = splsoftcam();
419 	/*
420 	 * We only call this routine the first time a peripheral is
421 	 * invalidated.  The oninvalidate() routine is always called at
422 	 * splsoftcam().
423 	 */
424 	if (((periph->flags & CAM_PERIPH_INVALID) == 0)
425 	 && (periph->periph_oninval != NULL))
426 		periph->periph_oninval(periph);
427 
428 	periph->flags |= CAM_PERIPH_INVALID;
429 	periph->flags &= ~CAM_PERIPH_NEW_DEV_FOUND;
430 
431 	if (periph->refcount == 0)
432 		camperiphfree(periph);
433 	else if (periph->refcount < 0)
434 		printf("cam_invalidate_periph: refcount < 0!!\n");
435 	splx(s);
436 }
437 
438 static void
439 camperiphfree(struct cam_periph *periph)
440 {
441 	int s;
442 	struct periph_driver **p_drv;
443 
444 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
445 		if (strcmp((*p_drv)->driver_name, periph->periph_name) == 0)
446 			break;
447 	}
448 
449 	if (periph->periph_dtor != NULL)
450 		periph->periph_dtor(periph);
451 
452 	s = splsoftcam();
453 	TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
454 	(*p_drv)->generation++;
455 	splx(s);
456 
457 	xpt_remove_periph(periph);
458 
459 	if (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) {
460 		union ccb ccb;
461 		void *arg;
462 
463 		switch (periph->deferred_ac) {
464 		case AC_FOUND_DEVICE:
465 			ccb.ccb_h.func_code = XPT_GDEV_TYPE;
466 			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
467 			xpt_action(&ccb);
468 			arg = &ccb;
469 			break;
470 		case AC_PATH_REGISTERED:
471 			ccb.ccb_h.func_code = XPT_PATH_INQ;
472 			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
473 			xpt_action(&ccb);
474 			arg = &ccb;
475 			break;
476 		default:
477 			arg = NULL;
478 			break;
479 		}
480 		periph->deferred_callback(NULL, periph->deferred_ac,
481 					  periph->path, arg);
482 	}
483 	xpt_free_path(periph->path);
484 	free(periph, M_DEVBUF);
485 }
486 
487 /*
488  * Wait interruptibly for an exclusive lock.
489  */
490 int
491 cam_periph_lock(struct cam_periph *periph, int priority)
492 {
493 	int error;
494 
495 	/*
496 	 * Increment the reference count on the peripheral
497 	 * while we wait for our lock attempt to succeed
498 	 * to ensure the peripheral doesn't disappear out
499 	 * from under us while we sleep.
500 	 */
501 	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
502 		return(ENXIO);
503 
504 	while ((periph->flags & CAM_PERIPH_LOCKED) != 0) {
505 		periph->flags |= CAM_PERIPH_LOCK_WANTED;
506 		if ((error = tsleep(periph, priority, "caplck", 0)) != 0) {
507 			cam_periph_release(periph);
508 			return error;
509 		}
510 	}
511 
512 	periph->flags |= CAM_PERIPH_LOCKED;
513 	return 0;
514 }
515 
516 /*
517  * Unlock and wake up any waiters.
518  */
519 void
520 cam_periph_unlock(struct cam_periph *periph)
521 {
522 	periph->flags &= ~CAM_PERIPH_LOCKED;
523 	if ((periph->flags & CAM_PERIPH_LOCK_WANTED) != 0) {
524 		periph->flags &= ~CAM_PERIPH_LOCK_WANTED;
525 		wakeup(periph);
526 	}
527 
528 	cam_periph_release(periph);
529 }
530 
531 /*
532  * Map user virtual pointers into kernel virtual address space, so we can
533  * access the memory.  This won't work on physical pointers, for now it's
534  * up to the caller to check for that.  (XXX KDM -- should we do that here
535  * instead?)  This also only works for up to MAXPHYS memory.  Since we use
536  * buffers to map stuff in and out, we're limited to the buffer size.
537  */
538 int
539 cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
540 {
541 	int numbufs, i, j;
542 	int flags[CAM_PERIPH_MAXMAPS];
543 	u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
544 	u_int32_t lengths[CAM_PERIPH_MAXMAPS];
545 	u_int32_t dirs[CAM_PERIPH_MAXMAPS];
546 
547 	switch(ccb->ccb_h.func_code) {
548 	case XPT_DEV_MATCH:
549 		if (ccb->cdm.match_buf_len == 0) {
550 			printf("cam_periph_mapmem: invalid match buffer "
551 			       "length 0\n");
552 			return(EINVAL);
553 		}
554 		if (ccb->cdm.pattern_buf_len > 0) {
555 			data_ptrs[0] = (u_int8_t **)&ccb->cdm.patterns;
556 			lengths[0] = ccb->cdm.pattern_buf_len;
557 			dirs[0] = CAM_DIR_OUT;
558 			data_ptrs[1] = (u_int8_t **)&ccb->cdm.matches;
559 			lengths[1] = ccb->cdm.match_buf_len;
560 			dirs[1] = CAM_DIR_IN;
561 			numbufs = 2;
562 		} else {
563 			data_ptrs[0] = (u_int8_t **)&ccb->cdm.matches;
564 			lengths[0] = ccb->cdm.match_buf_len;
565 			dirs[0] = CAM_DIR_IN;
566 			numbufs = 1;
567 		}
568 		break;
569 	case XPT_SCSI_IO:
570 	case XPT_CONT_TARGET_IO:
571 		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_NONE)
572 			return(0);
573 
574 		data_ptrs[0] = &ccb->csio.data_ptr;
575 		lengths[0] = ccb->csio.dxfer_len;
576 		dirs[0] = ccb->ccb_h.flags & CAM_DIR_MASK;
577 		numbufs = 1;
578 		break;
579 	default:
580 		return(EINVAL);
581 		break; /* NOTREACHED */
582 	}
583 
584 	/*
585 	 * Check the transfer length and permissions first, so we don't
586 	 * have to unmap any previously mapped buffers.
