xref: /freebsd/sys/cam/scsi/scsi_enc.c (revision d7d962ead0b6e5e8a39202d0590022082bf5bfb6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2000 Matthew Jacob
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification, immediately at the beginning of the file.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 
34 #include <sys/conf.h>
35 #include <sys/errno.h>
36 #include <sys/fcntl.h>
37 #include <sys/kernel.h>
38 #include <sys/kthread.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/mutex.h>
42 #include <sys/proc.h>
43 #include <sys/queue.h>
44 #include <sys/sbuf.h>
45 #include <sys/sx.h>
46 #include <sys/sysent.h>
47 #include <sys/systm.h>
48 #include <sys/sysctl.h>
49 #include <sys/types.h>
50 
51 #include <machine/stdarg.h>
52 
53 #include <cam/cam.h>
54 #include <cam/cam_ccb.h>
55 #include <cam/cam_debug.h>
56 #include <cam/cam_periph.h>
57 #include <cam/cam_xpt_periph.h>
58 
59 #include <cam/scsi/scsi_all.h>
60 #include <cam/scsi/scsi_message.h>
61 #include <cam/scsi/scsi_enc.h>
62 #include <cam/scsi/scsi_enc_internal.h>
63 
64 #include "opt_ses.h"
65 
66 MALLOC_DEFINE(M_SCSIENC, "SCSI ENC", "SCSI ENC buffers");
67 
68 /* Enclosure type independent driver */
69 
70 static	d_open_t	enc_open;
71 static	d_close_t	enc_close;
72 static	d_ioctl_t	enc_ioctl;
73 static	periph_init_t	enc_init;
74 static  periph_ctor_t	enc_ctor;
75 static	periph_oninv_t	enc_oninvalidate;
76 static  periph_dtor_t   enc_dtor;
77 
78 static void enc_async(void *, uint32_t, struct cam_path *, void *);
79 static enctyp enc_type(struct ccb_getdev *);
80 
81 SYSCTL_NODE(_kern_cam, OID_AUTO, enc, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
82     "CAM Enclosure Services driver");
83 
84 #if defined(DEBUG) || defined(ENC_DEBUG)
85 int enc_verbose = 1;
86 #else
87 int enc_verbose = 0;
88 #endif
89 SYSCTL_INT(_kern_cam_enc, OID_AUTO, verbose, CTLFLAG_RWTUN,
90            &enc_verbose, 0, "Enable verbose logging");
91 
92 const char *elm_type_names[] = ELM_TYPE_NAMES;
93 CTASSERT(nitems(elm_type_names) - 1 == ELMTYP_LAST);
94 
95 static struct periph_driver encdriver = {
96 	enc_init, "ses",
97 	TAILQ_HEAD_INITIALIZER(encdriver.units), /* generation */ 0
98 };
99 
100 PERIPHDRIVER_DECLARE(enc, encdriver);
101 
102 static struct cdevsw enc_cdevsw = {
103 	.d_version =	D_VERSION,
104 	.d_open =	enc_open,
105 	.d_close =	enc_close,
106 	.d_ioctl =	enc_ioctl,
107 	.d_name =	"ses",
108 	.d_flags =	D_TRACKCLOSE,
109 };
110 
111 static void
112 enc_init(void)
113 {
114 	cam_status status;
115 
116 	/*
117 	 * Install a global async callback.  This callback will
118 	 * receive async callbacks like "new device found".
119 	 */
120 	status = xpt_register_async(AC_FOUND_DEVICE, enc_async, NULL, NULL);
121 
122 	if (status != CAM_REQ_CMP) {
123 		printf("enc: Failed to attach master async callback "
124 		       "due to status 0x%x!\n", status);
125 	}
126 }
127 
128 static void
129 enc_devgonecb(void *arg)
130 {
131 	struct cam_periph *periph;
132 	struct enc_softc  *enc;
133 	struct mtx *mtx;
134 	int i;
135 
136 	periph = (struct cam_periph *)arg;
137 	mtx = cam_periph_mtx(periph);
138 	mtx_lock(mtx);
139 	enc = (struct enc_softc *)periph->softc;
140 
141 	/*
142 	 * When we get this callback, we will get no more close calls from
143 	 * devfs.  So if we have any dangling opens, we need to release the
144 	 * reference held for that particular context.
145 	 */
146 	for (i = 0; i < enc->open_count; i++)
147 		cam_periph_release_locked(periph);
148 
149 	enc->open_count = 0;
150 
151 	/*
152 	 * Release the reference held for the device node, it is gone now.
