xref: /dragonfly/sys/bus/cam/cam_periph.c (revision b990a6be)
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  * $FreeBSD: src/sys/cam/cam_periph.c,v 1.70 2008/02/12 11:07:33 raj Exp $
30  */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/types.h>
35 #include <sys/malloc.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/buf.h>
39 #include <sys/proc.h>
40 #include <sys/devicestat.h>
41 #include <sys/bus.h>
42 #include <vm/vm.h>
43 #include <vm/vm_extern.h>
44 
45 #include <sys/thread2.h>
46 
47 #include "cam.h"
48 #include "cam_ccb.h"
49 #include "cam_xpt_periph.h"
50 #include "cam_periph.h"
51 #include "cam_debug.h"
52 #include "cam_sim.h"
53 
54 #include <bus/cam/scsi/scsi_all.h>
55 #include <bus/cam/scsi/scsi_message.h>
56 #include <bus/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 				      struct cam_sim *sim, path_id_t pathid,
64 				      target_id_t target, 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 static void cam_periph_unmapbufs(struct cam_periph_map_info *mapinfo,
83 				 u_int8_t ***data_ptrs, int numbufs);
84 
85 static int nperiph_drivers;
86 struct periph_driver **periph_drivers;
87 
88 MALLOC_DEFINE(M_CAMPERIPH, "CAM periph", "CAM peripheral buffers");
89 
90 static int periph_selto_delay = 1000;
91 TUNABLE_INT("kern.cam.periph_selto_delay", &periph_selto_delay);
92 static int periph_noresrc_delay = 500;
93 TUNABLE_INT("kern.cam.periph_noresrc_delay", &periph_noresrc_delay);
94 static int periph_busy_delay = 500;
95 TUNABLE_INT("kern.cam.periph_busy_delay", &periph_busy_delay);
96 
97 
98 void
99 periphdriver_register(void *data)
100 {
101 	struct periph_driver **newdrivers, **old;
102 	int ndrivers;
103 
104 	ndrivers = nperiph_drivers + 2;
105 	newdrivers = kmalloc(sizeof(*newdrivers) * ndrivers, M_CAMPERIPH,
106 			     M_WAITOK);
107 	if (periph_drivers)
108 		bcopy(periph_drivers, newdrivers,
109 		      sizeof(*newdrivers) * nperiph_drivers);
110 	newdrivers[nperiph_drivers] = (struct periph_driver *)data;
111 	newdrivers[nperiph_drivers + 1] = NULL;
112 	old = periph_drivers;
113 	periph_drivers = newdrivers;
114 	if (old)
115 		kfree(old, M_CAMPERIPH);
116 	nperiph_drivers++;
117 }
118 
119 cam_status
120 cam_periph_alloc(periph_ctor_t *periph_ctor,
121 		 periph_oninv_t *periph_oninvalidate,
122 		 periph_dtor_t *periph_dtor, periph_start_t *periph_start,
123 		 char *name, cam_periph_type type, struct cam_path *path,
124 		 ac_callback_t *ac_callback, ac_code code, void *arg)
125 {
126 	struct		periph_driver **p_drv;
127 	struct		cam_sim *sim;
128 	struct		cam_periph *periph;
129 	struct		cam_periph *cur_periph;
130 	path_id_t	path_id;
131 	target_id_t	target_id;
132 	lun_id_t	lun_id;
133 	cam_status	status;
134 	u_int		init_level;
135 
136 	init_level = 0;
137 	/*
138 	 * Handle Hot-Plug scenarios.  If there is already a peripheral
139 	 * of our type assigned to this path, we are likely waiting for
140 	 * final close on an old, invalidated, peripheral.  If this is
141 	 * the case, queue up a deferred call to the peripheral's async
142 	 * handler.  If it looks like a mistaken re-allocation, complain.
143 	 */
144 	if ((periph = cam_periph_find(path, name)) != NULL) {
145 
146 		if ((periph->flags & CAM_PERIPH_INVALID) != 0
147 		 && (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) == 0) {
148 			periph->flags |= CAM_PERIPH_NEW_DEV_FOUND;
149 			periph->deferred_callback = ac_callback;
150 			periph->deferred_ac = code;
151 			return (CAM_REQ_INPROG);
152 		} else {
153 			kprintf("cam_periph_alloc: attempt to re-allocate "
154 			       "valid device %s%d rejected\n",
155 			       periph->periph_name, periph->unit_number);
156 		}
157 		return (CAM_REQ_INVALID);
158 	}
159 
160 	periph = kmalloc(sizeof(*periph), M_CAMPERIPH, M_INTWAIT | M_ZERO);
161 
162 	init_level++;	/* 1 */
163 
164 	xpt_lock_buses();
165 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
166 		if (strcmp((*p_drv)->driver_name, name) == 0)
167 			break;
168 	}
169 	xpt_unlock_buses();
170 
171 	sim = xpt_path_sim(path);
172 	CAM_SIM_LOCK(sim);
173 	path_id = xpt_path_path_id(path);
174 	target_id = xpt_path_target_id(path);
175 	lun_id = xpt_path_lun_id(path);
176 	cam_init_pinfo(&periph->pinfo);
177 	periph->periph_start = periph_start;
178 	periph->periph_dtor = periph_dtor;
179 	periph->periph_oninval = periph_oninvalidate;
180 	periph->type = type;
181 	periph->periph_name = name;
182 	periph->unit_number = camperiphunit(*p_drv, sim, path_id,
183 					    target_id, lun_id);
184 	periph->immediate_priority = CAM_PRIORITY_NONE;
185 	periph->refcount = 0;
186 	periph->sim = sim;
187 	SLIST_INIT(&periph->ccb_list);
188 	status = xpt_create_path(&path, periph, path_id, target_id, lun_id);
189 	if (status != CAM_REQ_CMP)
190 		goto failure;
191 
192 	init_level++;	/* 2 */
193 
194 	periph->path = path;
195 	status = xpt_add_periph(periph);
196 
197 	if (status != CAM_REQ_CMP)
198 		goto failure;
199 
200 	xpt_lock_buses();
201 	cur_periph = TAILQ_FIRST(&(*p_drv)->units);
202 	while (cur_periph != NULL
203 	    && cur_periph->unit_number < periph->unit_number)
204 		cur_periph = TAILQ_NEXT(cur_periph, unit_links);
205 
206 	if (cur_periph != NULL)
207 		TAILQ_INSERT_BEFORE(cur_periph, periph, unit_links);
208 	else {
209 		TAILQ_INSERT_TAIL(&(*p_drv)->units, periph, unit_links);
210 		(*p_drv)->generation++;
211 	}
212 	xpt_unlock_buses();
213 
214 	init_level++;
215 
216 	status = periph_ctor(periph, arg);
217 
218 	if (status == CAM_REQ_CMP)
219 		init_level++;
220 
221 failure:
222 	switch (init_level) {
223 	case 4:
224 		/* Initialized successfully */
225 		CAM_SIM_UNLOCK(sim);
226 		break;
227 	case 3:
228 		xpt_lock_buses();
229 		TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
230 		xpt_unlock_buses();
231 		xpt_remove_periph(periph);
232 		/* FALLTHROUGH */
233 	case 2:
234 		periph->path = NULL;
235 		/* FALLTHROUGH */
236 	case 1:
237 		CAM_SIM_UNLOCK(sim);	/* sim was retrieved from path */
238 		xpt_free_path(path);
239 		kfree(periph, M_CAMPERIPH);
240 		/* FALLTHROUGH */
241 	case 0:
242 		/* No cleanup to perform. */
243 		break;
244 	default:
245 		panic("cam_periph_alloc: Unknown init level");
246 	}
247 	return(status);
248 }
249 
250 /*
251  * Find a peripheral structure with the specified path, target, lun,
252  * and (optionally) type.  If the name is NULL, this function will return
253  * the first peripheral driver that matches the specified path.
