xref: /netbsd-src/sys/dev/pci/vioscsi.c (revision 338c7befb9a157acd3b80c873d6f500f60789636)
1 /*	$NetBSD: vioscsi.c,v 1.36 2023/03/25 11:04:34 mlelstv Exp $	*/
2 /*	$OpenBSD: vioscsi.c,v 1.3 2015/03/14 03:38:49 jsg Exp $	*/
3 
4 /*
5  * Copyright (c) 2013 Google Inc.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/cdefs.h>
21 __KERNEL_RCSID(0, "$NetBSD: vioscsi.c,v 1.36 2023/03/25 11:04:34 mlelstv Exp $");
22 
23 #include <sys/param.h>
24 #include <sys/systm.h>
25 #include <sys/device.h>
26 #include <sys/bus.h>
27 #include <sys/buf.h>
28 #include <sys/module.h>
29 
30 #include <dev/pci/vioscsireg.h>
31 #include <dev/pci/virtiovar.h>
32 
33 #include <dev/scsipi/scsi_all.h>
34 #include <dev/scsipi/scsiconf.h>
35 
36 #ifdef VIOSCSI_DEBUG
37 static int vioscsi_debug = 1;
38 #define DPRINTF(f) do { if (vioscsi_debug) printf f; } while (/*CONSTCOND*/0)
39 #else
40 #define DPRINTF(f) ((void)0)
41 #endif
42 
43 struct vioscsi_req {
44 	struct virtio_scsi_req_hdr	 vr_req;
45 	struct virtio_scsi_res_hdr	 vr_res;
46 	struct scsipi_xfer		*vr_xs;
47 	bus_dmamap_t			 vr_control;
48 	bus_dmamap_t			 vr_data;
49 };
50 
51 struct vioscsi_softc {
52 	device_t 		 sc_dev;
53 	struct scsipi_adapter	 sc_adapter;
54 	struct scsipi_channel 	 sc_channel;
55 
56 	struct virtqueue	 sc_vqs[3];
57 #define VIOSCSI_VQ_CONTROL	0
58 #define VIOSCSI_VQ_EVENT	1
59 #define VIOSCSI_VQ_REQUEST	2
60 
61 	struct vioscsi_req	*sc_reqs;
62 	int			 sc_nreqs;
63 	bus_dma_segment_t        sc_reqs_segs[1];
64 
65 	u_int32_t		 sc_seg_max;
66 
67 	kmutex_t		 sc_mutex;
68 };
69 
70 /*
71  * Each block request uses at least two segments - one for the header
72  * and one for the status.
73 */
74 #define VIRTIO_SCSI_MIN_SEGMENTS 2
75 
76 static int	 vioscsi_match(device_t, cfdata_t, void *);
77 static void	 vioscsi_attach(device_t, device_t, void *);
78 static int	 vioscsi_detach(device_t, int);
79 
80 static int	 vioscsi_alloc_reqs(struct vioscsi_softc *,
81     struct virtio_softc *, int);
82 static void	 vioscsi_free_reqs(struct vioscsi_softc *,
83     struct virtio_softc *);
84 static void	 vioscsi_scsipi_request(struct scsipi_channel *,
85     scsipi_adapter_req_t, void *);
86 static int	 vioscsi_vq_done(struct virtqueue *);
87 static void	 vioscsi_req_done(struct vioscsi_softc *, struct virtio_softc *,
88     struct vioscsi_req *, struct virtqueue *, int);
89 static struct vioscsi_req *vioscsi_req_get(struct vioscsi_softc *);
90 static void	 vioscsi_bad_target(struct scsipi_xfer *);
91 
92 static const char *const vioscsi_vq_names[] = {
93 	"control",
94 	"event",
95 	"request",
96 };
97 
98 CFATTACH_DECL3_NEW(vioscsi, sizeof(struct vioscsi_softc),
99     vioscsi_match, vioscsi_attach, vioscsi_detach, NULL, NULL, NULL,
100     DVF_DETACH_SHUTDOWN);
101 
102 static int
vioscsi_match(device_t parent,cfdata_t match,void * aux)103 vioscsi_match(device_t parent, cfdata_t match, void *aux)