153 	 */
154 	cam_periph_release_locked(periph);
155 
156 	/*
157 	 * We reference the lock directly here, instead of using
158 	 * cam_periph_unlock().  The reason is that the final call to
159 	 * cam_periph_release_locked() above could result in the periph
160 	 * getting freed.  If that is the case, dereferencing the periph
161 	 * with a cam_periph_unlock() call would cause a page fault.
162 	 */
163 	mtx_unlock(mtx);
164 }
165 
166 static void
167 enc_oninvalidate(struct cam_periph *periph)
168 {
169 	struct enc_softc *enc;
170 
171 	enc = periph->softc;
172 
173 	enc->enc_flags |= ENC_FLAG_INVALID;
174 
175 	/* If the sub-driver has an invalidate routine, call it */
176 	if (enc->enc_vec.softc_invalidate != NULL)
177 		enc->enc_vec.softc_invalidate(enc);
178 
179 	/*
180 	 * Unregister any async callbacks.
181 	 */
182 	xpt_register_async(0, enc_async, periph, periph->path);
183 
184 	/*
185 	 * Shutdown our daemon.
186 	 */
187 	enc->enc_flags |= ENC_FLAG_SHUTDOWN;
188 	if (enc->enc_daemon != NULL) {
189 		/* Signal the ses daemon to terminate. */
190 		wakeup(enc->enc_daemon);
191 	}
192 	callout_drain(&enc->status_updater);
193 
194 	destroy_dev_sched_cb(enc->enc_dev, enc_devgonecb, periph);
195 }
196 
197 static void
198 enc_dtor(struct cam_periph *periph)
199 {
200 	struct enc_softc *enc;
201 
202 	enc = periph->softc;
203 
204 	/* If the sub-driver has a cleanup routine, call it */
205 	if (enc->enc_vec.softc_cleanup != NULL)
206 		enc->enc_vec.softc_cleanup(enc);
207 
208 	root_mount_rel(&enc->enc_rootmount);
209 
210 	ENC_FREE(enc);
211 }
212 
213 static void
214 enc_async(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
215 {
216 	struct cam_periph *periph;
217 
218 	periph = (struct cam_periph *)callback_arg;
219 
220 	switch(code) {
221 	case AC_FOUND_DEVICE:
222 	{
223 		struct ccb_getdev *cgd;
224 		cam_status status;
225 		path_id_t path_id;
226 
227 		cgd = (struct ccb_getdev *)arg;
228 		if (arg == NULL) {
229 			break;
230 		}
231 
232 		if (enc_type(cgd) == ENC_NONE) {
233 			/*
234 			 * Schedule announcement of the ENC bindings for
235 			 * this device if it is managed by a SEP.
236 			 */
237 			path_id = xpt_path_path_id(path);
238 			xpt_lock_buses();
239 			TAILQ_FOREACH(periph, &encdriver.units, unit_links) {
240 				struct enc_softc *softc;
241 
242 				softc = (struct enc_softc *)periph->softc;
243 
244 				/* Check this SEP is ready. */
245 				if (softc == NULL || (softc->enc_flags &
246 				     ENC_FLAG_INITIALIZED) == 0 ||
247 				    softc->enc_vec.device_found == NULL)
248 					continue;
249 
250 				/* Check this SEP may manage this device. */
251 				if (xpt_path_path_id(periph->path) != path_id &&
252 				    (softc->enc_type != ENC_SEMB_SES ||
253 				     cgd->protocol != PROTO_ATA))
254 					continue;
255 
256 				softc->enc_vec.device_found(softc);
257 			}
258 			xpt_unlock_buses();
259 			return;
260 		}
261 
262 		status = cam_periph_alloc(enc_ctor, enc_oninvalidate,
263 		    enc_dtor, NULL, "ses", CAM_PERIPH_BIO,
264 		    path, enc_async, AC_FOUND_DEVICE, cgd);
265 
266 		if (status != CAM_REQ_CMP && status != CAM_REQ_INPROG) {
267 			printf("enc_async: Unable to probe new device due to "
268 			    "status 0x%x\n", status);
269 		}
270 		break;
271 	}
272 	default:
273 		cam_periph_async(periph, code, path, arg);
274 		break;
275 	}
276 }
277 
278 static int
279 enc_open(struct cdev *dev, int flags, int fmt, struct thread *td)
280 {
281 	struct cam_periph *periph;
282 	struct enc_softc *softc;
283 	int error = 0;
284 
285 	periph = (struct cam_periph *)dev->si_drv1;
286 	if (cam_periph_acquire(periph) != 0)
287 		return (ENXIO);
288 
289 	cam_periph_lock(periph);
290 
291 	softc = (struct enc_softc *)periph->softc;
292 
293 	if ((softc->enc_flags & ENC_FLAG_INITIALIZED) == 0) {
294 		error = ENXIO;
295 		goto out;
296 	}