587 	 */
588 	for (i = 0; i < numbufs; i++) {
589 
590 		flags[i] = 0;
591 
592 		/*
593 		 * The userland data pointer passed in may not be page
594 		 * aligned.  vmapbuf() truncates the address to a page
595 		 * boundary, so if the address isn't page aligned, we'll
596 		 * need enough space for the given transfer length, plus
597 		 * whatever extra space is necessary to make it to the page
598 		 * boundary.
599 		 */
600 		if ((lengths[i] +
601 		    (((vm_offset_t)(*data_ptrs[i])) & PAGE_MASK)) > DFLTPHYS){
602 			printf("cam_periph_mapmem: attempt to map %lu bytes, "
603 			       "which is greater than DFLTPHYS(%d)\n",
604 			       (long)(lengths[i] +
605 			       (((vm_offset_t)(*data_ptrs[i])) & PAGE_MASK)),
606 			       DFLTPHYS);
607 			return(E2BIG);
608 		}
609 
610 		if (dirs[i] & CAM_DIR_OUT) {
611 			flags[i] = BIO_WRITE;
612 		}
613 
614 		if (dirs[i] & CAM_DIR_IN) {
615 			flags[i] = BIO_READ;
616 		}
617 
618 	}
619 
620 	/* this keeps the current process from getting swapped */
621 	/*
622 	 * XXX KDM should I use P_NOSWAP instead?
623 	 */
624 	PHOLD(curproc);
625 
626 	for (i = 0; i < numbufs; i++) {
627 		/*
628 		 * Get the buffer.
629 		 */
630 		mapinfo->bp[i] = getpbuf(NULL);
631 
632 		/* save the buffer's data address */
633 		mapinfo->bp[i]->b_saveaddr = mapinfo->bp[i]->b_data;
634 
635 		/* put our pointer in the data slot */
636 		mapinfo->bp[i]->b_data = *data_ptrs[i];
637 
638 		/* set the transfer length, we know it's < DFLTPHYS */
639 		mapinfo->bp[i]->b_bufsize = lengths[i];
640 
641 		/* set the flags */
642 		mapinfo->bp[i]->b_flags = B_PHYS;
643 
644 		/* set the direction */
645 		mapinfo->bp[i]->b_iocmd = flags[i];
646 
647 		/*
648 		 * Map the buffer into kernel memory.
649 		 *
650 		 * Note that useracc() alone is not a  sufficient test.
651 		 * vmapbuf() can still fail due to a smaller file mapped
652 		 * into a larger area of VM, or if userland races against
653 		 * vmapbuf() after the useracc() check.
654 		 */
655 		if (vmapbuf(mapinfo->bp[i]) < 0) {
656 			for (j = 0; j < i; ++j) {
657 				*data_ptrs[j] = mapinfo->bp[j]->b_saveaddr;
658 				vunmapbuf(mapinfo->bp[j]);
659 				mapinfo->bp[j]->b_flags &= ~B_PHYS;
660 				relpbuf(mapinfo->bp[j], NULL);
661 			}
662 			mapinfo->bp[i]->b_flags &= ~B_PHYS;
663 			relpbuf(mapinfo->bp[i], NULL);
664 			PRELE(curproc);
665 			return(EACCES);
666 		}
667 
668 		/* set our pointer to the new mapped area */
669 		*data_ptrs[i] = mapinfo->bp[i]->b_data;
670 
671 		mapinfo->num_bufs_used++;
672 	}
673 
674 	return(0);
675 }
676 
677 /*
678  * Unmap memory segments mapped into kernel virtual address space by
679  * cam_periph_mapmem().
680  */
681 void
682 cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
683 {
684 	int numbufs, i;
685 	u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
686 
687 	if (mapinfo->num_bufs_used <= 0) {
688 		/* allow ourselves to be swapped once again */
689 		PRELE(curproc);
690 		return;
691 	}
692 
693 	switch (ccb->ccb_h.func_code) {
694 	case XPT_DEV_MATCH:
695 		numbufs = min(mapinfo->num_bufs_used, 2);
696 
697 		if (numbufs == 1) {
698 			data_ptrs[0] = (u_int8_t **)&ccb->cdm.matches;
699 		} else {
700 			data_ptrs[0] = (u_int8_t **)&ccb->cdm.patterns;
701 			data_ptrs[1] = (u_int8_t **)&ccb->cdm.matches;
702 		}
703 		break;
704 	case XPT_SCSI_IO:
705 	case XPT_CONT_TARGET_IO:
706 		data_ptrs[0] = &ccb->csio.data_ptr;
707 		numbufs = min(mapinfo->num_bufs_used, 1);
708 		break;
709 	default:
710 		/* allow ourselves to be swapped once again */
711 		PRELE(curproc);
712 		return;
713 		break; /* NOTREACHED */
714 	}
715 
716 	for (i = 0; i < numbufs; i++) {
717 		/* Set the user's pointer back to the original value */
718 		*data_ptrs[i] = mapinfo->bp[i]->b_saveaddr;
719 
720 		/* unmap the buffer */
721 		vunmapbuf(mapinfo->bp[i]);
722 
723 		/* clear the flags we set above */
724 		mapinfo->bp[i]->b_flags &= ~B_PHYS;
725 
726 		/* release the buffer */
727 		relpbuf(mapinfo->bp[i], NULL);
728 	}
729 
730 	/* allow ourselves to be swapped once again */
731 	PRELE(curproc);
732 }
733 
734 union ccb *
735 cam_periph_getccb(struct cam_periph *periph, u_int32_t priority)
736 {
737 	struct ccb_hdr *ccb_h;
738 	int s;
739 
740 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdgetccb\n"));
741 
742 	s = splsoftcam();
743 
744 	while (SLIST_FIRST(&periph->ccb_list) == NULL) {
745 		if (periph->immediate_priority > priority)
746 			periph->immediate_priority = priority;
747 		xpt_schedule(periph, priority);
748 		if ((SLIST_FIRST(&periph->ccb_list) != NULL)
749 		 && (SLIST_FIRST(&periph->ccb_list)->pinfo.priority == priority))
750 			break;
751 		tsleep(&periph->ccb_list, PRIBIO, "cgticb", 0);
752 	}
753 
754 	ccb_h = SLIST_FIRST(&periph->ccb_list);
755 	SLIST_REMOVE_HEAD(&periph->ccb_list, periph_links.sle);
756 	splx(s);
757 	return ((union ccb *)ccb_h);
758 }
759 
760 void
761 cam_periph_ccbwait(union ccb *ccb)
762 {
763 	int s;
764 
765 	s = splsoftcam();
766 	if ((ccb->ccb_h.pinfo.index != CAM_UNQUEUED_INDEX)
767 	 || ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_INPROG))
768 		tsleep(&ccb->ccb_h.cbfcnp, PRIBIO, "cbwait", 0);
769 
770 	splx(s);
771 }
772 
773 int
774 cam_periph_ioctl(struct cam_periph *periph, int cmd, caddr_t addr,
775 		 int (*error_routine)(union ccb *ccb,
776 				      cam_flags camflags,
777 				      u_int32_t sense_flags))
778 {
779 	union ccb 	     *ccb;
780 	int 		     error;
781 	int		     found;
782 
783 	error = found = 0;
784 
785 	switch(cmd){
786 	case CAMGETPASSTHRU:
787 		ccb = cam_periph_getccb(periph, /* priority */ 1);
788 		xpt_setup_ccb(&ccb->ccb_h,
789 			      ccb->ccb_h.path,
790 			      /*priority*/1);
791 		ccb->ccb_h.func_code = XPT_GDEVLIST;
792 
793 		/*
794 		 * Basically, the point of this is that we go through
795 		 * getting the list of devices, until we find a passthrough
796 		 * device.  In the current version of the CAM code, the
797 		 * only way to determine what type of device we're dealing
798 		 * with is by its name.