254  */
255 struct cam_periph *
256 cam_periph_find(struct cam_path *path, char *name)
257 {
258 	struct periph_driver **p_drv;
259 	struct cam_periph *periph;
260 
261 	xpt_lock_buses();
262 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
263 		if (name != NULL && (strcmp((*p_drv)->driver_name, name) != 0))
264 			continue;
265 
266 		TAILQ_FOREACH(periph, &(*p_drv)->units, unit_links) {
267 			if (xpt_path_comp(periph->path, path) == 0) {
268 				xpt_unlock_buses();
269 				return(periph);
270 			}
271 		}
272 		if (name != NULL) {
273 			xpt_unlock_buses();
274 			return(NULL);
275 		}
276 	}
277 	xpt_unlock_buses();
278 	return(NULL);
279 }
280 
281 cam_status
282 cam_periph_acquire(struct cam_periph *periph)
283 {
284 	if (periph == NULL)
285 		return(CAM_REQ_CMP_ERR);
286 
287 	xpt_lock_buses();
288 	periph->refcount++;
289 	xpt_unlock_buses();
290 
291 	return(CAM_REQ_CMP);
292 }
293 
294 /*
295  * Release the peripheral.  The XPT is not locked and the SIM may or may
296  * not be locked on entry.
297  *
298  * The last release on a peripheral marked invalid frees it.  In this
299  * case we must be sure to hold both the XPT lock and the SIM lock,
300  * requiring a bit of fancy footwork if the SIM lock already happens
301  * to be held.
302  */
303 void
304 cam_periph_release(struct cam_periph *periph)
305 {
306 	struct cam_sim *sim;
307 	int doun;
308 
309 	while (periph) {
310 		/*
311 		 * First try the critical path case
312 		 */
313 		sim = periph->sim;
314 		xpt_lock_buses();
315 		if ((periph->flags & CAM_PERIPH_INVALID) == 0 ||
316 		    periph->refcount != 1) {
317 			--periph->refcount;
318 			xpt_unlock_buses();
319 			break;
320 		}
321 
322 		/*
323 		 * Otherwise we also need to free the peripheral and must
324 		 * acquire the sim lock and xpt lock in the correct order
325 		 * to do so.
326 		 *
327 		 * The condition must be re-checked after the locks have
328 		 * been reacquired.
329 		 */
330 		xpt_unlock_buses();
331 		doun = CAM_SIM_COND_LOCK(sim);
332 		xpt_lock_buses();
333 		--periph->refcount;
334 		if ((periph->flags & CAM_PERIPH_INVALID) &&
335 		    periph->refcount == 0) {
336 			camperiphfree(periph);
337 		}
338 		xpt_unlock_buses();
339 		CAM_SIM_COND_UNLOCK(sim, doun);
340 		break;
341 	}
342 }
343 
344 int
345 cam_periph_hold(struct cam_periph *periph, int flags)
346 {
347 	int error;
348 
349 	sim_lock_assert_owned(periph->sim->lock);
350 
351 	/*
352 	 * Increment the reference count on the peripheral
353 	 * while we wait for our lock attempt to succeed
354 	 * to ensure the peripheral doesn't disappear out
355 	 * from user us while we sleep.
356 	 */
357 
358 	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
359 		return (ENXIO);
360 
361 	while ((periph->flags & CAM_PERIPH_LOCKED) != 0) {
362 		periph->flags |= CAM_PERIPH_LOCK_WANTED;
363 		if ((error = sim_lock_sleep(periph, flags, "caplck", 0,
364 					    periph->sim->lock)) != 0) {
365 			cam_periph_release(periph);
366 			return (error);
367 		}
368 	}
369 
370 	periph->flags |= CAM_PERIPH_LOCKED;
371 	return (0);
372 }
373 
374 void
375 cam_periph_unhold(struct cam_periph *periph, int unlock)
376 {
377 	struct cam_sim *sim;
378 
379 	sim_lock_assert_owned(periph->sim->lock);
380 	periph->flags &= ~CAM_PERIPH_LOCKED;
381 	if ((periph->flags & CAM_PERIPH_LOCK_WANTED) != 0) {
382 		periph->flags &= ~CAM_PERIPH_LOCK_WANTED;
383 		wakeup(periph);
384 	}
385 	if (unlock) {
386 		sim = periph->sim;
387 		cam_periph_release(periph);
388 		/* periph may be garbage now */
389 		CAM_SIM_UNLOCK(sim);
390 	} else {
391 		cam_periph_release(periph);
392 	}
393 }
394 
395 /*
396  * Look for the next unit number that is not currently in use for this
397  * peripheral type starting at "newunit".  Also exclude unit numbers that
398  * are reserved by for future "hardwiring" unless we already know that this
399  * is a potential wired device.  Only assume that the device is "wired" the
400  * first time through the loop since after that we'll be looking at unit
401  * numbers that did not match a wiring entry.
402  */
403 static u_int
404 camperiphnextunit(struct periph_driver *p_drv, u_int newunit, int wired,
405 		  path_id_t pathid, target_id_t target, lun_id_t lun)
406 {
407 	struct	cam_periph *periph;
408 	char	*periph_name;
409 	int	i, val, dunit;
410 	const char *dname, *strval;
411 
412 	periph_name = p_drv->driver_name;
413 	for (;;newunit++) {
414 
415 		for (periph = TAILQ_FIRST(&p_drv->units);
416 		     periph != NULL && periph->unit_number != newunit;
417 		     periph = TAILQ_NEXT(periph, unit_links))
418 			;
419 
420 		if (periph != NULL && periph->unit_number == newunit) {
421 			if (wired != 0) {
422 				xpt_print(periph->path, "Duplicate Wired "
423 				    "Device entry!\n");
424 				xpt_print(periph->path, "Second device (%s "
425 				    "device at scbus%d target %d lun %d) will "
426 				    "not be wired\n", periph_name, pathid,
427 				    target, lun);
428 				wired = 0;
429 			}
430 			continue;
431 		}
432 		if (wired)
433 			break;
434 
435 		/*
436 		 * Don't match entries like "da 4" as a wired down
437 		 * device, but do match entries like "da 4 target 5"
438 		 * or even "da 4 scbus 1".
439 		 */
440 		i = -1;
441 		while ((i = resource_locate(i, periph_name)) != -1) {
442 			dname = resource_query_name(i);
443 			dunit = resource_query_unit(i);
444 			/* if no "target" and no specific scbus, skip */
445 			if (resource_int_value(dname, dunit, "target", &val) &&
446 			    (resource_string_value(dname, dunit, "at",&strval)||
447 			     strcmp(strval, "scbus") == 0))
448 				continue;
449 			if (newunit == dunit)
450 				break;
451 		}
452 		if (i == -1)
453 			break;
454 	}
455 	return (newunit);
456 }
457 
458 static u_int
459 camperiphunit(struct periph_driver *p_drv,
460 	      struct cam_sim *sim, path_id_t pathid,
461 	      target_id_t target, lun_id_t lun)
462 {
463 	u_int	unit;
464 	int	hit, i, val, dunit;
465 	const char *dname, *strval;
466 	char	pathbuf[32], *periph_name;
467 
468 	unit = 0;
469 
470 	periph_name = p_drv->driver_name;
471 	ksnprintf(pathbuf, sizeof(pathbuf), "scbus%d", pathid);
472 	i = -1;
473 	for (hit = 0; (i = resource_locate(i, periph_name)) != -1; hit = 0) {
474 		dname = resource_query_name(i);
475 		dunit = resource_query_unit(i);
476 		if (resource_string_value(dname, dunit, "at", &strval) == 0) {
477 			if (strcmp(strval, pathbuf) != 0)
478 				continue;
479 			hit++;
480 		}
481 		if (resource_int_value(dname, dunit, "target", &val) == 0) {
482 			if (val != target)
483 				continue;
484 			hit++;
485 		}
486 		if (resource_int_value(dname, dunit, "lun", &val) == 0) {
487 			if (val != lun)
488 				continue;
489 			hit++;
490 		}
491 		if (hit != 0) {
492 			unit = dunit;
493 			break;
494 		}
495 	}
496 
497 	/*
498 	 * If no wired units are in the kernel config do an auto unit
499 	 * start selection.  We want usb mass storage out of the way
500 	 * so it doesn't steal low numbered da%d slots from ahci, sili,
501 	 * or other scsi attachments.