297 	if (softc->enc_flags & ENC_FLAG_INVALID) {
298 		error = ENXIO;
299 		goto out;
300 	}
301 out:
302 	if (error != 0)
303 		cam_periph_release_locked(periph);
304 	else
305 		softc->open_count++;
306 
307 	cam_periph_unlock(periph);
308 
309 	return (error);
310 }
311 
312 static int
313 enc_close(struct cdev *dev, int flag, int fmt, struct thread *td)
314 {
315 	struct cam_periph *periph;
316 	struct enc_softc  *enc;
317 	struct mtx *mtx;
318 
319 	periph = (struct cam_periph *)dev->si_drv1;
320 	mtx = cam_periph_mtx(periph);
321 	mtx_lock(mtx);
322 
323 	enc = periph->softc;
324 	enc->open_count--;
325 
326 	cam_periph_release_locked(periph);
327 
328 	/*
329 	 * We reference the lock directly here, instead of using
330 	 * cam_periph_unlock().  The reason is that the call to
331 	 * cam_periph_release_locked() above could result in the periph
332 	 * getting freed.  If that is the case, dereferencing the periph
333 	 * with a cam_periph_unlock() call would cause a page fault.
334 	 *
335 	 * cam_periph_release() avoids this problem using the same method,
336 	 * but we're manually acquiring and dropping the lock here to
337 	 * protect the open count and avoid another lock acquisition and
338 	 * release.
339 	 */
340 	mtx_unlock(mtx);
341 
342 	return (0);
343 }
344 
345 int
346 enc_error(union ccb *ccb, uint32_t cflags, uint32_t sflags)
347 {
348 	struct enc_softc *softc;
349 	struct cam_periph *periph;
350 
351 	periph = xpt_path_periph(ccb->ccb_h.path);
352 	softc = (struct enc_softc *)periph->softc;
353 
354 	return (cam_periph_error(ccb, cflags, sflags));
355 }
356 
357 static int
358 enc_ioctl(struct cdev *dev, u_long cmd, caddr_t arg_addr, int flag,
359 	 struct thread *td)
360 {
361 	struct cam_periph *periph;
362 	encioc_enc_status_t tmp;
363 	encioc_string_t sstr;
364 	encioc_elm_status_t elms;
365 	encioc_elm_desc_t elmd;
366 	encioc_elm_devnames_t elmdn;
367 	encioc_element_t *uelm;
368 	enc_softc_t *enc;
369 	enc_cache_t *cache;
370 	void *addr;
371 	int error, i;
372 
373 #ifdef	COMPAT_FREEBSD32
374 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32))
375 		return (ENOTTY);
376 #endif
377 
378 	if (arg_addr)
379 		addr = *((caddr_t *) arg_addr);
380 	else
381 		addr = NULL;
382 
383 	periph = (struct cam_periph *)dev->si_drv1;
384 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering encioctl\n"));
385 
386 	cam_periph_lock(periph);
387 	enc = (struct enc_softc *)periph->softc;
388 	cache = &enc->enc_cache;
389 
390 	/*
391 	 * Now check to see whether we're initialized or not.
392 	 * This actually should never fail as we're not supposed
393 	 * to get past enc_open w/o successfully initializing
394 	 * things.
395 	 */
396 	if ((enc->enc_flags & ENC_FLAG_INITIALIZED) == 0) {
397 		cam_periph_unlock(periph);
398 		return (ENXIO);
399 	}
400 	cam_periph_unlock(periph);
401 
402 	error = 0;
403 
404 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE,
405 	    ("trying to do ioctl %#lx\n", cmd));
406 
407 	/*
408 	 * If this command can change the device's state,
409 	 * we must have the device open for writing.
410 	 *
411 	 * For commands that get information about the
412 	 * device- we don't need to lock the peripheral
413 	 * if we aren't running a command.  The periph
414 	 * also can't go away while a user process has
415 	 * it open.
416 	 */
417 	switch (cmd) {
418 	case ENCIOC_GETNELM:
419 	case ENCIOC_GETELMMAP:
420 	case ENCIOC_GETENCSTAT:
421 	case ENCIOC_GETELMSTAT:
422 	case ENCIOC_GETELMDESC:
423 	case ENCIOC_GETELMDEVNAMES:
424 	case ENCIOC_GETENCNAME:
425 	case ENCIOC_GETENCID:
426 		break;
427 	default:
428 		if ((flag & FWRITE) == 0) {
429 			return (EBADF);
430 		}
431 	}
432 
433 	/*
434 	 * XXX The values read here are only valid for the current
435 	 *     configuration generation.  We need these ioctls
436 	 *     to also pass in/out a generation number.