799 		 */
800 		while (found == 0) {
801 			ccb->cgdl.index = 0;
802 			ccb->cgdl.status = CAM_GDEVLIST_MORE_DEVS;
803 			while (ccb->cgdl.status == CAM_GDEVLIST_MORE_DEVS) {
804 
805 				/* we want the next device in the list */
806 				xpt_action(ccb);
807 				if (strncmp(ccb->cgdl.periph_name,
808 				    "pass", 4) == 0){
809 					found = 1;
810 					break;
811 				}
812 			}
813 			if ((ccb->cgdl.status == CAM_GDEVLIST_LAST_DEVICE) &&
814 			    (found == 0)) {
815 				ccb->cgdl.periph_name[0] = '\0';
816 				ccb->cgdl.unit_number = 0;
817 				break;
818 			}
819 		}
820 
821 		/* copy the result back out */
822 		bcopy(ccb, addr, sizeof(union ccb));
823 
824 		/* and release the ccb */
825 		xpt_release_ccb(ccb);
826 
827 		break;
828 	default:
829 		error = ENOTTY;
830 		break;
831 	}
832 	return(error);
833 }
834 
835 int
836 cam_periph_runccb(union ccb *ccb,
837 		  int (*error_routine)(union ccb *ccb,
838 				       cam_flags camflags,
839 				       u_int32_t sense_flags),
840 		  cam_flags camflags, u_int32_t sense_flags,
841 		  struct devstat *ds)
842 {
843 	int error;
844 
845 	error = 0;
846 
847 	/*
848 	 * If the user has supplied a stats structure, and if we understand
849 	 * this particular type of ccb, record the transaction start.
850 	 */
851 	if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
852 		devstat_start_transaction(ds, NULL);
853 
854 	xpt_action(ccb);
855 
856 	do {
857 		cam_periph_ccbwait(ccb);
858 		if ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_CMP)
859 			error = 0;
860 		else if (error_routine != NULL)
861 			error = (*error_routine)(ccb, camflags, sense_flags);
862 		else
863 			error = 0;
864 
865 	} while (error == ERESTART);
866 
867 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
868 		cam_release_devq(ccb->ccb_h.path,
869 				 /* relsim_flags */0,
870 				 /* openings */0,
871 				 /* timeout */0,
872 				 /* getcount_only */ FALSE);
873 
874 	if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
875 		devstat_end_transaction(ds,
876 					ccb->csio.dxfer_len,
877 					ccb->csio.tag_action & 0xf,
878 					((ccb->ccb_h.flags & CAM_DIR_MASK) ==
879 					CAM_DIR_NONE) ?  DEVSTAT_NO_DATA :
880 					(ccb->ccb_h.flags & CAM_DIR_OUT) ?
881 					DEVSTAT_WRITE :
882 					DEVSTAT_READ, NULL, NULL);
883 
884 	return(error);
885 }
886 
887 void
888 cam_freeze_devq(struct cam_path *path)
889 {
890 	struct ccb_hdr ccb_h;
891 
892 	xpt_setup_ccb(&ccb_h, path, /*priority*/1);
893 	ccb_h.func_code = XPT_NOOP;
894 	ccb_h.flags = CAM_DEV_QFREEZE;
895 	xpt_action((union ccb *)&ccb_h);
896 }
897 
898 u_int32_t
899 cam_release_devq(struct cam_path *path, u_int32_t relsim_flags,
900 		 u_int32_t openings, u_int32_t timeout,
901 		 int getcount_only)
902 {
903 	struct ccb_relsim crs;
904 
905 	xpt_setup_ccb(&crs.ccb_h, path,
906 		      /*priority*/1);
907 	crs.ccb_h.func_code = XPT_REL_SIMQ;
908 	crs.ccb_h.flags = getcount_only ? CAM_DEV_QFREEZE : 0;
909 	crs.release_flags = relsim_flags;
910 	crs.openings = openings;
911 	crs.release_timeout = timeout;
912 	xpt_action((union ccb *)&crs);
913 	return (crs.qfrozen_cnt);
914 }
915 
916 #define saved_ccb_ptr ppriv_ptr0
917 static void
918 camperiphdone(struct cam_periph *periph, union ccb *done_ccb)
919 {
920 	union ccb      *saved_ccb;
921 	cam_status	status;
922 	int		frozen;
923 	int		sense;
924 	struct scsi_start_stop_unit *scsi_cmd;
925 	u_int32_t	relsim_flags, timeout;
926 	u_int32_t	qfrozen_cnt;
927 	int		xpt_done_ccb;
928 
929 	xpt_done_ccb = FALSE;
930 	status = done_ccb->ccb_h.status;
931 	frozen = (status & CAM_DEV_QFRZN) != 0;
932 	sense  = (status & CAM_AUTOSNS_VALID) != 0;
933 	status &= CAM_STATUS_MASK;
934 
935 	timeout = 0;
936 	relsim_flags = 0;
937 	saved_ccb = (union ccb *)done_ccb->ccb_h.saved_ccb_ptr;
938 
939 	/*
940 	 * Unfreeze the queue once if it is already frozen..
