xref: /openbsd-src/sys/dev/vscsi.c (revision ae3cb403620ab940fbaabb3055fac045a63d56b7)
1 /*	$OpenBSD: vscsi.c,v 1.41 2017/02/12 17:12:37 chl Exp $ */
2 
3 /*
4  * Copyright (c) 2008 David Gwynne <dlg@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/param.h>
20 #include <sys/systm.h>
21 #include <sys/kernel.h>
22 #include <sys/malloc.h>
23 #include <sys/device.h>
24 #include <sys/conf.h>
25 #include <sys/queue.h>
26 #include <sys/rwlock.h>
27 #include <sys/pool.h>
28 #include <sys/task.h>
29 #include <sys/ioctl.h>
30 #include <sys/poll.h>
31 #include <sys/selinfo.h>
32 
33 #include <scsi/scsi_all.h>
34 #include <scsi/scsiconf.h>
35 
36 #include <dev/vscsivar.h>
37 
38 int		vscsi_match(struct device *, void *, void *);
39 void		vscsi_attach(struct device *, struct device *, void *);
40 void		vscsi_shutdown(void *);
41 
42 struct vscsi_ccb {
43 	TAILQ_ENTRY(vscsi_ccb)	ccb_entry;
44 	int			ccb_tag;
45 	struct scsi_xfer	*ccb_xs;
46 	size_t			ccb_datalen;
47 };
48 
49 TAILQ_HEAD(vscsi_ccb_list, vscsi_ccb);
50 
51 enum vscsi_state {
52 	VSCSI_S_CLOSED,
53 	VSCSI_S_CONFIG,
54 	VSCSI_S_RUNNING
55 };
56 
57 struct vscsi_softc {
58 	struct device		sc_dev;
59 	struct scsi_link	sc_link;
60 	struct scsibus_softc	*sc_scsibus;
61 
62 	struct mutex		sc_state_mtx;
63 	enum vscsi_state	sc_state;
64 	u_int			sc_ref_count;
65 	struct pool		sc_ccb_pool;
66 
67 	struct scsi_iopool	sc_iopool;
68 
69 	struct vscsi_ccb_list	sc_ccb_i2t;
70 	struct vscsi_ccb_list	sc_ccb_t2i;
71 	int			sc_ccb_tag;
72 	struct mutex		sc_poll_mtx;
73 	struct rwlock		sc_ioc_lock;
74 
75 	struct selinfo		sc_sel;
76 	struct mutex		sc_sel_mtx;
77 };
78 
79 #define DEVNAME(_s) ((_s)->sc_dev.dv_xname)
80 #define DEV2SC(_d) ((struct vscsi_softc *)device_lookup(&vscsi_cd, minor(_d)))
81 
82 struct cfattach vscsi_ca = {
83 	sizeof(struct vscsi_softc),
84 	vscsi_match,
85 	vscsi_attach
86 };
87 
88 struct cfdriver vscsi_cd = {
89 	NULL,
90 	"vscsi",
91 	DV_DULL
92 };
93 
94 void		vscsi_cmd(struct scsi_xfer *);
95 int		vscsi_probe(struct scsi_link *);
96 void		vscsi_free(struct scsi_link *);
97 
98 struct scsi_adapter vscsi_switch = {
99 	vscsi_cmd,
100 	scsi_minphys,
101 	vscsi_probe,
102 	vscsi_free
103 };
104 
105 int		vscsi_i2t(struct vscsi_softc *, struct vscsi_ioc_i2t *);
106 int		vscsi_data(struct vscsi_softc *, struct vscsi_ioc_data *, int);
107 int		vscsi_t2i(struct vscsi_softc *, struct vscsi_ioc_t2i *);
108 int		vscsi_devevent(struct vscsi_softc *, u_long,
109 		    struct vscsi_ioc_devevent *);
110 void		vscsi_devevent_task(void *);
111 void		vscsi_done(struct vscsi_softc *, struct vscsi_ccb *);
112 
113 void *		vscsi_ccb_get(void *);
114 void		vscsi_ccb_put(void *, void *);
115 