437 	 */
438 	sx_slock(&enc->enc_cache_lock);
439 	switch (cmd) {
440 	case ENCIOC_GETNELM:
441 		error = copyout(&cache->nelms, addr, sizeof (cache->nelms));
442 		break;
443 
444 	case ENCIOC_GETELMMAP:
445 		for (uelm = addr, i = 0; i != cache->nelms; i++) {
446 			encioc_element_t kelm;
447 			kelm.elm_idx = i;
448 			kelm.elm_subenc_id = cache->elm_map[i].subenclosure;
449 			kelm.elm_type = cache->elm_map[i].elm_type;
450 			error = copyout(&kelm, &uelm[i], sizeof(kelm));
451 			if (error)
452 				break;
453 		}
454 		break;
455 
456 	case ENCIOC_GETENCSTAT:
457 		cam_periph_lock(periph);
458 		error = enc->enc_vec.get_enc_status(enc, 1);
459 		if (error) {
460 			cam_periph_unlock(periph);
461 			break;
462 		}
463 		tmp = cache->enc_status;
464 		cam_periph_unlock(periph);
465 		error = copyout(&tmp, addr, sizeof(tmp));
466 		cache->enc_status = tmp;
467 		break;
468 
469 	case ENCIOC_SETENCSTAT:
470 		error = copyin(addr, &tmp, sizeof(tmp));
471 		if (error)
472 			break;
473 		cam_periph_lock(periph);
474 		error = enc->enc_vec.set_enc_status(enc, tmp, 1);
475 		cam_periph_unlock(periph);
476 		break;
477 
478 	case ENCIOC_GETSTRING:
479 	case ENCIOC_SETSTRING:
480 	case ENCIOC_GETENCNAME:
481 	case ENCIOC_GETENCID:
482 		if (enc->enc_vec.handle_string == NULL) {
483 			error = EINVAL;
484 			break;
485 		}
486 		error = copyin(addr, &sstr, sizeof(sstr));
487 		if (error)
488 			break;
489 		cam_periph_lock(periph);
490 		error = enc->enc_vec.handle_string(enc, &sstr, cmd);
491 		cam_periph_unlock(periph);
492 		if (error == 0 || error == ENOMEM)
493 			(void)copyout(&sstr.bufsiz,
494 			    &((encioc_string_t *)addr)->bufsiz,
495 			    sizeof(sstr.bufsiz));
496 		break;
497 
498 	case ENCIOC_GETELMSTAT:
499 		error = copyin(addr, &elms, sizeof(elms));
500 		if (error)
501 			break;
502 		if (elms.elm_idx >= cache->nelms) {
503 			error = EINVAL;
504 			break;
505 		}
506 		cam_periph_lock(periph);
507 		error = enc->enc_vec.get_elm_status(enc, &elms, 1);
508 		cam_periph_unlock(periph);
509 		if (error)
510 			break;
511 		error = copyout(&elms, addr, sizeof(elms));
512 		break;
513 
514 	case ENCIOC_GETELMDESC:
515 		error = copyin(addr, &elmd, sizeof(elmd));
516 		if (error)
517 			break;
518 		if (elmd.elm_idx >= cache->nelms) {
519 			error = EINVAL;
520 			break;
521 		}
522 		if (enc->enc_vec.get_elm_desc != NULL) {
523 			error = enc->enc_vec.get_elm_desc(enc, &elmd);
524 			if (error)
525 				break;
526 		} else
527 			elmd.elm_desc_len = 0;
528 		error = copyout(&elmd, addr, sizeof(elmd));
529 		break;
530 
531 	case ENCIOC_GETELMDEVNAMES:
532 		if (enc->enc_vec.get_elm_devnames == NULL) {
533 			error = EINVAL;
534 			break;
535 		}
536 		error = copyin(addr, &elmdn, sizeof(elmdn));
537 		if (error)
538 			break;
539 		if (elmdn.elm_idx >= cache->nelms) {
540 			error = EINVAL;
541 			break;
542 		}
543 		cam_periph_lock(periph);
544 		error = (*enc->enc_vec.get_elm_devnames)(enc, &elmdn);
545 		cam_periph_unlock(periph);