941 	 */
942 	if (frozen != 0) {
943 		qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
944 					      /*relsim_flags*/0,
945 					      /*openings*/0,
946 					      /*timeout*/0,
947 					      /*getcount_only*/0);
948 	}
949 
950 	switch (status) {
951 	case CAM_REQ_CMP:
952 	{
953 		/*
954 		 * If we have successfully taken a device from the not
955 		 * ready to ready state, re-scan the device and re-get
956 		 * the inquiry information.  Many devices (mostly disks)
957 		 * don't properly report their inquiry information unless
958 		 * they are spun up.
959 		 *
960 		 * If we manually retrieved sense into a CCB and got
961 		 * something other than "NO SENSE" send the updated CCB
962 		 * back to the client via xpt_done() to be processed via
963 		 * the error recovery code again.
964 		 */
965 		if (done_ccb->ccb_h.func_code == XPT_SCSI_IO) {
966 			scsi_cmd = (struct scsi_start_stop_unit *)
967 					&done_ccb->csio.cdb_io.cdb_bytes;
968 
969 		 	if (scsi_cmd->opcode == START_STOP_UNIT)
970 				xpt_async(AC_INQ_CHANGED,
971 					  done_ccb->ccb_h.path, NULL);
972 			if (scsi_cmd->opcode == REQUEST_SENSE) {
973 				u_int sense_key;
974 
975 				sense_key = saved_ccb->csio.sense_data.flags;
976 				sense_key &= SSD_KEY;
977 				if (sense_key != SSD_KEY_NO_SENSE) {
978 					saved_ccb->ccb_h.flags |=
979 					    CAM_AUTOSNS_VALID;
980 					xpt_print_path(saved_ccb->ccb_h.path);
981 					printf("Recovered Sense\n");
982 #if 0
983 					scsi_sense_print(&saved_ccb->csio);
984 #endif
985 					cam_error_print(saved_ccb, CAM_ESF_ALL,
986 							CAM_EPF_ALL);
987 					xpt_done_ccb = TRUE;
988 				}
989 			}
990 		}
991 		bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
992 		      sizeof(union ccb));
993 
994 		periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
995 
996 		if (xpt_done_ccb == FALSE)
997 			xpt_action(done_ccb);
998 
999 		break;
1000 	}
1001 	case CAM_SCSI_STATUS_ERROR:
1002 		scsi_cmd = (struct scsi_start_stop_unit *)
1003 				&done_ccb->csio.cdb_io.cdb_bytes;
1004 		if (sense != 0) {
1005 			struct scsi_sense_data *sense;
1006 			int    error_code, sense_key, asc, ascq;
1007 
1008 			sense = &done_ccb->csio.sense_data;
1009 			scsi_extract_sense(sense, &error_code,
1010 					   &sense_key, &asc, &ascq);
1011 
1012 			/*
1013 	 		 * If the error is "invalid field in CDB",
1014 			 * and the load/eject flag is set, turn the
1015 			 * flag off and try again.  This is just in
1016 			 * case the drive in question barfs on the
1017 			 * load eject flag.  The CAM code should set
1018 			 * the load/eject flag by default for
1019 			 * removable media.
1020 			 */
1021 
1022 			/* XXX KDM
1023 			 * Should we check to see what the specific
1024 			 * scsi status is??  Or does it not matter
1025 			 * since we already know that there was an
1026 			 * error, and we know what the specific
1027 			 * error code was, and we know what the
1028 			 * opcode is..
1029 			 */
1030 			if ((scsi_cmd->opcode == START_STOP_UNIT) &&
1031 			    ((scsi_cmd->how & SSS_LOEJ) != 0) &&
1032 			     (asc == 0x24) && (ascq == 0x00) &&
1033 			     (done_ccb->ccb_h.retry_count > 0)) {
1034 
1035 				scsi_cmd->how &= ~SSS_LOEJ;
1036 
1037 				xpt_action(done_ccb);
1038 
1039 			} else if (done_ccb->ccb_h.retry_count > 1) {
1040 				/*
1041 				 * In this case, the error recovery
1042 				 * command failed, but we've got
1043 				 * some retries left on it.  Give
1044 				 * it another try.
1045 				 */
1046 
1047 				/* set the timeout to .5 sec */
1048 				relsim_flags =
1049 					RELSIM_RELEASE_AFTER_TIMEOUT;
1050 				timeout = 500;
1051 
1052 				xpt_action(done_ccb);
1053 
1054 				break;
1055 
1056 			} else {
1057 				/*
1058 				 * Perform the final retry with the original
1059 				 * CCB so that final error processing is
1060 				 * performed by the owner of the CCB.
1061 				 */
1062 				bcopy(done_ccb->ccb_h.saved_ccb_ptr,
1063 				      done_ccb, sizeof(union ccb));
1064 
1065 				periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1066 
1067 				xpt_action(done_ccb);
1068 			}
1069 		} else {
1070 			/*
1071 			 * Eh??  The command failed, but we don't
1072 			 * have any sense.  What's up with that?
1073 			 * Fire the CCB again to return it to the
1074 			 * caller.
1075 			 */
1076 			bcopy(done_ccb->ccb_h.saved_ccb_ptr,
1077 			      done_ccb, sizeof(union ccb));
1078 
1079 			periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1080 
1081 			xpt_action(done_ccb);
1082 
1083 		}
1084 		break;
1085 	default:
1086 		bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
1087 		      sizeof(union ccb));
1088 
1089 		periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1090 
1091 		xpt_action(done_ccb);
1092 
1093 		break;
1094 	}
1095 
1096 	/* decrement the retry count */
1097 	/*
1098 	 * XXX This isn't appropriate in all cases.  Restructure,
1099 	 *     so that the retry count is only decremented on an
1100 	 *     actual retry.  Remeber that the orignal ccb had its
1101 	 *     retry count dropped before entering recovery, so
1102 	 *     doing it again is a bug.