116 void		filt_vscsidetach(struct knote *);
117 int		filt_vscsiread(struct knote *, long);
118 
119 struct filterops vscsi_filtops = {
120 	1,
121 	NULL,
122 	filt_vscsidetach,
123 	filt_vscsiread
124 };
125 
126 
127 int
128 vscsi_match(struct device *parent, void *match, void *aux)
129 {
130 	return (1);
131 }
132 
133 void
134 vscsi_attach(struct device *parent, struct device *self, void *aux)
135 {
136 	struct vscsi_softc		*sc = (struct vscsi_softc *)self;
137 	struct scsibus_attach_args	saa;
138 
139 	printf("\n");
140 
141 	mtx_init(&sc->sc_state_mtx, IPL_BIO);
142 	sc->sc_state = VSCSI_S_CLOSED;
143 
144 	TAILQ_INIT(&sc->sc_ccb_i2t);
145 	TAILQ_INIT(&sc->sc_ccb_t2i);
146 	mtx_init(&sc->sc_poll_mtx, IPL_BIO);
147 	mtx_init(&sc->sc_sel_mtx, IPL_BIO);
148 	rw_init(&sc->sc_ioc_lock, "vscsiioc");
149 	scsi_iopool_init(&sc->sc_iopool, sc, vscsi_ccb_get, vscsi_ccb_put);
150 
151 	sc->sc_link.adapter = &vscsi_switch;
152 	sc->sc_link.adapter_softc = sc;
153 	sc->sc_link.adapter_target = 256;
154 	sc->sc_link.adapter_buswidth = 256;
155 	sc->sc_link.openings = 16;
156 	sc->sc_link.pool = &sc->sc_iopool;
157 
158 	memset(&saa, 0, sizeof(saa));
159 	saa.saa_sc_link = &sc->sc_link;
160 
161 	sc->sc_scsibus = (struct scsibus_softc *)config_found(&sc->sc_dev,
162 	    &saa, scsiprint);
163 }
164 
165 void
166 vscsi_cmd(struct scsi_xfer *xs)
167 {
168 	struct scsi_link		*link = xs->sc_link;
169 	struct vscsi_softc		*sc = link->adapter_softc;
170 	struct vscsi_ccb		*ccb = xs->io;
171 	int				polled = ISSET(xs->flags, SCSI_POLL);
172 	int				running = 0;
173 
174 	if (ISSET(xs->flags, SCSI_POLL) && ISSET(xs->flags, SCSI_NOSLEEP)) {
175 		printf("%s: POLL && NOSLEEP for 0x%02x\n", DEVNAME(sc),
176 		    xs->cmd->opcode);
177 		xs->error = XS_DRIVER_STUFFUP;
178 		scsi_done(xs);
179 		return;
180 	}
181 
182 	ccb->ccb_xs = xs;
183 
184 	mtx_enter(&sc->sc_state_mtx);
185 	if (sc->sc_state == VSCSI_S_RUNNING) {
186 		running = 1;
187 		TAILQ_INSERT_TAIL(&sc->sc_ccb_i2t, ccb, ccb_entry);
188 	}
189 	mtx_leave(&sc->sc_state_mtx);
190 
191 	if (!running) {
192 		xs->error = XS_DRIVER_STUFFUP;
193 		scsi_done(xs);
194 		return;
195 	}
196 
197 	selwakeup(&sc->sc_sel);
198 
199 	if (polled) {
200 		mtx_enter(&sc->sc_poll_mtx);
201 		while (ccb->ccb_xs != NULL)
202 			msleep(ccb, &sc->sc_poll_mtx, PRIBIO, "vscsipoll", 0);
203 		mtx_leave(&sc->sc_poll_mtx);
204 		scsi_done(xs);
205 	}
206 }
207 
208 void
209 vscsi_done(struct vscsi_softc *sc, struct vscsi_ccb *ccb)
210 {
211 	struct scsi_xfer		*xs = ccb->ccb_xs;
212 
213 	if (ISSET(xs->flags, SCSI_POLL)) {
214 		mtx_enter(&sc->sc_poll_mtx);
215 		ccb->ccb_xs = NULL;
216 		wakeup(ccb);
217 		mtx_leave(&sc->sc_poll_mtx);