546 		if (error)
547 			break;
548 		error = copyout(&elmdn, addr, sizeof(elmdn));
549 		break;
550 
551 	case ENCIOC_SETELMSTAT:
552 		error = copyin(addr, &elms, sizeof(elms));
553 		if (error)
554 			break;
555 
556 		if (elms.elm_idx >= cache->nelms) {
557 			error = EINVAL;
558 			break;
559 		}
560 		cam_periph_lock(periph);
561 		error = enc->enc_vec.set_elm_status(enc, &elms, 1);
562 		cam_periph_unlock(periph);
563 
564 		break;
565 
566 	case ENCIOC_INIT:
567 
568 		cam_periph_lock(periph);
569 		error = enc->enc_vec.init_enc(enc);
570 		cam_periph_unlock(periph);
571 		break;
572 
573 	default:
574 		cam_periph_lock(periph);
575 		error = cam_periph_ioctl(periph, cmd, arg_addr, enc_error);
576 		cam_periph_unlock(periph);
577 		break;
578 	}
579 	sx_sunlock(&enc->enc_cache_lock);
580 	return (error);
581 }
582 
583 int
584 enc_runcmd(struct enc_softc *enc, char *cdb, int cdbl, char *dptr, int *dlenp)
585 {
586 	int error, dlen, tdlen;
587 	ccb_flags ddf;
588 	union ccb *ccb;
589 
590 	CAM_DEBUG(enc->periph->path, CAM_DEBUG_TRACE,
591 	    ("entering enc_runcmd\n"));
592 	if (dptr) {
593 		if ((dlen = *dlenp) < 0) {
594 			dlen = -dlen;
595 			ddf = CAM_DIR_OUT;
596 		} else {
597 			ddf = CAM_DIR_IN;
598 		}
599 	} else {
600 		dlen = 0;
601 		ddf = CAM_DIR_NONE;
602 	}
603 
604 	if (cdbl > IOCDBLEN) {
605 		cdbl = IOCDBLEN;
606 	}
607 
608 	ccb = cam_periph_getccb(enc->periph, CAM_PRIORITY_NORMAL);
609 	if (enc->enc_type == ENC_SEMB_SES || enc->enc_type == ENC_SEMB_SAFT) {
610 		tdlen = min(dlen, 1020);
611 		tdlen = (tdlen + 3) & ~3;
612 		cam_fill_ataio(&ccb->ataio, 0, NULL, ddf, 0, dptr, tdlen,
613 		    30 * 1000);
614 		if (cdb[0] == RECEIVE_DIAGNOSTIC)
615 			ata_28bit_cmd(&ccb->ataio,
616 			    ATA_SEP_ATTN, cdb[2], 0x02, tdlen / 4);
617 		else if (cdb[0] == SEND_DIAGNOSTIC)
618 			ata_28bit_cmd(&ccb->ataio,
619 			    ATA_SEP_ATTN, dlen > 0 ? dptr[0] : 0,
620 			    0x82, tdlen / 4);
621 		else if (cdb[0] == READ_BUFFER)
622 			ata_28bit_cmd(&ccb->ataio,
623 			    ATA_SEP_ATTN, cdb[2], 0x00, tdlen / 4);
624 		else
625 			ata_28bit_cmd(&ccb->ataio,
626 			    ATA_SEP_ATTN, dlen > 0 ? dptr[0] : 0,
627 			    0x80, tdlen / 4);
628 	} else {
629 		tdlen = dlen;
630 		cam_fill_csio(&ccb->csio, 0, NULL, ddf, MSG_SIMPLE_Q_TAG,
631 		    dptr, dlen, sizeof (struct scsi_sense_data), cdbl,
632 		    60 * 1000);
633 		bcopy(cdb, ccb->csio.cdb_io.cdb_bytes, cdbl);
634 	}
635 
636 	error = cam_periph_runccb(ccb, enc_error, ENC_CFLAGS, ENC_FLAGS, NULL);
637 	if (error) {
638 		if (dptr) {
639 			*dlenp = dlen;
640 		}
641 	} else {
642 		if (dptr) {
643 			if (ccb->ccb_h.func_code == XPT_ATA_IO)
644 				*dlenp = ccb->ataio.resid;
645 			else
646 				*dlenp = ccb->csio.resid;
647 			*dlenp += tdlen - dlen;
648 		}
649 	}
650 	xpt_release_ccb(ccb);
651 	CAM_DEBUG(enc->periph->path, CAM_DEBUG_SUBTRACE,
652 	    ("exiting enc_runcmd: *dlenp = %d\n", *dlenp));
653 	return (error);
654 }
655 
656 void
657 enc_log(struct enc_softc *enc, const char *fmt, ...)