1103 	 */
1104 	if (done_ccb->ccb_h.retry_count > 0)
1105 		done_ccb->ccb_h.retry_count--;
1106 
1107 	qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
1108 				      /*relsim_flags*/relsim_flags,
1109 				      /*openings*/0,
1110 				      /*timeout*/timeout,
1111 				      /*getcount_only*/0);
1112 	if (xpt_done_ccb == TRUE)
1113 		(*done_ccb->ccb_h.cbfcnp)(periph, done_ccb);
1114 }
1115 
1116 /*
1117  * Generic Async Event handler.  Peripheral drivers usually
1118  * filter out the events that require personal attention,
1119  * and leave the rest to this function.
1120  */
1121 void
1122 cam_periph_async(struct cam_periph *periph, u_int32_t code,
1123 		 struct cam_path *path, void *arg)
1124 {
1125 	switch (code) {
1126 	case AC_LOST_DEVICE:
1127 		cam_periph_invalidate(periph);
1128 		break;
1129 	case AC_SENT_BDR:
1130 	case AC_BUS_RESET:
1131 	{
1132 		cam_periph_bus_settle(periph, scsi_delay);
1133 		break;
1134 	}
1135 	default:
1136 		break;
1137 	}
1138 }
1139 
1140 void
1141 cam_periph_bus_settle(struct cam_periph *periph, u_int bus_settle)
1142 {
1143 	struct ccb_getdevstats cgds;
1144 
1145 	xpt_setup_ccb(&cgds.ccb_h, periph->path, /*priority*/1);
1146 	cgds.ccb_h.func_code = XPT_GDEV_STATS;
1147 	xpt_action((union ccb *)&cgds);
1148 	cam_periph_freeze_after_event(periph, &cgds.last_reset, bus_settle);
1149 }
1150 
1151 void
1152 cam_periph_freeze_after_event(struct cam_periph *periph,
1153 			      struct timeval* event_time, u_int duration_ms)
1154 {
1155 	struct timeval delta;
1156 	struct timeval duration_tv;
1157 	int s;
1158 
1159 	s = splclock();
1160 	microtime(&delta);
1161 	splx(s);
1162 	timevalsub(&delta, event_time);
1163 	duration_tv.tv_sec = duration_ms / 1000;
1164 	duration_tv.tv_usec = (duration_ms % 1000) * 1000;
1165 	if (timevalcmp(&delta, &duration_tv, <)) {
1166 		timevalsub(&duration_tv, &delta);
1167 
1168 		duration_ms = duration_tv.tv_sec * 1000;
1169 		duration_ms += duration_tv.tv_usec / 1000;
1170 		cam_freeze_devq(periph->path);
1171 		cam_release_devq(periph->path,
1172 				RELSIM_RELEASE_AFTER_TIMEOUT,
1173 				/*reduction*/0,
1174 				/*timeout*/duration_ms,
1175 				/*getcount_only*/0);
1176 	}
1177 
1178 }
1179 
1180 static int
1181 camperiphscsistatuserror(union ccb *ccb, cam_flags camflags,
1182 			 u_int32_t sense_flags, union ccb *save_ccb,
1183 			 int *openings, u_int32_t *relsim_flags,
1184 			 u_int32_t *timeout)
1185 {
1186 	int error;
1187 
1188 	switch (ccb->csio.scsi_status) {
1189 	case SCSI_STATUS_OK:
1190 	case SCSI_STATUS_COND_MET:
1191 	case SCSI_STATUS_INTERMED:
1192 	case SCSI_STATUS_INTERMED_COND_MET:
1193 		error = 0;
1194 		break;
1195 	case SCSI_STATUS_CMD_TERMINATED:
1196 	case SCSI_STATUS_CHECK_COND:
1197 		error = camperiphscsisenseerror(ccb,
1198 					        camflags,
1199 					        sense_flags,
1200 					        save_ccb,
1201 					        openings,
1202 					        relsim_flags,
1203 					        timeout);
1204 		break;
1205 	case SCSI_STATUS_QUEUE_FULL:
1206 	{
1207 		/* no decrement */
1208 		struct ccb_getdevstats cgds;
1209 
1210 		/*
1211 		 * First off, find out what the current
1212 		 * transaction counts are.
1213 		 */
1214 		xpt_setup_ccb(&cgds.ccb_h,
1215 			      ccb->ccb_h.path,
1216 			      /*priority*/1);
1217 		cgds.ccb_h.func_code = XPT_GDEV_STATS;
1218 		xpt_action((union ccb *)&cgds);
1219 
1220 		/*
1221 		 * If we were the only transaction active, treat
1222 		 * the QUEUE FULL as if it were a BUSY condition.
1223 		 */
1224 		if (cgds.dev_active != 0) {
1225 			int total_openings;
1226 
1227 			/*
1228 		 	 * Reduce the number of openings to
1229 			 * be 1 less than the amount it took
1230 			 * to get a queue full bounded by the
1231 			 * minimum allowed tag count for this
1232 			 * device.
1233 		 	 */
1234 			total_openings = cgds.dev_active + cgds.dev_openings;
1235 			*openings = cgds.dev_active;
1236 			if (*openings < cgds.mintags)
1237 				*openings = cgds.mintags;
1238 			if (*openings < total_openings)
1239 				*relsim_flags = RELSIM_ADJUST_OPENINGS;
1240 			else {
1241 				/*
1242 				 * Some devices report queue full for
1243 				 * temporary resource shortages.  For
1244 				 * this reason, we allow a minimum
1245 				 * tag count to be entered via a
1246 				 * quirk entry to prevent the queue
1247 				 * count on these devices from falling
1248 				 * to a pessimisticly low value.  We
1249 				 * still wait for the next successful
1250 				 * completion, however, before queueing
1251 				 * more transactions to the device.