502 	 */
503 	if (hit == 0 && sim) {
504 		if (strncmp(sim->sim_name, "umass", 4) == 0 && unit < 8)
505 			unit = 8;
506 	}
507 
508 	/*
509 	 * Either start from 0 looking for the next unit or from
510 	 * the unit number given in the resource config.  This way,
511 	 * if we have wildcard matches, we don't return the same
512 	 * unit number twice.
513 	 */
514 	unit = camperiphnextunit(p_drv, unit, /*wired*/hit, pathid,
515 				 target, lun);
516 
517 	return (unit);
518 }
519 
520 void
521 cam_periph_invalidate(struct cam_periph *periph)
522 {
523 	/*
524 	 * We only call this routine the first time a peripheral is
525 	 * invalidated.
526 	 */
527 	if (((periph->flags & CAM_PERIPH_INVALID) == 0)
528 	 && (periph->periph_oninval != NULL))
529 		periph->periph_oninval(periph);
530 
531 	periph->flags |= CAM_PERIPH_INVALID;
532 	periph->flags &= ~CAM_PERIPH_NEW_DEV_FOUND;
533 
534 	xpt_lock_buses();
535 	if (periph->refcount == 0)
536 		camperiphfree(periph);
537 	else if (periph->refcount < 0)
538 		kprintf("cam_invalidate_periph: refcount < 0!!\n");
539 	xpt_unlock_buses();
540 }
541 
542 static void
543 camperiphfree(struct cam_periph *periph)
544 {
545 	struct periph_driver **p_drv;
546 
547 	for (p_drv = periph_drivers; *p_drv != NULL; p_drv++) {
548 		if (strcmp((*p_drv)->driver_name, periph->periph_name) == 0)
549 			break;
550 	}
551 
552 	if (*p_drv == NULL) {
553 		kprintf("camperiphfree: attempt to free non-existent periph\n");
554 		return;
555 	}
556 
557 	TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
558 	(*p_drv)->generation++;
559 	xpt_unlock_buses();
560 
561 	if (periph->periph_dtor != NULL)
562 		periph->periph_dtor(periph);
563 	xpt_remove_periph(periph);
564 
565 	if (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) {
566 		union ccb ccb;
567 		void *arg;
568 
569 		switch (periph->deferred_ac) {
570 		case AC_FOUND_DEVICE:
571 			ccb.ccb_h.func_code = XPT_GDEV_TYPE;
572 			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
573 			xpt_action(&ccb);
574 			arg = &ccb;
575 			break;
576 		case AC_PATH_REGISTERED:
577 			ccb.ccb_h.func_code = XPT_PATH_INQ;
578 			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
579 			xpt_action(&ccb);
580 			arg = &ccb;
581 			break;
582 		default:
583 			arg = NULL;
584 			break;
585 		}
586 		periph->deferred_callback(NULL, periph->deferred_ac,
587 					  periph->path, arg);
588 	}
589 	xpt_free_path(periph->path);
590 	kfree(periph, M_CAMPERIPH);
591 	xpt_lock_buses();
592 }
593 
594 /*
595  * We don't map user pointers into KVM, instead we use pbufs.
596  *
597  * This won't work on physical pointers(?OLD), for now it's
598  * up to the caller to check for that.  (XXX KDM -- should we do that here
599  * instead?)  This also only works for up to MAXPHYS memory.  Since we use
600  * buffers to map stuff in and out, we're limited to the buffer size.
601  */
602 int
603 cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
604 {
605 	buf_cmd_t cmd[CAM_PERIPH_MAXMAPS];
606 	u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
607 	u_int32_t lengths[CAM_PERIPH_MAXMAPS];
608 	int numbufs;
609 	int error;
610 	int i;
611 	struct buf *bp;
612 
613 	switch(ccb->ccb_h.func_code) {
614 	case XPT_DEV_MATCH:
615 		if (ccb->cdm.match_buf_len == 0) {
616 			kprintf("cam_periph_mapmem: invalid match buffer "
617 			       "length 0\n");
618 			return(EINVAL);
619 		}
620 		if (ccb->cdm.pattern_buf_len > 0) {
621 			data_ptrs[0] = (void *)&ccb->cdm.patterns;
622 			lengths[0] = ccb->cdm.pattern_buf_len;
623 			mapinfo->dirs[0] = CAM_DIR_OUT;
624 			data_ptrs[1] = (void *)&ccb->cdm.matches;
625 			lengths[1] = ccb->cdm.match_buf_len;
626 			mapinfo->dirs[1] = CAM_DIR_IN;
627 			numbufs = 2;
628 		} else {
629 			data_ptrs[0] = (void *)&ccb->cdm.matches;
630 			lengths[0] = ccb->cdm.match_buf_len;
631 			mapinfo->dirs[0] = CAM_DIR_IN;
632 			numbufs = 1;
633 		}
634 		break;
635 	case XPT_SCSI_IO:
636 	case XPT_CONT_TARGET_IO:
637 		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_NONE)
638 			return(0);
639 
640 		data_ptrs[0] = &ccb->csio.data_ptr;
641 		lengths[0] = ccb->csio.dxfer_len;
642 		mapinfo->dirs[0] = ccb->ccb_h.flags & CAM_DIR_MASK;
643 		numbufs = 1;
644 		break;
645 	default:
646 		return(EINVAL);
647 		break; /* NOTREACHED */
648 	}
649 
650 	/*
651 	 * Check the transfer length and permissions first, so we don't
652 	 * have to unmap any previously mapped buffers.
653 	 */
654 	for (i = 0; i < numbufs; i++) {
655 		/*
656 		 * Its kinda bogus, we need a R+W command.  For now the
657 		 * buffer needs some sort of command.  Use BUF_CMD_WRITE
658 		 * to indicate a write and BUF_CMD_READ to indicate R+W.
659 		 */
660 		cmd[i] = BUF_CMD_WRITE;
661 
662 		if (lengths[i] > MAXPHYS) {
663 			kprintf("cam_periph_mapmem: attempt to map %lu bytes, "
664 			       "which is greater than MAXPHYS(%d)\n",
665 			       (long)(lengths[i] +
666 			       (((vm_offset_t)(*data_ptrs[i])) & PAGE_MASK)),
667 			       MAXPHYS);
668 			return(E2BIG);
669 		}
670 
671 		if (mapinfo->dirs[i] & CAM_DIR_OUT) {
672 			if (!useracc(*data_ptrs[i], lengths[i],
673 				     VM_PROT_READ)) {
674 				kprintf("cam_periph_mapmem: error, "
675 					"address %p, length %lu isn't "
676 					"user accessible for READ\n",
677 					(void *)*data_ptrs[i],
678 					(u_long)lengths[i]);
679 				return(EACCES);
680 			}
681 		}
682 
683 		if (mapinfo->dirs[i] & CAM_DIR_IN) {
684 			cmd[i] = BUF_CMD_READ;
685 			if (!useracc(*data_ptrs[i], lengths[i],
686 				     VM_PROT_WRITE)) {
687 				kprintf("cam_periph_mapmem: error, "
688 					"address %p, length %lu isn't "
689 					"user accessible for WRITE\n",
690 					(void *)*data_ptrs[i],
691 					(u_long)lengths[i]);
692 
693 				return(EACCES);
694 			}
695 		}
696 
697 	}
698 
699 	for (i = 0; i < numbufs; i++) {
700 		/*
701 		 * Get the buffer.
702 		 */
703 		bp = getpbuf_mem(NULL);
704 
705 		/* save the original user pointer */
706 		mapinfo->saved_ptrs[i] = *data_ptrs[i];
707 
708 		/* set the flags */
709 		bp->b_cmd = cmd[i];
710 
711 		/*
712 		 * Always bounce the I/O through kernel memory.
713 		 */
714 		bp->b_bcount = lengths[i];
715 		if (mapinfo->dirs[i] & CAM_DIR_OUT) {
716 			error = copyin(*data_ptrs[i], bp->b_data, bp->b_bcount);
717 		} else {
718 			error = 0;
719 		}
720 		if (error) {
721 			relpbuf(bp, NULL);
722 			cam_periph_unmapbufs(mapinfo, data_ptrs, i);
723 			mapinfo->num_bufs_used -= i;
724 			return(error);
725 		}
726 
727 		/* set our pointer to the new mapped area */
728 		*data_ptrs[i] = bp->b_data;
729 
730 		mapinfo->bp[i] = bp;
731 		mapinfo->num_bufs_used++;
732 	}
733 
734 	return(0);
735 }
736 
737 /*
738  * Unmap memory segments mapped into kernel virtual address space by
739  * cam_periph_mapmem().