658 {
659 	va_list ap;
660 
661 	printf("%s%d: ", enc->periph->periph_name, enc->periph->unit_number);
662 	va_start(ap, fmt);
663 	vprintf(fmt, ap);
664 	va_end(ap);
665 }
666 
667 /*
668  * The code after this point runs on many platforms,
669  * so forgive the slightly awkward and nonconforming
670  * appearance.
671  */
672 
673 /*
674  * Is this a device that supports enclosure services?
675  *
676  * It's a pretty simple ruleset- if it is device type
677  * 0x0D (13), it's an ENCLOSURE device.
678  */
679 
680 #define	SAFTE_START	44
681 #define	SAFTE_END	50
682 #define	SAFTE_LEN	SAFTE_END-SAFTE_START
683 
684 static enctyp
685 enc_type(struct ccb_getdev *cgd)
686 {
687 	int buflen;
688 	unsigned char *iqd;
689 
690 	if (cgd->protocol == PROTO_SEMB) {
691 		iqd = (unsigned char *)&cgd->ident_data;
692 		if (STRNCMP(iqd + 43, "S-E-S", 5) == 0)
693 			return (ENC_SEMB_SES);
694 		else if (STRNCMP(iqd + 43, "SAF-TE", 6) == 0)
695 			return (ENC_SEMB_SAFT);
696 		return (ENC_NONE);
697 
698 	} else if (cgd->protocol != PROTO_SCSI)
699 		return (ENC_NONE);
700 
701 	iqd = (unsigned char *)&cgd->inq_data;
702 	buflen = min(sizeof(cgd->inq_data),
703 	    SID_ADDITIONAL_LENGTH(&cgd->inq_data));
704 
705 	if ((iqd[0] & 0x1f) == T_ENCLOSURE)
706 		return (ENC_SES);
707 
708 #ifdef	SES_ENABLE_PASSTHROUGH
709 	if ((iqd[6] & 0x40) && (iqd[2] & 0x7) >= 2) {
710 		/*
711 		 * PassThrough Device.
712 		 */
713 		return (ENC_SES_PASSTHROUGH);
714 	}
715 #endif
716 
717 	/*
718 	 * The comparison is short for a reason-
719 	 * some vendors were chopping it short.
720 	 */
721 
722 	if (buflen < SAFTE_END - 2) {
723 		return (ENC_NONE);
724 	}
725 
726 	if (STRNCMP((char *)&iqd[SAFTE_START], "SAF-TE", SAFTE_LEN - 2) == 0) {
727 		return (ENC_SAFT);
728 	}
729 	return (ENC_NONE);
730 }
731 
732 /*================== Enclosure Monitoring/Processing Daemon ==================*/
733 /**
734  * \brief Queue an update request for a given action, if needed.
735  *
736  * \param enc		SES softc to queue the request for.
737  * \param action	Action requested.
738  */
739 void
740 enc_update_request(enc_softc_t *enc, uint32_t action)
741 {
742 	if ((enc->pending_actions & (0x1 << action)) == 0) {
743 		enc->pending_actions |= (0x1 << action);
744 		ENC_DLOG(enc, "%s: queing requested action %d\n",
745 		    __func__, action);
746 		if (enc->current_action == ENC_UPDATE_NONE)
747 			wakeup(enc->enc_daemon);
748 	} else {
749 		ENC_DLOG(enc, "%s: ignoring requested action %d - "
750 		    "Already queued\n", __func__, action);
751 	}
752 }
753 
754 /**
755  * \brief Invoke the handler of the highest priority pending
756  *	  state in the SES state machine.
757  *
758  * \param enc  The SES instance invoking the state machine.