1252 				 */
1253 				*relsim_flags = RELSIM_RELEASE_AFTER_CMDCMPLT;
1254 			}
1255 			*timeout = 0;
1256 			error = ERESTART;
1257 			if (bootverbose) {
1258 				xpt_print_path(ccb->ccb_h.path);
1259 				printf("Queue Full\n");
1260 			}
1261 			break;
1262 		}
1263 		/* FALLTHROUGH */
1264 	}
1265 	case SCSI_STATUS_BUSY:
1266 		/*
1267 		 * Restart the queue after either another
1268 		 * command completes or a 1 second timeout.
1269 		 */
1270 		if (bootverbose) {
1271 			xpt_print_path(ccb->ccb_h.path);
1272 			printf("Device Busy\n");
1273 		}
1274 	 	if (ccb->ccb_h.retry_count > 0) {
1275 	 		ccb->ccb_h.retry_count--;
1276 			error = ERESTART;
1277 			*relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT
1278 				      | RELSIM_RELEASE_AFTER_CMDCMPLT;
1279 			*timeout = 1000;
1280 		} else {
1281 			error = EIO;
1282 		}
1283 		break;
1284 	case SCSI_STATUS_RESERV_CONFLICT:
1285 		xpt_print_path(ccb->ccb_h.path);
1286 		printf("Reservation Conflict\n");
1287 		error = EIO;
1288 		break;
1289 	default:
1290 		xpt_print_path(ccb->ccb_h.path);
1291 		printf("SCSI Status 0x%x\n", ccb->csio.scsi_status);
1292 		error = EIO;
1293 		break;
1294 	}
1295 	return (error);
1296 }
1297 
1298 static int
1299 camperiphscsisenseerror(union ccb *ccb, cam_flags camflags,
1300 			u_int32_t sense_flags, union ccb *save_ccb,
1301 		       int *openings, u_int32_t *relsim_flags,
1302 		       u_int32_t *timeout)
1303 {
1304 	struct cam_periph *periph;
1305 	int error;
1306 
1307 	periph = xpt_path_periph(ccb->ccb_h.path);
1308 	if (periph->flags & CAM_PERIPH_RECOVERY_INPROG) {
1309 
1310 		/*
1311 		 * If error recovery is already in progress, don't attempt
1312 		 * to process this error, but requeue it unconditionally
1313 		 * and attempt to process it once error recovery has
1314 		 * completed.  This failed command is probably related to
1315 		 * the error that caused the currently active error recovery
1316 		 * action so our  current recovery efforts should also
1317 		 * address this command.  Be aware that the error recovery
1318 		 * code assumes that only one recovery action is in progress
1319 		 * on a particular peripheral instance at any given time
1320 		 * (e.g. only one saved CCB for error recovery) so it is
1321 		 * imperitive that we don't violate this assumption.
1322 		 */
1323 		error = ERESTART;
1324 	} else {
1325 		scsi_sense_action err_action;
1326 		struct ccb_getdev cgd;
1327 		const char *action_string;
1328 		union ccb* print_ccb;
1329 
1330 		/* A description of the error recovery action performed */
1331 		action_string = NULL;
1332 
1333 		/*
1334 		 * The location of the orignal ccb
1335 		 * for sense printing purposes.
1336 		 */
1337 		print_ccb = ccb;
1338 
1339 		/*
1340 		 * Grab the inquiry data for this device.
1341 		 */
1342 		xpt_setup_ccb(&cgd.ccb_h, ccb->ccb_h.path, /*priority*/ 1);
1343 		cgd.ccb_h.func_code = XPT_GDEV_TYPE;
1344 		xpt_action((union ccb *)&cgd);
1345 
1346 		if ((ccb->ccb_h.status & CAM_AUTOSNS_VALID) != 0)
1347 			err_action = scsi_error_action(&ccb->csio,
1348 						       &cgd.inq_data,
1349 						       sense_flags);
1350 		else if ((ccb->ccb_h.flags & CAM_DIS_AUTOSENSE) == 0)
1351 			err_action = SS_REQSENSE;
1352 		else
1353 			err_action = SS_RETRY|SSQ_DECREMENT_COUNT|EIO;
1354 
1355 		error = err_action & SS_ERRMASK;
1356 
1357 		/*
1358 		 * If the recovery action will consume a retry,
1359 		 * make sure we actually have retries available.
1360 		 */
1361 		if ((err_action & SSQ_DECREMENT_COUNT) != 0) {
1362 		 	if (ccb->ccb_h.retry_count > 0)
1363 		 		ccb->ccb_h.retry_count--;
1364 			else {
1365 				action_string = "Retries Exhausted";
1366 				goto sense_error_done;
1367 			}
1368 		}
1369 
1370 		if ((err_action & SS_MASK) >= SS_START) {
1371 			/*
1372 			 * Do common portions of commands that
1373 			 * use recovery CCBs.
1374 			 */
1375 			if (save_ccb == NULL) {
1376 				action_string = "No recovery CCB supplied";
1377 				goto sense_error_done;
1378 			}
1379 			bcopy(ccb, save_ccb, sizeof(*save_ccb));
1380 			print_ccb = save_ccb;
1381 			periph->flags |= CAM_PERIPH_RECOVERY_INPROG;
1382 		}
1383 
1384 		switch (err_action & SS_MASK) {
1385 		case SS_NOP:
1386 			action_string = "No Recovery Action Needed";
1387 			error = 0;
1388 			break;
1389 		case SS_RETRY:
1390 			action_string = "Retrying Command (per Sense Data)";
1391 			error = ERESTART;
1392 			break;
1393 		case SS_FAIL:
1394 			action_string = "Unretryable error";
1395 			break;
1396 		case SS_START:
1397 		{
1398 			int le;
1399 
1400 			/*
1401 			 * Send a start unit command to the device, and
1402 			 * then retry the command.
1403 			 */
1404 			action_string = "Attempting to Start Unit";
1405 
1406 			/*
1407 			 * Check for removable media and set
1408 			 * load/eject flag appropriately.