740  */
741 void
742 cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
743 {
744 	int numbufs;
745 	u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
746 
747 	if (mapinfo->num_bufs_used <= 0) {
748 		/* allow ourselves to be swapped once again */
749 		return;
750 	}
751 
752 	switch (ccb->ccb_h.func_code) {
753 	case XPT_DEV_MATCH:
754 		numbufs = min(mapinfo->num_bufs_used, 2);
755 
756 		if (numbufs == 1) {
757 			data_ptrs[0] = (void *)&ccb->cdm.matches;
758 		} else {
759 			data_ptrs[0] = (void *)&ccb->cdm.patterns;
760 			data_ptrs[1] = (void *)&ccb->cdm.matches;
761 		}
762 		break;
763 	case XPT_SCSI_IO:
764 	case XPT_CONT_TARGET_IO:
765 		data_ptrs[0] = &ccb->csio.data_ptr;
766 		numbufs = min(mapinfo->num_bufs_used, 1);
767 		break;
768 	default:
769 		/* allow ourselves to be swapped once again */
770 		return;
771 		break; /* NOTREACHED */
772 	}
773 	cam_periph_unmapbufs(mapinfo, data_ptrs, numbufs);
774 }
775 
776 static void
777 cam_periph_unmapbufs(struct cam_periph_map_info *mapinfo,
778 		     u_int8_t ***data_ptrs, int numbufs)
779 {
780 	struct buf *bp;
781 	int i;
782 
783 	for (i = 0; i < numbufs; i++) {
784 		bp = mapinfo->bp[i];
785 
786 		/* Set the user's pointer back to the original value */
787 		*data_ptrs[i] = mapinfo->saved_ptrs[i];
788 
789 		if (mapinfo->dirs[i] & CAM_DIR_IN) {
790 			/* XXX return error */
791 			copyout(bp->b_data, *data_ptrs[i], bp->b_bcount);
792 		}
793 		relpbuf(bp, NULL);
794 		mapinfo->bp[i] = NULL;
795 	}
796 }
797 
798 union ccb *
799 cam_periph_getccb(struct cam_periph *periph, u_int32_t priority)
800 {
801 	struct ccb_hdr *ccb_h;
802 
803 	sim_lock_assert_owned(periph->sim->lock);
804 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdgetccb\n"));
805 
806 	while (SLIST_FIRST(&periph->ccb_list) == NULL) {
807 		if (periph->immediate_priority > priority)
808 			periph->immediate_priority = priority;
809 		xpt_schedule(periph, priority);
810 		if ((SLIST_FIRST(&periph->ccb_list) != NULL)
811 		 && (SLIST_FIRST(&periph->ccb_list)->pinfo.priority == priority))
812 			break;
813 		sim_lock_sleep(&periph->ccb_list, 0, "cgticb", 0,
814 			       periph->sim->lock);
815 	}
816 
817 	ccb_h = SLIST_FIRST(&periph->ccb_list);
818 	SLIST_REMOVE_HEAD(&periph->ccb_list, periph_links.sle);
819 	return ((union ccb *)ccb_h);
820 }
821 
822 void
823 cam_periph_ccbwait(union ccb *ccb)
824 {
825 	struct cam_sim *sim;
826 
827 	sim = xpt_path_sim(ccb->ccb_h.path);
828 	while ((ccb->ccb_h.pinfo.index != CAM_UNQUEUED_INDEX)
829 	 || ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_INPROG)) {
830 		sim_lock_sleep(&ccb->ccb_h.cbfcnp, 0, "cbwait", 0, sim->lock);
831 	}
832 }
833 
834 int
835 cam_periph_ioctl(struct cam_periph *periph, u_long cmd, caddr_t addr,
836 		 int (*error_routine)(union ccb *ccb,
837 				      cam_flags camflags,
838 				      u_int32_t sense_flags))
839 {
840 	union ccb 	     *ccb;
841 	int 		     error;
842 	int		     found;
843 
844 	error = found = 0;
845 
846 	switch(cmd){
847 	case CAMGETPASSTHRU:
848 		ccb = cam_periph_getccb(periph, /* priority */ 1);
849 		xpt_setup_ccb(&ccb->ccb_h,
850 			      ccb->ccb_h.path,
851 			      /*priority*/1);
852 		ccb->ccb_h.func_code = XPT_GDEVLIST;
853 
854 		/*
855 		 * Basically, the point of this is that we go through
856 		 * getting the list of devices, until we find a passthrough
857 		 * device.  In the current version of the CAM code, the
858 		 * only way to determine what type of device we're dealing
859 		 * with is by its name.
860 		 */
861 		while (found == 0) {
862 			ccb->cgdl.index = 0;
863 			ccb->cgdl.status = CAM_GDEVLIST_MORE_DEVS;
864 			while (ccb->cgdl.status == CAM_GDEVLIST_MORE_DEVS) {
865 
866 				/* we want the next device in the list */
867 				xpt_action(ccb);
868 				if (strncmp(ccb->cgdl.periph_name,
869 				    "pass", 4) == 0){
870 					found = 1;
871 					break;
872 				}
873 			}
874 			if ((ccb->cgdl.status == CAM_GDEVLIST_LAST_DEVICE) &&
875 			    (found == 0)) {
876 				ccb->cgdl.periph_name[0] = '\0';
877 				ccb->cgdl.unit_number = 0;
878 				break;
879 			}
880 		}
881 
882 		/* copy the result back out */
883 		bcopy(ccb, addr, sizeof(union ccb));
884 
885 		/* and release the ccb */
886 		xpt_release_ccb(ccb);
887 
888 		break;
889 	default:
890 		error = ENOTTY;
891 		break;
892 	}
893 	return(error);
894 }
895 
896 int
897 cam_periph_runccb(union ccb *ccb,
898 		  int (*error_routine)(union ccb *ccb,
899 				       cam_flags camflags,
900 				       u_int32_t sense_flags),
901 		  cam_flags camflags, u_int32_t sense_flags,
902 		  struct devstat *ds)
903 {
904 	struct cam_sim *sim;
905 	int error;
906 
907 	error = 0;
908 	sim = xpt_path_sim(ccb->ccb_h.path);
909 	sim_lock_assert_owned(sim->lock);
910 
911 	/*
912 	 * If the user has supplied a stats structure, and if we understand
913 	 * this particular type of ccb, record the transaction start.
914 	 */
915 	if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
916 		devstat_start_transaction(ds);
917 
918 	xpt_action(ccb);
919 
920 	do {
921 		cam_periph_ccbwait(ccb);
922 		if ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_CMP)
923 			error = 0;
924 		else if (error_routine != NULL)
925 			error = (*error_routine)(ccb, camflags, sense_flags);
926 		else
927 			error = 0;
928 
929 	} while (error == ERESTART);
930 
931 	if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
932 		cam_release_devq(ccb->ccb_h.path,
933 				 /* relsim_flags */0,
934 				 /* openings */0,
935 				 /* timeout */0,
936 				 /* getcount_only */ FALSE);
937 
938 	if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
939 		devstat_end_transaction(ds,
940 					ccb->csio.dxfer_len,
941 					ccb->csio.tag_action & 0xf,
942 					((ccb->ccb_h.flags & CAM_DIR_MASK) ==
943 					CAM_DIR_NONE) ?  DEVSTAT_NO_DATA :
944 					(ccb->ccb_h.flags & CAM_DIR_OUT) ?