759  */
760 static void
761 enc_fsm_step(enc_softc_t *enc)
762 {
763 	union ccb            *ccb;
764 	uint8_t              *buf;
765 	struct enc_fsm_state *cur_state;
766 	int		      error;
767 	uint32_t	      xfer_len;
768 
769 	ENC_DLOG(enc, "%s enter %p\n", __func__, enc);
770 
771 	enc->current_action   = ffs(enc->pending_actions) - 1;
772 	enc->pending_actions &= ~(0x1 << enc->current_action);
773 
774 	cur_state = &enc->enc_fsm_states[enc->current_action];
775 
776 	buf = NULL;
777 	if (cur_state->buf_size != 0) {
778 		cam_periph_unlock(enc->periph);
779 		buf = malloc(cur_state->buf_size, M_SCSIENC, M_WAITOK|M_ZERO);
780 		cam_periph_lock(enc->periph);
781 	}
782 
783 	error = 0;
784 	ccb   = NULL;
785 	if (cur_state->fill != NULL) {
786 		ccb = cam_periph_getccb(enc->periph, CAM_PRIORITY_NORMAL);
787 
788 		error = cur_state->fill(enc, cur_state, ccb, buf);
789 		if (error != 0)
790 			goto done;
791 
792 		error = cam_periph_runccb(ccb, cur_state->error,
793 					  ENC_CFLAGS,
794 					  ENC_FLAGS|SF_QUIET_IR, NULL);
795 	}
796 
797 	if (ccb != NULL) {
798 		if (ccb->ccb_h.func_code == XPT_ATA_IO)
799 			xfer_len = ccb->ataio.dxfer_len - ccb->ataio.resid;
800 		else
801 			xfer_len = ccb->csio.dxfer_len - ccb->csio.resid;
802 	} else
803 		xfer_len = 0;
804 
805 	cam_periph_unlock(enc->periph);
806 	cur_state->done(enc, cur_state, ccb, &buf, error, xfer_len);
807 	cam_periph_lock(enc->periph);
808 
809 done:
810 	ENC_DLOG(enc, "%s exit - result %d\n", __func__, error);
811 	ENC_FREE_AND_NULL(buf);
812 	if (ccb != NULL)
813 		xpt_release_ccb(ccb);
814 }
815 
816 /**
817  * \invariant Called with cam_periph mutex held.
818  */
819 static void
820 enc_status_updater(void *arg)
821 {
822 	enc_softc_t *enc;
823 
824 	enc = arg;
825 	if (enc->enc_vec.poll_status != NULL)
826 		enc->enc_vec.poll_status(enc);
827 }
828 
829 static void
830 enc_daemon(void *arg)
831 {
832 	enc_softc_t *enc;
833 
834 	enc = arg;
835 
836 	cam_periph_lock(enc->periph);
837 	while ((enc->enc_flags & ENC_FLAG_SHUTDOWN) == 0) {
838 		if (enc->pending_actions == 0) {
839 			/*
840 			 * Reset callout and msleep, or
841 			 * issue timed task completion
842 			 * status command.
843 			 */
844 			enc->current_action = ENC_UPDATE_NONE;
845 
846 			/*
847 			 * We've been through our state machine at least
848 			 * once.  Allow the transition to userland.
849 			 */
850 			root_mount_rel(&enc->enc_rootmount);
851 
852 			callout_reset(&enc->status_updater, 60*hz,
853 				      enc_status_updater, enc);
854 
855 			cam_periph_sleep(enc->periph, enc->enc_daemon,
856 					 PUSER, "idle", 0);
857 		} else {
858 			enc_fsm_step(enc);
859 		}
860 	}
861 	enc->enc_daemon = NULL;
862 	cam_periph_unlock(enc->periph);
863 	cam_periph_release(enc->periph);
864 	kproc_exit(0);
865 }
866 
867 static int
868 enc_kproc_init(enc_softc_t *enc)
869 {
870 	int result;
871 
872 	callout_init_mtx(&enc->status_updater, cam_periph_mtx(enc->periph), 0);
873 
874 	if (cam_periph_acquire(enc->periph) != 0)
875 		return (ENXIO);
876 
877 	result = kproc_create(enc_daemon, enc, &enc->enc_daemon, /*flags*/0,
878 			      /*stackpgs*/0, "enc_daemon%d",
879 			      enc->periph->unit_number);
880 	if (result == 0) {
881 		/* Do an initial load of all page data. */
882 		cam_periph_lock(enc->periph);
883 		enc->enc_vec.poll_status(enc);
884 		cam_periph_unlock(enc->periph);
885 	} else
886 		cam_periph_release(enc->periph);
887 	return (result);
888 }
889 
890 static cam_status
891 enc_ctor(struct cam_periph *periph, void *arg)
892 {
893 	cam_status status = CAM_REQ_CMP_ERR;
894 	int err;
895 	enc_softc_t *enc;
896 	struct ccb_getdev *cgd;
897 	char *tname;
898 	struct make_dev_args args;
899 	struct sbuf sb;
900 
901 	cgd = (struct ccb_getdev *)arg;
902 	if (cgd == NULL) {
903 		printf("enc_ctor: no getdev CCB, can't register device\n");
904 		goto out;
905 	}
906 
907 	enc = ENC_MALLOCZ(sizeof(*enc));
908 	if (enc == NULL) {
909 		printf("enc_ctor: Unable to probe new device. "
910 		       "Unable to allocate enc\n");
911 		goto out;
912 	}
913 	enc->periph = periph;
914 	enc->current_action = ENC_UPDATE_INVALID;
915 
916 	enc->enc_type = enc_type(cgd);
917 	sx_init(&enc->enc_cache_lock, "enccache");
918 
919 	switch (enc->enc_type) {
920 	case ENC_SES:
921 	case ENC_SES_PASSTHROUGH:
922 	case ENC_SEMB_SES:
923 		err = ses_softc_init(enc);
924 		break;
925 	case ENC_SAFT:
926 	case ENC_SEMB_SAFT:
927 		err = safte_softc_init(enc);
928 		break;
929 	case ENC_NONE:
930 	default:
931 		ENC_FREE(enc);
932 		return (CAM_REQ_CMP_ERR);
933 	}
934 
935 	if (err) {
936 		xpt_print(periph->path, "error %d initializing\n", err);
937 		goto out;
938 	}
939 
940 	/*
941 	 * Hold off userland until we have made at least one pass
942 	 * through our state machine so that physical path data is
943 	 * present.