218 	} else
219 		scsi_done(xs);
220 }
221 
222 int
223 vscsi_probe(struct scsi_link *link)
224 {
225 	struct vscsi_softc		*sc = link->adapter_softc;
226 	int				rv = 0;
227 
228 	mtx_enter(&sc->sc_state_mtx);
229 	if (sc->sc_state == VSCSI_S_RUNNING)
230 		sc->sc_ref_count++;
231 	else
232 		rv = ENXIO;
233 	mtx_leave(&sc->sc_state_mtx);
234 
235 	return (rv);
236 }
237 
238 void
239 vscsi_free(struct scsi_link *link)
240 {
241 	struct vscsi_softc		*sc = link->adapter_softc;
242 
243 	mtx_enter(&sc->sc_state_mtx);
244 	sc->sc_ref_count--;
245 	if (sc->sc_state != VSCSI_S_RUNNING && sc->sc_ref_count == 0)
246 		wakeup(&sc->sc_ref_count);
247 	mtx_leave(&sc->sc_state_mtx);
248 }
249 
250 int
251 vscsiopen(dev_t dev, int flags, int mode, struct proc *p)
252 {
253 	struct vscsi_softc		*sc = DEV2SC(dev);
254 	enum vscsi_state		state = VSCSI_S_RUNNING;
255 	int				rv = 0;
256 
257 	if (sc == NULL)
258 		return (ENXIO);
259 
260 	mtx_enter(&sc->sc_state_mtx);
261 	if (sc->sc_state != VSCSI_S_CLOSED)
262 		rv = EBUSY;
263 	else
264 		sc->sc_state = VSCSI_S_CONFIG;
265 	mtx_leave(&sc->sc_state_mtx);
266 
267 	if (rv != 0) {
268 		device_unref(&sc->sc_dev);
269 		return (rv);
270 	}
271 
272 	pool_init(&sc->sc_ccb_pool, sizeof(struct vscsi_ccb), 0, IPL_BIO, 0,
273 	    "vscsiccb", NULL);
274 
275 	/* we need to guarantee some ccbs will be available for the iopool */
276 	rv = pool_prime(&sc->sc_ccb_pool, 8);
277 	if (rv != 0) {
278 		pool_destroy(&sc->sc_ccb_pool);
279 		state = VSCSI_S_CLOSED;
280 	}
281 
282 	/* commit changes */
283 	mtx_enter(&sc->sc_state_mtx);
284 	sc->sc_state = state;
285 	mtx_leave(&sc->sc_state_mtx);
286 
287 	device_unref(&sc->sc_dev);
288 	return (rv);
289 }
290 
291 int
292 vscsiioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
293 {
294 	struct vscsi_softc		*sc = DEV2SC(dev);
295 	int				read = 0;
296 	int				err = 0;
297 
298 	if (sc == NULL)
299 		return (ENXIO);
300 
301 	rw_enter_write(&sc->sc_ioc_lock);
302 
303 	switch (cmd) {
304 	case VSCSI_I2T:
305 		err = vscsi_i2t(sc, (struct vscsi_ioc_i2t *)addr);
306 		break;
307 
308 	case VSCSI_DATA_READ:
309 		read = 1;
310 	case VSCSI_DATA_WRITE:
311 		err = vscsi_data(sc, (struct vscsi_ioc_data *)addr, read);
312 		break;
313 
314 	case VSCSI_T2I:
315 		err = vscsi_t2i(sc, (struct vscsi_ioc_t2i *)addr);
316 		break;
317 
318 	case VSCSI_REQPROBE:
319 	case VSCSI_REQDETACH:
320 		err = vscsi_devevent(sc, cmd,
321 		    (struct vscsi_ioc_devevent *)addr);
322 		break;
323 
324 	default:
325 		err = ENOTTY;
326 		break;
327 	}
328 
329 	rw_exit_write(&sc->sc_ioc_lock);
330 
331 	device_unref(&sc->sc_dev);
332 	return (err);
333 }
334 
335 int