945 					DEVSTAT_WRITE :
946 					DEVSTAT_READ);
947 
948 	return(error);
949 }
950 
951 void
952 cam_freeze_devq(struct cam_path *path)
953 {
954 	struct ccb_hdr ccb_h;
955 
956 	xpt_setup_ccb(&ccb_h, path, /*priority*/1);
957 	ccb_h.func_code = XPT_NOOP;
958 	ccb_h.flags = CAM_DEV_QFREEZE;
959 	xpt_action((union ccb *)&ccb_h);
960 }
961 
962 u_int32_t
963 cam_release_devq(struct cam_path *path, u_int32_t relsim_flags,
964 		 u_int32_t openings, u_int32_t timeout,
965 		 int getcount_only)
966 {
967 	struct ccb_relsim crs;
968 
969 	xpt_setup_ccb(&crs.ccb_h, path,
970 		      /*priority*/1);
971 	crs.ccb_h.func_code = XPT_REL_SIMQ;
972 	crs.ccb_h.flags = getcount_only ? CAM_DEV_QFREEZE : 0;
973 	crs.release_flags = relsim_flags;
974 	crs.openings = openings;
975 	crs.release_timeout = timeout;
976 	xpt_action((union ccb *)&crs);
977 	return (crs.qfrozen_cnt);
978 }
979 
980 #define saved_ccb_ptr ppriv_ptr0
981 static void
982 camperiphdone(struct cam_periph *periph, union ccb *done_ccb)
983 {
984 	union ccb      *saved_ccb;
985 	cam_status	status;
986 	int		frozen;
987 	int		sense;
988 	struct scsi_start_stop_unit *scsi_cmd;
989 	u_int32_t	relsim_flags, timeout;
990 	u_int32_t	qfrozen_cnt;
991 	int		xpt_done_ccb;
992 
993 	xpt_done_ccb = FALSE;
994 	status = done_ccb->ccb_h.status;
995 	frozen = (status & CAM_DEV_QFRZN) != 0;
996 	sense  = (status & CAM_AUTOSNS_VALID) != 0;
997 	status &= CAM_STATUS_MASK;
998 
999 	timeout = 0;
1000 	relsim_flags = 0;
1001 	saved_ccb = (union ccb *)done_ccb->ccb_h.saved_ccb_ptr;
1002 
1003 	/*
1004 	 * Unfreeze the queue once if it is already frozen..
1005 	 */
1006 	if (frozen != 0) {
1007 		qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
1008 					      /*relsim_flags*/0,
1009 					      /*openings*/0,
1010 					      /*timeout*/0,
1011 					      /*getcount_only*/0);
1012 	}
1013 
1014 	switch (status) {
1015 	case CAM_REQ_CMP:
1016 	{
1017 		/*
1018 		 * If we have successfully taken a device from the not
1019 		 * ready to ready state, re-scan the device and re-get
1020 		 * the inquiry information.  Many devices (mostly disks)
1021 		 * don't properly report their inquiry information unless
1022 		 * they are spun up.
1023 		 *
1024 		 * If we manually retrieved sense into a CCB and got
1025 		 * something other than "NO SENSE" send the updated CCB
1026 		 * back to the client via xpt_done() to be processed via
1027 		 * the error recovery code again.
1028 		 */
1029 		if (done_ccb->ccb_h.func_code == XPT_SCSI_IO) {
1030 			scsi_cmd = (struct scsi_start_stop_unit *)
1031 					&done_ccb->csio.cdb_io.cdb_bytes;
1032 
1033 		 	if (scsi_cmd->opcode == START_STOP_UNIT)
1034 				xpt_async(AC_INQ_CHANGED,
1035 					  done_ccb->ccb_h.path, NULL);
1036 			if (scsi_cmd->opcode == REQUEST_SENSE) {
1037 				u_int sense_key;
1038 
1039 				sense_key = saved_ccb->csio.sense_data.flags;
1040 				sense_key &= SSD_KEY;
1041 				if (sense_key != SSD_KEY_NO_SENSE) {
1042 					saved_ccb->ccb_h.status |=
1043 					    CAM_AUTOSNS_VALID;
1044 #if 0
1045 					xpt_print(saved_ccb->ccb_h.path,
1046 					    "Recovered Sense\n");
1047 					scsi_sense_print(&saved_ccb->csio);
1048 					cam_error_print(saved_ccb, CAM_ESF_ALL,
1049 							CAM_EPF_ALL);
1050 #endif
1051 					xpt_done_ccb = TRUE;
1052 				}
1053 			}
1054 		}
1055 		bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
1056 		      sizeof(union ccb));
1057 
1058 		periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1059 
1060 		if (xpt_done_ccb == FALSE)
1061 			xpt_action(done_ccb);
1062 
1063 		break;
1064 	}
1065 	case CAM_SCSI_STATUS_ERROR:
1066 		scsi_cmd = (struct scsi_start_stop_unit *)
1067 				&done_ccb->csio.cdb_io.cdb_bytes;
1068 		if (sense != 0) {
1069 			struct ccb_getdev cgd;
1070 			struct scsi_sense_data *sense;
1071 			int    error_code, sense_key, asc, ascq;
1072 			scsi_sense_action err_action;
1073 
1074 			sense = &done_ccb->csio.sense_data;
1075 			scsi_extract_sense(sense, &error_code,
1076 					   &sense_key, &asc, &ascq);
1077 
1078 			/*
1079 			 * Grab the inquiry data for this device.
1080 			 */
1081 			xpt_setup_ccb(&cgd.ccb_h, done_ccb->ccb_h.path,
1082 				      /*priority*/ 1);
1083 			cgd.ccb_h.func_code = XPT_GDEV_TYPE;
1084 			xpt_action((union ccb *)&cgd);
1085 			err_action = scsi_error_action(&done_ccb->csio,
1086 						       &cgd.inq_data, 0);
1087 
1088 			/*
1089 	 		 * If the error is "invalid field in CDB",
1090 			 * and the load/eject flag is set, turn the
1091 			 * flag off and try again.  This is just in
1092 			 * case the drive in question barfs on the
1093 			 * load eject flag.  The CAM code should set
1094 			 * the load/eject flag by default for
1095 			 * removable media.
1096 			 */
1097 
1098 			/* XXX KDM
1099 			 * Should we check to see what the specific
1100 			 * scsi status is??  Or does it not matter
1101 			 * since we already know that there was an
1102 			 * error, and we know what the specific
1103 			 * error code was, and we know what the
1104 			 * opcode is..
1105 			 */
1106 			if ((scsi_cmd->opcode == START_STOP_UNIT) &&
1107 			    ((scsi_cmd->how & SSS_LOEJ) != 0) &&
1108 			     (asc == 0x24) && (ascq == 0x00) &&
1109 			     (done_ccb->ccb_h.retry_count > 0)) {
1110 
1111 				scsi_cmd->how &= ~SSS_LOEJ;
1112 
1113 				xpt_action(done_ccb);
1114 
1115 			} else if ((done_ccb->ccb_h.retry_count > 1)
1116 				&& ((err_action & SS_MASK) != SS_FAIL)) {
1117 
1118 				/*
1119 				 * In this case, the error recovery
1120 				 * command failed, but we've got
1121 				 * some retries left on it.  Give
1122 				 * it another try unless this is an
1123 				 * unretryable error.
1124 				 */
1125 
1126 				/* set the timeout to .5 sec */
1127 				relsim_flags =
1128 					RELSIM_RELEASE_AFTER_TIMEOUT;
1129 				timeout = 500;
1130 
1131 				xpt_action(done_ccb);
1132 
1133 				break;
1134 
1135 			} else {
1136 				/*
1137 				 * Perform the final retry with the original
1138 				 * CCB so that final error processing is
1139 				 * performed by the owner of the CCB.
1140 				 */
1141 				bcopy(done_ccb->ccb_h.saved_ccb_ptr,
1142 				      done_ccb, sizeof(union ccb));
1143 
1144 				periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1145 
1146 				xpt_action(done_ccb);
1147 			}
1148 		} else {
1149 			/*
1150 			 * Eh??  The command failed, but we don't
1151 			 * have any sense.  What's up with that?
1152 			 * Fire the CCB again to return it to the
1153 			 * caller.
1154 			 */
1155 			bcopy(done_ccb->ccb_h.saved_ccb_ptr,
1156 			      done_ccb, sizeof(union ccb));
1157 
1158 			periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1159 
1160 			xpt_action(done_ccb);
1161 
1162 		}
1163 		break;
1164 	default:
1165 		bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
1166 		      sizeof(union ccb));
1167 
1168 		periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1169 
1170 		xpt_action(done_ccb);
1171 
1172 		break;
1173 	}
1174 
1175 	/* decrement the retry count */
1176 	/*
1177 	 * XXX This isn't appropriate in all cases.  Restructure,
1178 	 *     so that the retry count is only decremented on an
1179 	 *     actual retry.  Remeber that the orignal ccb had its
1180 	 *     retry count dropped before entering recovery, so
1181 	 *     doing it again is a bug.