104 {
105 	struct virtio_attach_args *va = aux;
106 
107 	if (va->sc_childdevid == VIRTIO_DEVICE_ID_SCSI)
108 		return 1;
109 
110 	return 0;
111 }
112 
113 static void
vioscsi_attach(device_t parent,device_t self,void * aux)114 vioscsi_attach(device_t parent, device_t self, void *aux)
115 {
116 	struct vioscsi_softc *sc = device_private(self);
117 	struct virtio_softc *vsc = device_private(parent);
118 	struct scsipi_adapter *adapt = &sc->sc_adapter;
119 	struct scsipi_channel *chan = &sc->sc_channel;
120 	int rv, qsize = 0, i = 0;
121 	int ipl = IPL_BIO;
122 
123 	if (virtio_child(vsc) != NULL) {
124 		aprint_error(": parent %s already has a child\n",
125 		    device_xname(parent));
126 		return;
127 	}
128 
129 	sc->sc_dev = self;
130 
131 	virtio_child_attach_start(vsc, self, ipl,
132 	    0, VIRTIO_COMMON_FLAG_BITS);
133 
134 	mutex_init(&sc->sc_mutex, MUTEX_DEFAULT, ipl);
135 
136 	uint32_t cmd_per_lun = virtio_read_device_config_4(vsc,
137 	    VIRTIO_SCSI_CONFIG_CMD_PER_LUN);
138 
139 	uint32_t seg_max = virtio_read_device_config_4(vsc,
140 	    VIRTIO_SCSI_CONFIG_SEG_MAX);
141 
142 	uint16_t max_target = virtio_read_device_config_2(vsc,
143 	    VIRTIO_SCSI_CONFIG_MAX_TARGET);
144 
145 	uint32_t max_lun = virtio_read_device_config_4(vsc,
146 	    VIRTIO_SCSI_CONFIG_MAX_LUN);
147 
148 	sc->sc_seg_max = seg_max;
149 
150 	for(i=0; i < __arraycount(sc->sc_vqs); i++) {
151 		virtio_init_vq_vqdone(vsc, &sc->sc_vqs[i], i,
152 		    vioscsi_vq_done);
153 		rv = virtio_alloc_vq(vsc, &sc->sc_vqs[i], MAXPHYS,
154 		    VIRTIO_SCSI_MIN_SEGMENTS + howmany(MAXPHYS, NBPG),
155 		    vioscsi_vq_names[i]);
156 		if (rv) {
157 			aprint_error_dev(sc->sc_dev,
158 			    "failed to allocate virtqueue %d\n", i);
159 			goto err;
160 		}
161 
162 		if (i == VIOSCSI_VQ_REQUEST)
163 			sc->sc_vqs[i].vq_done = vioscsi_vq_done;
164 	}
165 
166 	qsize = sc->sc_vqs[VIOSCSI_VQ_REQUEST].vq_num;
167 	if (vioscsi_alloc_reqs(sc, vsc, qsize))
168 		goto err;
169 
170 	aprint_normal_dev(sc->sc_dev,
171 	    "cmd_per_lun %u qsize %d seg_max %u max_target %hu"
172 	    " max_lun %u\n",
173 	    cmd_per_lun, qsize, seg_max, max_target, max_lun);
174 
175 	if (virtio_child_attach_finish(vsc, sc->sc_vqs,
176 	    __arraycount(sc->sc_vqs), NULL,
177 	    VIRTIO_F_INTR_MSIX | VIRTIO_F_INTR_MPSAFE) != 0)
178 		goto err;
179 
180 	/*
181 	 * Fill in the scsipi_adapter.
182 	 */
183 	memset(adapt, 0, sizeof(*adapt));
184 	adapt->adapt_dev = sc->sc_dev;
185 	adapt->adapt_nchannels = 1;
186 	adapt->adapt_openings = MIN(qsize, cmd_per_lun);
187 	adapt->adapt_max_periph = adapt->adapt_openings;
188 	adapt->adapt_request = vioscsi_scsipi_request;
189 	adapt->adapt_minphys = minphys;
190 	adapt->adapt_flags = SCSIPI_ADAPT_MPSAFE;
191 
192 	/*
193 	 * Fill in the scsipi_channel.