336 vscsi_i2t(struct vscsi_softc *sc, struct vscsi_ioc_i2t *i2t)
337 {
338 	struct vscsi_ccb		*ccb;
339 	struct scsi_xfer		*xs;
340 	struct scsi_link		*link;
341 
342 	mtx_enter(&sc->sc_state_mtx);
343 	ccb = TAILQ_FIRST(&sc->sc_ccb_i2t);
344 	if (ccb != NULL)
345 		TAILQ_REMOVE(&sc->sc_ccb_i2t, ccb, ccb_entry);
346 	mtx_leave(&sc->sc_state_mtx);
347 
348 	if (ccb == NULL)
349 		return (EAGAIN);
350 
351 	xs = ccb->ccb_xs;
352 	link = xs->sc_link;
353 
354 	i2t->tag = ccb->ccb_tag;
355 	i2t->target = link->target;
356 	i2t->lun = link->lun;
357 	memcpy(&i2t->cmd, xs->cmd, xs->cmdlen);
358 	i2t->cmdlen = xs->cmdlen;
359 	i2t->datalen = xs->datalen;
360 
361 	switch (xs->flags & (SCSI_DATA_IN | SCSI_DATA_OUT)) {
362 	case SCSI_DATA_IN:
363 		i2t->direction = VSCSI_DIR_READ;
364 		break;
365 	case SCSI_DATA_OUT:
366 		i2t->direction = VSCSI_DIR_WRITE;
367 		break;
368 	default:
369 		i2t->direction = VSCSI_DIR_NONE;
370 		break;
371 	}
372 
373 	TAILQ_INSERT_TAIL(&sc->sc_ccb_t2i, ccb, ccb_entry);
374 
375 	return (0);
376 }
377 
378 int
379 vscsi_data(struct vscsi_softc *sc, struct vscsi_ioc_data *data, int read)
380 {
381 	struct vscsi_ccb		*ccb;
382 	struct scsi_xfer		*xs;
383 	int				xsread;
384 	u_int8_t			*buf;
385 	int				rv = EINVAL;
386 
387 	TAILQ_FOREACH(ccb, &sc->sc_ccb_t2i, ccb_entry) {
388 		if (ccb->ccb_tag == data->tag)
389 			break;
390 	}
391 	if (ccb == NULL)
392 		return (EFAULT);
393 
394 	xs = ccb->ccb_xs;
395 
396 	if (data->datalen > xs->datalen - ccb->ccb_datalen)
397 		return (ENOMEM);
398 
399 	switch (xs->flags & (SCSI_DATA_IN | SCSI_DATA_OUT)) {
400 	case SCSI_DATA_IN:
401 		xsread = 1;
402 		break;
403 	case SCSI_DATA_OUT:
404 		xsread = 0;
405 		break;
406 	default:
407 		return (EINVAL);
408 	}
409 
410 	if (read != xsread)
411 		return (EINVAL);
412 
413 	buf = xs->data;
414 	buf += ccb->ccb_datalen;
415 
416 	if (read)
417 		rv = copyin(data->data, buf, data->datalen);
418 	else
419 		rv = copyout(buf, data->data, data->datalen);
420 
421 	if (rv == 0)
422 		ccb->ccb_datalen += data->datalen;
423 
424 	return (rv);
425 }
426 
427 int
428 vscsi_t2i(struct vscsi_softc *sc, struct vscsi_ioc_t2i *t2i)
429 {
430 	struct vscsi_ccb		*ccb;
431 	struct scsi_xfer		*xs;
432 	int				rv = 0;
433 
434 	TAILQ_FOREACH(ccb, &sc->sc_ccb_t2i, ccb_entry) {
435 		if (ccb->ccb_tag == t2i->tag)
436 			break;
437 	}
438 	if (ccb == NULL)
439 		return (EFAULT);
440 
441 	TAILQ_REMOVE(&sc->sc_ccb_t2i, ccb, ccb_entry);
442 
443 	xs = ccb->ccb_xs;
444 
445 	xs->resid = xs->datalen - ccb->ccb_datalen;
446 	xs->status = SCSI_OK;
447 
448 	switch (t2i->status) {
449 	case VSCSI_STAT_DONE:
450 		xs->error = XS_NOERROR;
451 		break;