1182 	 */
1183 	if (done_ccb->ccb_h.retry_count > 0)
1184 		done_ccb->ccb_h.retry_count--;
1185 
1186 	qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
1187 				      /*relsim_flags*/relsim_flags,
1188 				      /*openings*/0,
1189 				      /*timeout*/timeout,
1190 				      /*getcount_only*/0);
1191 	if (xpt_done_ccb == TRUE)
1192 		(*done_ccb->ccb_h.cbfcnp)(periph, done_ccb);
1193 }
1194 
1195 /*
1196  * Generic Async Event handler.  Peripheral drivers usually
1197  * filter out the events that require personal attention,
1198  * and leave the rest to this function.
1199  */
1200 void
1201 cam_periph_async(struct cam_periph *periph, u_int32_t code,
1202 		 struct cam_path *path, void *arg)
1203 {
1204 	switch (code) {
1205 	case AC_LOST_DEVICE:
1206 		cam_periph_invalidate(periph);
1207 		break;
1208 	case AC_SENT_BDR:
1209 	case AC_BUS_RESET:
1210 	{
1211 		cam_periph_bus_settle(periph, scsi_delay);
1212 		break;
1213 	}
1214 	default:
1215 		break;
1216 	}
1217 }
1218 
1219 void
1220 cam_periph_bus_settle(struct cam_periph *periph, u_int bus_settle)
1221 {
1222 	struct ccb_getdevstats cgds;
1223 
1224 	xpt_setup_ccb(&cgds.ccb_h, periph->path, /*priority*/1);
1225 	cgds.ccb_h.func_code = XPT_GDEV_STATS;
1226 	xpt_action((union ccb *)&cgds);
1227 	cam_periph_freeze_after_event(periph, &cgds.last_reset, bus_settle);
1228 }
1229 
1230 void
1231 cam_periph_freeze_after_event(struct cam_periph *periph,
1232 			      struct timeval* event_time, u_int duration_ms)
1233 {
1234 	struct timeval delta;
1235 	struct timeval duration_tv;
1236 
1237 	microuptime(&delta);
1238 	timevalsub(&delta, event_time);
1239 	duration_tv.tv_sec = duration_ms / 1000;
1240 	duration_tv.tv_usec = (duration_ms % 1000) * 1000;
1241 	if (timevalcmp(&delta, &duration_tv, <)) {
1242 		timevalsub(&duration_tv, &delta);
1243 
1244 		duration_ms = duration_tv.tv_sec * 1000;
1245 		duration_ms += duration_tv.tv_usec / 1000;
1246 		cam_freeze_devq(periph->path);
1247 		cam_release_devq(periph->path,
1248 				RELSIM_RELEASE_AFTER_TIMEOUT,
1249 				/*reduction*/0,
1250 				/*timeout*/duration_ms,
1251 				/*getcount_only*/0);
1252 	}
1253 
1254 }
1255 
1256 static int
1257 camperiphscsistatuserror(union ccb *ccb, cam_flags camflags,
1258 			 u_int32_t sense_flags, union ccb *save_ccb,
1259 			 int *openings, u_int32_t *relsim_flags,
1260 			 u_int32_t *timeout)
1261 {
1262 	int error;
1263 
1264 	switch (ccb->csio.scsi_status) {
1265 	case SCSI_STATUS_OK:
1266 	case SCSI_STATUS_COND_MET:
1267 	case SCSI_STATUS_INTERMED:
1268 	case SCSI_STATUS_INTERMED_COND_MET:
1269 		error = 0;
1270 		break;
1271 	case SCSI_STATUS_CMD_TERMINATED:
1272 	case SCSI_STATUS_CHECK_COND:
1273 		error = camperiphscsisenseerror(ccb,
1274 					        camflags,
1275 					        sense_flags,
1276 					        save_ccb,
1277 					        openings,
1278 					        relsim_flags,
1279 					        timeout);
1280 		break;
1281 	case SCSI_STATUS_QUEUE_FULL:
1282 	{
1283 		/* no decrement */
1284 		struct ccb_getdevstats cgds;
1285 
1286 		/*
1287 		 * First off, find out what the current
1288 		 * transaction counts are.
1289 		 */
1290 		xpt_setup_ccb(&cgds.ccb_h,
1291 			      ccb->ccb_h.path,
1292 			      /*priority*/1);
1293 		cgds.ccb_h.func_code = XPT_GDEV_STATS;
1294 		xpt_action((union ccb *)&cgds);
1295 
1296 		/*
1297 		 * If we were the only transaction active, treat
1298 		 * the QUEUE FULL as if it were a BUSY condition.
1299 		 */
1300 		if (cgds.dev_active != 0) {
1301 			int total_openings;
1302 
1303 			/*
1304 			 * Reduce the number of openings to
1305 			 * be 1 less than the amount it took
1306 			 * to get a queue full bounded by the
1307 			 * minimum allowed tag count for this
1308 			 * device.
1309 			 */
1310 			total_openings = cgds.dev_active + cgds.dev_openings;
1311 			*openings = cgds.dev_active;
1312 			if (*openings < cgds.mintags)
1313 				*openings = cgds.mintags;
1314 			if (*openings < total_openings)
1315 				*relsim_flags = RELSIM_ADJUST_OPENINGS;
1316 			else {
1317 				/*
1318 				 * Some devices report queue full for
1319 				 * temporary resource shortages.  For
1320 				 * this reason, we allow a minimum
1321 				 * tag count to be entered via a
1322 				 * quirk entry to prevent the queue
1323 				 * count on these devices from falling
1324 				 * to a pessimisticly low value.  We
1325 				 * still wait for the next successful
1326 				 * completion, however, before queueing
1327 				 * more transactions to the device.
1328 				 */
1329 				*relsim_flags = RELSIM_RELEASE_AFTER_CMDCMPLT;
1330 			}
1331 			*timeout = 0;
1332 			error = ERESTART;
1333 			if (bootverbose) {
1334 				xpt_print(ccb->ccb_h.path, "Queue Full\n");
1335 			}
1336 			break;
1337 		}
1338 		/* FALLTHROUGH */
1339 	}
1340 	case SCSI_STATUS_BUSY:
1341 		/*
1342 		 * Restart the queue after either another
1343 		 * command completes or a 1 second timeout.
1344 		 */
1345 		if (bootverbose) {
1346 			xpt_print(ccb->ccb_h.path, "Device Busy\n");
1347 		}
1348 		if (ccb->ccb_h.retry_count > 0) {
1349 			ccb->ccb_h.retry_count--;
1350 			error = ERESTART;
1351 			*relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT
1352 				      | RELSIM_RELEASE_AFTER_CMDCMPLT;
1353 			*timeout = 1000;
1354 		} else {
1355 			error = EIO;
1356 		}
1357 		break;
1358 	case SCSI_STATUS_RESERV_CONFLICT:
1359 		xpt_print(ccb->ccb_h.path, "Reservation Conflict\n");
1360 		error = EIO;
1361 		break;
1362 	default:
1363 		xpt_print(ccb->ccb_h.path, "SCSI Status 0x%x\n",
1364 		    ccb->csio.scsi_status);
1365 		error = EIO;
1366 		break;
1367 	}
1368 	return (error);
1369 }
1370 
1371 static int
1372 camperiphscsisenseerror(union ccb *ccb, cam_flags camflags,
1373 			u_int32_t sense_flags, union ccb *save_ccb,
1374 		       int *openings, u_int32_t *relsim_flags,
1375 		       u_int32_t *timeout)
1376 {
1377 	struct cam_periph *periph;
1378 	int error;
1379 
1380 	periph = xpt_path_periph(ccb->ccb_h.path);
1381 	if (periph->flags & CAM_PERIPH_RECOVERY_INPROG) {
1382 
1383 		/*
1384 		 * If error recovery is already in progress, don't attempt
1385 		 * to process this error, but requeue it unconditionally
1386 		 * and attempt to process it once error recovery has
1387 		 * completed.  This failed command is probably related to
1388 		 * the error that caused the currently active error recovery
1389 		 * action so our  current recovery efforts should also
1390 		 * address this command.  Be aware that the error recovery
1391 		 * code assumes that only one recovery action is in progress
1392 		 * on a particular peripheral instance at any given time
1393 		 * (e.g. only one saved CCB for error recovery) so it is
1394 		 * imperitive that we don't violate this assumption.