1409 			 */
1410 			if (SID_IS_REMOVABLE(&cgd.inq_data))
1411 				le = TRUE;
1412 			else
1413 				le = FALSE;
1414 
1415 			scsi_start_stop(&ccb->csio,
1416 					/*retries*/1,
1417 					camperiphdone,
1418 					MSG_SIMPLE_Q_TAG,
1419 					/*start*/TRUE,
1420 					/*load/eject*/le,
1421 					/*immediate*/FALSE,
1422 					SSD_FULL_SIZE,
1423 					/*timeout*/50000);
1424 			break;
1425 		}
1426 		case SS_TUR:
1427 		{
1428 			/*
1429 			 * Send a Test Unit Ready to the device.
1430 			 * If the 'many' flag is set, we send 120
1431 			 * test unit ready commands, one every half
1432 			 * second.  Otherwise, we just send one TUR.
1433 			 * We only want to do this if the retry
1434 			 * count has not been exhausted.
1435 			 */
1436 			int retries;
1437 
1438 			if ((err_action & SSQ_MANY) != 0) {
1439 				action_string = "Polling device for readiness";
1440 				retries = 120;
1441 			} else {
1442 				action_string = "Testing device for readiness";
1443 				retries = 1;
1444 			}
1445 			scsi_test_unit_ready(&ccb->csio,
1446 					     retries,
1447 					     camperiphdone,
1448 					     MSG_SIMPLE_Q_TAG,
1449 					     SSD_FULL_SIZE,
1450 					     /*timeout*/5000);
1451 
1452 			/*
1453 			 * Accomplish our 500ms delay by deferring
1454 			 * the release of our device queue appropriately.
1455 			 */
1456 			*relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1457 			*timeout = 500;
1458 			break;
1459 		}
1460 		case SS_REQSENSE:
1461 		{
1462 			/*
1463 			 * Send a Request Sense to the device.  We
1464 			 * assume that we are in a contingent allegiance
1465 			 * condition so we do not tag this request.
1466 			 */
1467 			scsi_request_sense(&ccb->csio, /*retries*/1,
1468 					   camperiphdone,
1469 					   &save_ccb->csio.sense_data,
1470 					   sizeof(save_ccb->csio.sense_data),
1471 					   CAM_TAG_ACTION_NONE,
1472 					   /*sense_len*/SSD_FULL_SIZE,
1473 					   /*timeout*/5000);
1474 			break;
1475 		}
1476 		default:
1477 			panic("Unhandled error action %x", err_action);
1478 		}
1479 
1480 		if ((err_action & SS_MASK) >= SS_START) {
1481 			/*
1482 			 * Drop the priority to 0 so that the recovery
1483 			 * CCB is the first to execute.  Freeze the queue
1484 			 * after this command is sent so that we can
1485 			 * restore the old csio and have it queued in
1486 			 * the proper order before we release normal
1487 			 * transactions to the device.
1488 			 */
1489 			ccb->ccb_h.pinfo.priority = 0;
1490 			ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
1491 			ccb->ccb_h.saved_ccb_ptr = save_ccb;
1492 			error = ERESTART;
1493 		}
1494 
1495 sense_error_done:
1496 		if ((err_action & SSQ_PRINT_SENSE) != 0
1497 		 && (ccb->ccb_h.status & CAM_AUTOSNS_VALID) != 0) {
1498 			cam_error_print(print_ccb, CAM_ESF_ALL, CAM_EPF_ALL);
1499 			xpt_print_path(ccb->ccb_h.path);
1500 			if (bootverbose)
1501 				scsi_sense_print(&print_ccb->csio);
1502 			printf("%s\n", action_string);
1503 		}
1504 	}
1505 	return (error);
1506 }
1507 
1508 /*
1509  * Generic error handler.  Peripheral drivers usually filter
1510  * out the errors that they handle in a unique mannor, then
1511  * call this function.
1512  */
1513 int
1514 cam_periph_error(union ccb *ccb, cam_flags camflags,
1515 		 u_int32_t sense_flags, union ccb *save_ccb)
1516 {
1517 	const char *action_string;
1518 	cam_status  status;
1519 	int	    frozen;
1520 	int	    error, printed = 0;
1521 	int         openings;
1522 	u_int32_t   relsim_flags;
1523 	u_int32_t   timeout;
1524 
1525 	action_string = NULL;
1526 	status = ccb->ccb_h.status;
1527 	frozen = (status & CAM_DEV_QFRZN) != 0;
1528 	status &= CAM_STATUS_MASK;
1529 	openings = relsim_flags = 0;
1530 
1531 	switch (status) {
1532 	case CAM_REQ_CMP:
1533 		error = 0;
1534 		break;
1535 	case CAM_SCSI_STATUS_ERROR:
1536 		error = camperiphscsistatuserror(ccb,
1537 						 camflags,
1538 						 sense_flags,
1539 						 save_ccb,
1540 						 &openings,
1541 						 &relsim_flags,
1542 						 &timeout);
1543 		break;
1544 	case CAM_AUTOSENSE_FAIL:
1545 		xpt_print_path(ccb->ccb_h.path);
1546 		printf("AutoSense Failed\n");
1547 		error = EIO;	/* we have to kill the command */
1548 		break;
1549 	case CAM_REQ_CMP_ERR:
1550 		if (bootverbose && printed == 0) {
1551 			xpt_print_path(ccb->ccb_h.path);
1552 			printf("Request completed with CAM_REQ_CMP_ERR\n");
1553 			printed++;
1554 		}
1555 		/* FALLTHROUGH */
1556 	case CAM_CMD_TIMEOUT:
1557 		if (bootverbose && printed == 0) {
1558 			xpt_print_path(ccb->ccb_h.path);
1559 			printf("Command timed out\n");
1560 			printed++;
1561 		}
1562 		/* FALLTHROUGH */
1563 	case CAM_UNEXP_BUSFREE:
1564 		if (bootverbose && printed == 0) {
1565 			xpt_print_path(ccb->ccb_h.path);
1566 			printf("Unexpected Bus Free\n");
1567 			printed++;
1568 		}
1569 		/* FALLTHROUGH */
1570 	case CAM_UNCOR_PARITY:
1571 		if (bootverbose && printed == 0) {
1572 			xpt_print_path(ccb->ccb_h.path);
1573 			printf("Uncorrected Parity Error\n");
1574 			printed++;
1575 		}
1576 		/* FALLTHROUGH */
1577 	case CAM_DATA_RUN_ERR:
1578 		if (bootverbose && printed == 0) {
1579 			xpt_print_path(ccb->ccb_h.path);
1580 			printf("Data Overrun\n");
1581 			printed++;
1582 		}
1583 		error = EIO;	/* we have to kill the command */
1584 		/* decrement the number of retries */
1585 		if (ccb->ccb_h.retry_count > 0) {
1586 			ccb->ccb_h.retry_count--;
1587 			error = ERESTART;
1588 		} else {
1589 			action_string = "Retries Exausted";
1590 			error = EIO;
1591 		}
1592 		break;
1593 	case CAM_UA_ABORT:
1594 	case CAM_UA_TERMIO:
1595 	case CAM_MSG_REJECT_REC:
1596 		/* XXX Don't know that these are correct */
1597 		error = EIO;
1598 		break;
1599 	case CAM_SEL_TIMEOUT:
1600 	{
1601 		struct cam_path *newpath;
1602 
1603 		if ((camflags & CAM_RETRY_SELTO) != 0) {
1604 			if (ccb->ccb_h.retry_count > 0) {
1605 
1606 				ccb->ccb_h.retry_count--;
1607 				error = ERESTART;
1608 				if (bootverbose && printed == 0) {
1609 					xpt_print_path(ccb->ccb_h.path);
1610 					printf("Selection Timeout\n");
1611 					printed++;
1612 				}
1613 
1614 				/*
1615 				 * Wait a second to give the device
1616 				 * time to recover before we try again.