944 	 */
945 	if (enc->enc_vec.poll_status != NULL) {
946 		root_mount_hold_token(periph->periph_name, &enc->enc_rootmount);
947 	}
948 
949 	/*
950 	 * The softc field is set only once the enc is fully initialized
951 	 * so that we can rely on this field to detect partially
952 	 * initialized periph objects in the AC_FOUND_DEVICE handler.
953 	 */
954 	periph->softc = enc;
955 
956 	cam_periph_unlock(periph);
957 	if (enc->enc_vec.poll_status != NULL) {
958 		err = enc_kproc_init(enc);
959 		if (err) {
960 			xpt_print(periph->path,
961 				  "error %d starting enc_daemon\n", err);
962 			goto out;
963 		}
964 	}
965 
966 	/*
967 	 * Acquire a reference to the periph before we create the devfs
968 	 * instance for it.  We'll release this reference once the devfs
969 	 * instance has been freed.
970 	 */
971 	if (cam_periph_acquire(periph) != 0) {
972 		xpt_print(periph->path, "%s: lost periph during "
973 			  "registration!\n", __func__);
974 		cam_periph_lock(periph);
975 
976 		return (CAM_REQ_CMP_ERR);
977 	}
978 
979 	make_dev_args_init(&args);
980 	args.mda_devsw = &enc_cdevsw;
981 	args.mda_unit = periph->unit_number;
982 	args.mda_uid = UID_ROOT;
983 	args.mda_gid = GID_OPERATOR;
984 	args.mda_mode = 0600;
985 	args.mda_si_drv1 = periph;
986 	err = make_dev_s(&args, &enc->enc_dev, "%s%d", periph->periph_name,
987 	    periph->unit_number);
988 	cam_periph_lock(periph);
989 	if (err != 0) {
990 		cam_periph_release_locked(periph);
991 		return (CAM_REQ_CMP_ERR);
992 	}
993 
994 	enc->enc_flags |= ENC_FLAG_INITIALIZED;
995 
996 	/*
997 	 * Add an async callback so that we get notified if this
998 	 * device goes away.
999 	 */
1000 	xpt_register_async(AC_LOST_DEVICE, enc_async, periph, periph->path);
1001 
1002 	switch (enc->enc_type) {
1003 	default:
1004 	case ENC_NONE:
1005 		tname = "No ENC device";
1006 		break;
1007 	case ENC_SES:
1008 		tname = "SES Device";
1009 		break;
1010         case ENC_SES_PASSTHROUGH:
1011 		tname = "SES Passthrough Device";
1012 		break;
1013         case ENC_SAFT:
1014 		tname = "SAF-TE Device";
1015 		break;
1016 	case ENC_SEMB_SES:
1017 		tname = "SEMB SES Device";
1018 		break;
1019 	case ENC_SEMB_SAFT:
1020 		tname = "SEMB SAF-TE Device";
1021 		break;
1022 	}
1023 
1024 	sbuf_new(&sb, enc->announce_buf, ENC_ANNOUNCE_SZ, SBUF_FIXEDLEN);
1025 	xpt_announce_periph_sbuf(periph, &sb, tname);
1026 	sbuf_finish(&sb);
1027 	sbuf_putbuf(&sb);
1028 
1029 	status = CAM_REQ_CMP;
1030 
1031 out:
1032 	if (status != CAM_REQ_CMP)
1033 		enc_dtor(periph);
1034 	return (status);
1035 }
1036