1395 		 */
1396 		error = ERESTART;
1397 	} else {
1398 		scsi_sense_action err_action;
1399 		struct ccb_getdev cgd;
1400 		const char *action_string;
1401 		union ccb* print_ccb;
1402 
1403 		/* A description of the error recovery action performed */
1404 		action_string = NULL;
1405 
1406 		/*
1407 		 * The location of the orignal ccb
1408 		 * for sense printing purposes.
1409 		 */
1410 		print_ccb = ccb;
1411 
1412 		/*
1413 		 * Grab the inquiry data for this device.
1414 		 */
1415 		xpt_setup_ccb(&cgd.ccb_h, ccb->ccb_h.path, /*priority*/ 1);
1416 		cgd.ccb_h.func_code = XPT_GDEV_TYPE;
1417 		xpt_action((union ccb *)&cgd);
1418 
1419 		if ((ccb->ccb_h.status & CAM_AUTOSNS_VALID) != 0)
1420 			err_action = scsi_error_action(&ccb->csio,
1421 						       &cgd.inq_data,
1422 						       sense_flags);
1423 		else if ((ccb->ccb_h.flags & CAM_DIS_AUTOSENSE) == 0)
1424 			err_action = SS_REQSENSE;
1425 		else
1426 			err_action = SS_RETRY|SSQ_DECREMENT_COUNT|EIO;
1427 
1428 		error = err_action & SS_ERRMASK;
1429 
1430 		/*
1431 		 * If the recovery action will consume a retry,
1432 		 * make sure we actually have retries available.
1433 		 */
1434 		if ((err_action & SSQ_DECREMENT_COUNT) != 0) {
1435 			if (ccb->ccb_h.retry_count > 0)
1436 				ccb->ccb_h.retry_count--;
1437 			else {
1438 				action_string = "Retries Exhausted";
1439 				goto sense_error_done;
1440 			}
1441 		}
1442 
1443 		if ((err_action & SS_MASK) >= SS_START) {
1444 			/*
1445 			 * Do common portions of commands that
1446 			 * use recovery CCBs.
1447 			 */
1448 			if (save_ccb == NULL) {
1449 				action_string = "No recovery CCB supplied";
1450 				goto sense_error_done;
1451 			}
1452 			bcopy(ccb, save_ccb, sizeof(*save_ccb));
1453 			print_ccb = save_ccb;
1454 			periph->flags |= CAM_PERIPH_RECOVERY_INPROG;
1455 		}
1456 
1457 		switch (err_action & SS_MASK) {
1458 		case SS_NOP:
1459 			action_string = "No Recovery Action Needed";
1460 			error = 0;
1461 			break;
1462 		case SS_RETRY:
1463 			action_string = "Retrying Command (per Sense Data)";
1464 			error = ERESTART;
1465 			break;
1466 		case SS_FAIL:
1467 			action_string = "Unretryable error";
1468 			break;
1469 		case SS_START:
1470 		{
1471 			int le;
1472 
1473 			/*
1474 			 * Send a start unit command to the device, and
1475 			 * then retry the command.
1476 			 */
1477 			action_string = "Attempting to Start Unit";
1478 
1479 			/*
1480 			 * Check for removable media and set
1481 			 * load/eject flag appropriately.
1482 			 */
1483 			if (SID_IS_REMOVABLE(&cgd.inq_data))
1484 				le = TRUE;
1485 			else
1486 				le = FALSE;
1487 
1488 			scsi_start_stop(&ccb->csio,
1489 					/*retries*/1,
1490 					camperiphdone,
1491 					MSG_SIMPLE_Q_TAG,
1492 					/*start*/TRUE,
1493 					/*load/eject*/le,
1494 					/*immediate*/FALSE,
1495 					SSD_FULL_SIZE,
1496 					/*timeout*/50000);
1497 			break;
1498 		}
1499 		case SS_TUR:
1500 		{
1501 			/*
1502 			 * Send a Test Unit Ready to the device.
1503 			 * If the 'many' flag is set, we send 120
1504 			 * test unit ready commands, one every half
1505 			 * second.  Otherwise, we just send one TUR.
1506 			 * We only want to do this if the retry
1507 			 * count has not been exhausted.
1508 			 */
1509 			int retries;
1510 
1511 			if ((err_action & SSQ_MANY) != 0) {
1512 				action_string = "Polling device for readiness";
1513 				retries = 120;
1514 			} else {
1515 				action_string = "Testing device for readiness";
1516 				retries = 1;
1517 			}
1518 			scsi_test_unit_ready(&ccb->csio,
1519 					     retries,
1520 					     camperiphdone,
1521 					     MSG_SIMPLE_Q_TAG,
1522 					     SSD_FULL_SIZE,
1523 					     /*timeout*/5000);
1524 
1525 			/*
1526 			 * Accomplish our 500ms delay by deferring
1527 			 * the release of our device queue appropriately.
1528 			 */
1529 			*relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1530 			*timeout = 500;
1531 			break;
1532 		}
1533 		case SS_REQSENSE:
1534 		{
1535 			/*
1536 			 * Send a Request Sense to the device.  We
1537 			 * assume that we are in a contingent allegiance
1538 			 * condition so we do not tag this request.
1539 			 */
1540 			scsi_request_sense(&ccb->csio, /*retries*/1,
1541 					   camperiphdone,
1542 					   &save_ccb->csio.sense_data,
1543 					   sizeof(save_ccb->csio.sense_data),
1544 					   CAM_TAG_ACTION_NONE,
1545 					   /*sense_len*/SSD_FULL_SIZE,
1546 					   /*timeout*/5000);
1547 			break;
1548 		}
1549 		default:
1550 			panic("Unhandled error action %x", err_action);
1551 		}
1552 
1553 		if ((err_action & SS_MASK) >= SS_START) {
1554 			/*
1555 			 * Drop the priority to 0 so that the recovery
1556 			 * CCB is the first to execute.  Freeze the queue
1557 			 * after this command is sent so that we can
1558 			 * restore the old csio and have it queued in
1559 			 * the proper order before we release normal
1560 			 * transactions to the device.
1561 			 */
1562 			ccb->ccb_h.pinfo.priority = 0;
1563 			ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
1564 			ccb->ccb_h.saved_ccb_ptr = save_ccb;
1565 			error = ERESTART;
1566 		}
1567 
1568 sense_error_done:
1569 		if ((err_action & SSQ_PRINT_SENSE) != 0
1570 		 && (ccb->ccb_h.status & CAM_AUTOSNS_VALID) != 0) {
1571 			cam_error_print(print_ccb, CAM_ESF_ALL, CAM_EPF_ALL);
1572 			xpt_print_path(ccb->ccb_h.path);
1573 			if (bootverbose)
1574 				scsi_sense_print(&print_ccb->csio);
1575 			kprintf("%s\n", action_string);
1576 		}
1577 	}
1578 	return (error);
1579 }
1580 
1581 /*
1582  * Generic error handler.  Peripheral drivers usually filter
1583  * out the errors that they handle in a unique mannor, then
1584  * call this function.