452 	case VSCSI_STAT_SENSE:
453 		xs->error = XS_SENSE;
454 		memcpy(&xs->sense, &t2i->sense, sizeof(xs->sense));
455 		break;
456 	case VSCSI_STAT_RESET:
457 		xs->error = XS_RESET;
458 		break;
459 	case VSCSI_STAT_ERR:
460 	default:
461 		xs->error = XS_DRIVER_STUFFUP;
462 		break;
463 	}
464 
465 	vscsi_done(sc, ccb);
466 
467 	return (rv);
468 }
469 
470 struct vscsi_devevent_task {
471 	struct vscsi_softc *sc;
472 	struct task t;
473 	struct vscsi_ioc_devevent de;
474 	u_long cmd;
475 };
476 
477 int
478 vscsi_devevent(struct vscsi_softc *sc, u_long cmd,
479     struct vscsi_ioc_devevent *de)
480 {
481 	struct vscsi_devevent_task *dt;
482 
483 	dt = malloc(sizeof(*dt), M_TEMP, M_WAITOK | M_CANFAIL);
484 	if (dt == NULL)
485 		return (ENOMEM);
486 
487 	task_set(&dt->t, vscsi_devevent_task, dt);
488 	dt->sc = sc;
489 	dt->de = *de;
490 	dt->cmd = cmd;
491 
492 	device_ref(&sc->sc_dev);
493 	task_add(systq, &dt->t);
494 
495 	return (0);
496 }
497 
498 void
499 vscsi_devevent_task(void *xdt)
500 {
501 	struct vscsi_devevent_task *dt = xdt;
502 	struct vscsi_softc *sc = dt->sc;
503 	int state;
504 
505 	mtx_enter(&sc->sc_state_mtx);
506 	state = sc->sc_state;
507 	mtx_leave(&sc->sc_state_mtx);
508 
509 	if (state != VSCSI_S_RUNNING)
510 		goto gone;
511 
512 	switch (dt->cmd) {
513 	case VSCSI_REQPROBE:
514 		scsi_probe(sc->sc_scsibus, dt->de.target, dt->de.lun);
515 		break;
516 	case VSCSI_REQDETACH:
517 		scsi_detach(sc->sc_scsibus, dt->de.target, dt->de.lun,
518 		    DETACH_FORCE);
519 		break;
520 #ifdef DIAGNOSTIC
521 	default:
522 		panic("unexpected vscsi_devevent cmd");
523 		/* NOTREACHED */
524 #endif
525 	}
526 
527 gone:
528 	device_unref(&sc->sc_dev);
529 
530 	free(dt, M_TEMP, sizeof(*dt));
531 }
532 
533 int
534 vscsipoll(dev_t dev, int events, struct proc *p)
535 {
536 	struct vscsi_softc		*sc = DEV2SC(dev);
537 	int				revents = 0;
538 
539 	if (sc == NULL)
540 		return (ENXIO);
541 
542 	if (events & (POLLIN | POLLRDNORM)) {
543 		mtx_enter(&sc->sc_state_mtx);
544 		if (!TAILQ_EMPTY(&sc->sc_ccb_i2t))
545 			revents |= events & (POLLIN | POLLRDNORM);
546 		mtx_leave(&sc->sc_state_mtx);
547 	}
548 
549 	if (revents == 0) {
550 		if (events & (POLLIN | POLLRDNORM))
551 			selrecord(p, &sc->sc_sel);
552 	}
553 
554 	device_unref(&sc->sc_dev);
555 	return (revents);
556 }
557 
558 int
559 vscsikqfilter(dev_t dev, struct knote *kn)
560 {
561 	struct vscsi_softc *sc = DEV2SC(dev);
562 	struct klist *klist;
563 
564 	if (sc == NULL)
565 		return (ENXIO);
566 
567 	klist = &sc->sc_sel.si_note;
568 
569 	switch (kn->kn_filter) {
570 	case EVFILT_READ:
571 		kn->kn_fop = &vscsi_filtops;
572 		break;
573 	default:
574 		device_unref(&sc->sc_dev);