1617 				 */
1618 				relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1619 				timeout = 1000;
1620 				break;
1621 			}
1622 		}
1623 		error = ENXIO;
1624 		/* Should we do more if we can't create the path?? */
1625 		if (xpt_create_path(&newpath, xpt_path_periph(ccb->ccb_h.path),
1626 				    xpt_path_path_id(ccb->ccb_h.path),
1627 				    xpt_path_target_id(ccb->ccb_h.path),
1628 				    CAM_LUN_WILDCARD) != CAM_REQ_CMP)
1629 			break;
1630 
1631 		/*
1632 		 * Let peripheral drivers know that this device has gone
1633 		 * away.
1634 		 */
1635 		xpt_async(AC_LOST_DEVICE, newpath, NULL);
1636 		xpt_free_path(newpath);
1637 		break;
1638 	}
1639 	case CAM_REQ_INVALID:
1640 	case CAM_PATH_INVALID:
1641 	case CAM_DEV_NOT_THERE:
1642 	case CAM_NO_HBA:
1643 	case CAM_PROVIDE_FAIL:
1644 	case CAM_REQ_TOO_BIG:
1645 		error = EINVAL;
1646 		break;
1647 	case CAM_SCSI_BUS_RESET:
1648 	case CAM_BDR_SENT:
1649 		/*
1650 		 * Commands that repeatedly timeout and cause these
1651 		 * kinds of error recovery actions, should return
1652 		 * CAM_CMD_TIMEOUT, which allows us to safely assume
1653 		 * that this command was an innocent bystander to
1654 		 * these events and should be unconditionally
1655 		 * retried.
1656 		 */
1657 		if (bootverbose && printed == 0) {
1658 			xpt_print_path(ccb->ccb_h.path);
1659 			if (status == CAM_BDR_SENT)
1660 				printf("Bus Device Reset sent\n");
1661 			else
1662 				printf("Bus Reset issued\n");
1663 			printed++;
1664 		}
1665 		/* FALLTHROUGH */
1666 	case CAM_REQUEUE_REQ:
1667 		/* Unconditional requeue */
1668 		error = ERESTART;
1669 		if (bootverbose && printed == 0) {
1670 			xpt_print_path(ccb->ccb_h.path);
1671 			printf("Request Requeued\n");
1672 			printed++;
1673 		}
1674 		break;
1675 	case CAM_RESRC_UNAVAIL:
1676 	case CAM_BUSY:
1677 		/* timeout??? */
1678 	default:
1679 		/* decrement the number of retries */
1680 		if (ccb->ccb_h.retry_count > 0) {
1681 			ccb->ccb_h.retry_count--;
1682 			error = ERESTART;
1683 			if (bootverbose && printed == 0) {
1684 				xpt_print_path(ccb->ccb_h.path);
1685 				printf("CAM Status 0x%x\n", status);
1686 				printed++;
1687 			}
1688 		} else {
1689 			error = EIO;
1690 			action_string = "Retries Exhausted";
1691 		}
1692 		break;
1693 	}
1694 
1695 	/* Attempt a retry */
1696 	if (error == ERESTART || error == 0) {
1697 		if (frozen != 0)
1698 			ccb->ccb_h.status &= ~CAM_DEV_QFRZN;
1699 
1700 		if (error == ERESTART) {
1701 			action_string = "Retrying Command";
1702 			xpt_action(ccb);
1703 		}
1704 
1705 		if (frozen != 0)
1706 			cam_release_devq(ccb->ccb_h.path,
1707 					 relsim_flags,
1708 					 openings,
1709 					 timeout,
1710 					 /*getcount_only*/0);
1711 	}
1712 
1713 	/*
1714 	 * If we have and error and are booting verbosely, whine
1715 	 * *unless* this was a non-retryable selection timeout.
1716 	 */
1717 	if (error != 0 && bootverbose &&
1718 	    !(status == CAM_SEL_TIMEOUT && (camflags & CAM_RETRY_SELTO) == 0)) {
1719 
1720 
1721 		if (action_string == NULL)
1722 			action_string = "Unretryable Error";
1723 		if (error != ERESTART) {
1724 			xpt_print_path(ccb->ccb_h.path);
1725 			printf("error %d\n", error);
1726 		}
1727 		xpt_print_path(ccb->ccb_h.path);
1728 		printf("%s\n", action_string);
1729 	}
1730 
1731 	return (error);
1732 }
1733