1585  */
1586 int
1587 cam_periph_error(union ccb *ccb, cam_flags camflags,
1588 		 u_int32_t sense_flags, union ccb *save_ccb)
1589 {
1590 	const char *action_string;
1591 	cam_status  status;
1592 	int	    frozen;
1593 	int	    error, printed = 0;
1594 	int         openings;
1595 	u_int32_t   relsim_flags;
1596 	u_int32_t   timeout = 0;
1597 
1598 	action_string = NULL;
1599 	status = ccb->ccb_h.status;
1600 	frozen = (status & CAM_DEV_QFRZN) != 0;
1601 	status &= CAM_STATUS_MASK;
1602 	openings = relsim_flags = 0;
1603 
1604 	switch (status) {
1605 	case CAM_REQ_CMP:
1606 		error = 0;
1607 		break;
1608 	case CAM_SCSI_STATUS_ERROR:
1609 		error = camperiphscsistatuserror(ccb,
1610 						 camflags,
1611 						 sense_flags,
1612 						 save_ccb,
1613 						 &openings,
1614 						 &relsim_flags,
1615 						 &timeout);
1616 		break;
1617 	case CAM_AUTOSENSE_FAIL:
1618 		xpt_print(ccb->ccb_h.path, "AutoSense Failed\n");
1619 		error = EIO;	/* we have to kill the command */
1620 		break;
1621 	case CAM_REQ_CMP_ERR:
1622 		if (bootverbose && printed == 0) {
1623 			xpt_print(ccb->ccb_h.path,
1624 			    "Request completed with CAM_REQ_CMP_ERR\n");
1625 			printed++;
1626 		}
1627 		/* FALLTHROUGH */
1628 	case CAM_CMD_TIMEOUT:
1629 		if (bootverbose && printed == 0) {
1630 			xpt_print(ccb->ccb_h.path, "Command timed out\n");
1631 			printed++;
1632 		}
1633 		/* FALLTHROUGH */
1634 	case CAM_UNEXP_BUSFREE:
1635 		if (bootverbose && printed == 0) {
1636 			xpt_print(ccb->ccb_h.path, "Unexpected Bus Free\n");
1637 			printed++;
1638 		}
1639 		/* FALLTHROUGH */
1640 	case CAM_UNCOR_PARITY:
1641 		if (bootverbose && printed == 0) {
1642 			xpt_print(ccb->ccb_h.path,
1643 			    "Uncorrected Parity Error\n");
1644 			printed++;
1645 		}
1646 		/* FALLTHROUGH */
1647 	case CAM_DATA_RUN_ERR:
1648 		if (bootverbose && printed == 0) {
1649 			xpt_print(ccb->ccb_h.path, "Data Overrun\n");
1650 			printed++;
1651 		}
1652 		error = EIO;	/* we have to kill the command */
1653 		/* decrement the number of retries */
1654 		if (ccb->ccb_h.retry_count > 0) {
1655 			ccb->ccb_h.retry_count--;
1656 			error = ERESTART;
1657 		} else {
1658 			action_string = "Retries Exhausted";
1659 			error = EIO;
1660 		}
1661 		break;
1662 	case CAM_UA_ABORT:
1663 	case CAM_UA_TERMIO:
1664 	case CAM_MSG_REJECT_REC:
1665 		/* XXX Don't know that these are correct */
1666 		error = EIO;
1667 		break;
1668 	case CAM_SEL_TIMEOUT:
1669 	{
1670 		struct cam_path *newpath;
1671 
1672 		if ((camflags & CAM_RETRY_SELTO) != 0) {
1673 			if (ccb->ccb_h.retry_count > 0) {
1674 
1675 				ccb->ccb_h.retry_count--;
1676 				error = ERESTART;
1677 				if (bootverbose && printed == 0) {
1678 					xpt_print(ccb->ccb_h.path,
1679 					    "Selection Timeout\n");
1680 					printed++;
1681 				}
1682 
1683 				/*
1684 				 * Wait a bit to give the device
1685 				 * time to recover before we try again.
1686 				 */
1687 				relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1688 				timeout = periph_selto_delay;
1689 				break;
1690 			}
1691 		}
1692 		error = ENXIO;
1693 		/* Should we do more if we can't create the path?? */
1694 		if (xpt_create_path(&newpath, xpt_path_periph(ccb->ccb_h.path),
1695 				    xpt_path_path_id(ccb->ccb_h.path),
1696 				    xpt_path_target_id(ccb->ccb_h.path),
1697 				    CAM_LUN_WILDCARD) != CAM_REQ_CMP)
1698 			break;
1699 
1700 		/*
1701 		 * Let peripheral drivers know that this device has gone
1702 		 * away.
1703 		 */
1704 		xpt_async(AC_LOST_DEVICE, newpath, NULL);
1705 		xpt_free_path(newpath);
1706 		break;
1707 	}
1708 	case CAM_REQ_INVALID:
1709 	case CAM_PATH_INVALID:
1710 	case CAM_DEV_NOT_THERE:
1711 	case CAM_NO_HBA:
1712 	case CAM_PROVIDE_FAIL:
1713 	case CAM_REQ_TOO_BIG:
1714 	case CAM_LUN_INVALID:
1715 	case CAM_TID_INVALID:
1716 		error = EINVAL;
1717 		break;
1718 	case CAM_SCSI_BUS_RESET:
1719 	case CAM_BDR_SENT:
1720 		/*
1721 		 * Commands that repeatedly timeout and cause these
1722 		 * kinds of error recovery actions, should return
1723 		 * CAM_CMD_TIMEOUT, which allows us to safely assume
1724 		 * that this command was an innocent bystander to
1725 		 * these events and should be unconditionally
1726 		 * retried.
1727 		 */
1728 		if (bootverbose && printed == 0) {
1729 			xpt_print_path(ccb->ccb_h.path);
1730 			if (status == CAM_BDR_SENT)
1731 				kprintf("Bus Device Reset sent\n");
1732 			else
1733 				kprintf("Bus Reset issued\n");
1734 			printed++;
1735 		}
1736 		/* FALLTHROUGH */
1737 	case CAM_REQUEUE_REQ:
1738 		/* Unconditional requeue */
1739 		error = ERESTART;
1740 		if (bootverbose && printed == 0) {
1741 			xpt_print(ccb->ccb_h.path, "Request Requeued\n");
1742 			printed++;
1743 		}
1744 		break;
1745 	case CAM_RESRC_UNAVAIL:
1746 		/* Wait a bit for the resource shortage to abate. */
1747 		timeout = periph_noresrc_delay;
1748 		/* FALLTHROUGH */
1749 	case CAM_BUSY:
1750 		if (timeout == 0) {
1751 			/* Wait a bit for the busy condition to abate. */
1752 			timeout = periph_busy_delay;
1753 		}
1754 		relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1755 		/* FALLTHROUGH */
1756 	default:
1757 		/* decrement the number of retries */
1758 		if (ccb->ccb_h.retry_count > 0) {
1759 			ccb->ccb_h.retry_count--;
1760 			error = ERESTART;
1761 			if (bootverbose && printed == 0) {
1762 				xpt_print(ccb->ccb_h.path, "CAM Status 0x%x\n",
1763 				    status);
1764 				printed++;
1765 			}
1766 		} else {
1767 			error = EIO;
1768 			action_string = "Retries Exhausted";
1769 		}
1770 		break;
1771 	}
1772 
1773 	/* Attempt a retry */
1774 	if (error == ERESTART || error == 0) {
1775 		if (frozen != 0)
1776 			ccb->ccb_h.status &= ~CAM_DEV_QFRZN;
1777 
1778 		if (error == ERESTART) {
1779 			action_string = "Retrying Command";
1780 			xpt_action(ccb);
1781 		}
1782 
1783 		if (frozen != 0)
1784 			cam_release_devq(ccb->ccb_h.path,
1785 					 relsim_flags,
1786 					 openings,
1787 					 timeout,
1788 					 /*getcount_only*/0);
1789 	}
1790 
1791 	/*
1792 	 * If we have an error and are booting verbosely, whine
1793 	 * *unless* this was a non-retryable selection timeout.
1794 	 */
1795 	if (error != 0 && bootverbose && (sense_flags & SF_NO_PRINT) == 0 &&
1796 	    !(status == CAM_SEL_TIMEOUT && (camflags & CAM_RETRY_SELTO) == 0)) {
1797 
1798 
1799 		if (action_string == NULL)
1800 			action_string = "Unretryable Error";
1801 		if (error != ERESTART) {
1802 			xpt_print(ccb->ccb_h.path, "error %d\n", error);
1803 		}
1804 		xpt_print(ccb->ccb_h.path, "%s\n", action_string);
1805 	}
1806 
1807 	return (error);
1808 }
1809