575 		return (EINVAL);
576 	}
577 
578 	kn->kn_hook = sc;
579 
580 	mtx_enter(&sc->sc_sel_mtx);
581 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
582 	mtx_leave(&sc->sc_sel_mtx);
583 
584 	/* device ref is given to the knote in the klist */
585 
586 	return (0);
587 }
588 
589 void
590 filt_vscsidetach(struct knote *kn)
591 {
592 	struct vscsi_softc *sc = kn->kn_hook;
593 	struct klist *klist = &sc->sc_sel.si_note;
594 
595 	mtx_enter(&sc->sc_sel_mtx);
596 	SLIST_REMOVE(klist, kn, knote, kn_selnext);
597 	mtx_leave(&sc->sc_sel_mtx);
598 
599 	device_unref(&sc->sc_dev);
600 }
601 
602 int
603 filt_vscsiread(struct knote *kn, long hint)
604 {
605 	struct vscsi_softc *sc = kn->kn_hook;
606 	int event = 0;
607 
608 	mtx_enter(&sc->sc_state_mtx);
609 	if (!TAILQ_EMPTY(&sc->sc_ccb_i2t))
610 		event = 1;
611 	mtx_leave(&sc->sc_state_mtx);
612 
613 	return (event);
614 }
615 
616 int
617 vscsiclose(dev_t dev, int flags, int mode, struct proc *p)
618 {
619 	struct vscsi_softc		*sc = DEV2SC(dev);
620 	struct vscsi_ccb		*ccb;
621 
622 	if (sc == NULL)
623 		return (ENXIO);
624 
625 	mtx_enter(&sc->sc_state_mtx);
626 	KASSERT(sc->sc_state == VSCSI_S_RUNNING);
627 	sc->sc_state = VSCSI_S_CONFIG;
628 	mtx_leave(&sc->sc_state_mtx);
629 
630 	scsi_activate(sc->sc_scsibus, -1, -1, DVACT_DEACTIVATE);
631 
632 	while ((ccb = TAILQ_FIRST(&sc->sc_ccb_t2i)) != NULL) {
633 		TAILQ_REMOVE(&sc->sc_ccb_t2i, ccb, ccb_entry);
634 		ccb->ccb_xs->error = XS_RESET;
635 		vscsi_done(sc, ccb);
636 	}
637 
638 	while ((ccb = TAILQ_FIRST(&sc->sc_ccb_i2t)) != NULL) {
639 		TAILQ_REMOVE(&sc->sc_ccb_i2t, ccb, ccb_entry);
640 		ccb->ccb_xs->error = XS_RESET;
641 		vscsi_done(sc, ccb);
642 	}
643 
644 	scsi_req_detach(sc->sc_scsibus, -1, -1, DETACH_FORCE);
645 
646 	mtx_enter(&sc->sc_state_mtx);
647 	while (sc->sc_ref_count > 0) {
648 		msleep(&sc->sc_ref_count, &sc->sc_state_mtx,
649 		    PRIBIO, "vscsiref", 0);
650 	}
651 	mtx_leave(&sc->sc_state_mtx);
652 
653 	pool_destroy(&sc->sc_ccb_pool);
654 
655 	mtx_enter(&sc->sc_state_mtx);
656 	sc->sc_state = VSCSI_S_CLOSED;
657 	mtx_leave(&sc->sc_state_mtx);
658 
659 	device_unref(&sc->sc_dev);
660 	return (0);
661 }
662 
663 void *
664 vscsi_ccb_get(void *cookie)
665 {
666 	struct vscsi_softc		*sc = cookie;
667 	struct vscsi_ccb		*ccb = NULL;
668 
669 	ccb = pool_get(&sc->sc_ccb_pool, PR_NOWAIT);
670 	if (ccb != NULL) {
671 		ccb->ccb_tag = sc->sc_ccb_tag++;
672 		ccb->ccb_datalen = 0;
673 	}
674 
675 	return (ccb);
676 }
677 
678 void
679 vscsi_ccb_put(void *cookie, void *io)
680 {
681 	struct vscsi_softc		*sc = cookie;
682 	struct vscsi_ccb		*ccb = io;
683 
684 	pool_put(&sc->sc_ccb_pool, ccb);
685 }
686