194 	 */
195 	memset(chan, 0, sizeof(*chan));
196 	chan->chan_adapter = adapt;
197 	chan->chan_bustype = &scsi_bustype;
198 	chan->chan_channel = 0;
199 	chan->chan_ntargets = MIN(1 + max_target, 256);	/* cap reasonably */
200 	chan->chan_nluns = MIN(1 + max_lun, 16384);	/* cap reasonably */
201 	chan->chan_id = max_target + 1;
202 	chan->chan_flags = SCSIPI_CHAN_NOSETTLE;
203 
204 	config_found(self, &sc->sc_channel, scsiprint, CFARGS_NONE);
205 	return;
206 
207 err:
208 	if (qsize > 0)
209 		vioscsi_free_reqs(sc, vsc);
210 
211 	for (i=0; i < __arraycount(sc->sc_vqs); i++) {
212 		virtio_free_vq(vsc, &sc->sc_vqs[i]);
213 	}
214 
215 	virtio_child_attach_failed(vsc);
216 }
217 
218 static int
vioscsi_detach(device_t self,int flags)219 vioscsi_detach(device_t self, int flags)
220 {
221 	struct vioscsi_softc *sc = device_private(self);
222 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
223 	int rc, i;
224 
225 	/*
226 	 * Dequeue all pending finished requests. Must be done
227 	 * before we try to detach children so that we process
228 	 * their pending requests while they still exist.
229 	 */
230 	if (sc->sc_vqs[VIOSCSI_VQ_REQUEST].vq_num > 0)
231 		vioscsi_vq_done(&sc->sc_vqs[VIOSCSI_VQ_REQUEST]);
232 
233 	if ((rc = config_detach_children(self, flags)) != 0)
234 		return rc;
235 
236 	virtio_reset(vsc);
237 
238 	for (i = 0; i < __arraycount(sc->sc_vqs); i++) {
239 		if (sc->sc_vqs[i].vq_num > 0)
240 			virtio_free_vq(vsc, &sc->sc_vqs[i]);
241 	}
242 
243 	vioscsi_free_reqs(sc, vsc);
244 
245 	virtio_child_detach(vsc);
246 
247 	mutex_destroy(&sc->sc_mutex);
248 
249 	return 0;
250 }
251 
252 #define XS2DMA(xs) \
253     ((((xs)->xs_control & XS_CTL_DATA_IN) ? BUS_DMA_READ : BUS_DMA_WRITE) | \
254     (((xs)->xs_control & XS_CTL_NOSLEEP) ? BUS_DMA_NOWAIT : BUS_DMA_WAITOK) | \
255     BUS_DMA_STREAMING)
256 
257 #define XS2DMAPRE(xs) (((xs)->xs_control & XS_CTL_DATA_IN) ? \
258     BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE)
259 
260 #define XS2DMAPOST(xs) (((xs)->xs_control & XS_CTL_DATA_IN) ? \
261     BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE)
262 
263 static void
vioscsi_scsipi_request(struct scsipi_channel * chan,scsipi_adapter_req_t request,void * arg)264 vioscsi_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t
265     request, void *arg)
266 {
267 	struct vioscsi_softc *sc =
268 	    device_private(chan->chan_adapter->adapt_dev);
269 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
270 	struct scsipi_xfer *xs;
271 	struct scsipi_periph *periph;
272 	struct vioscsi_req *vr;
273 	struct virtio_scsi_req_hdr *req;
274 	struct virtqueue *vq = &sc->sc_vqs[VIOSCSI_VQ_REQUEST];
275 	int slot, error;
276 	bool dopoll;
277 
278 	DPRINTF(("%s: enter\n", __func__));
279 
280 	switch (request) {
281 	case ADAPTER_REQ_RUN_XFER:
282 		break;
283 	case ADAPTER_REQ_SET_XFER_MODE:
284 	{
285 		struct scsipi_xfer_mode *xm = arg;
286 		xm->xm_mode = PERIPH_CAP_TQING;
287 		xm->xm_period = 0;
288 		xm->xm_offset = 0;
289 		scsipi_async_event(chan, ASYNC_EVENT_XFER_MODE, xm);
290 		return;
291 	}
292 	default:
293 		DPRINTF(("%s: unhandled %d\n", __func__, request));
294 		return;
295 	}
296 
297 	xs = arg;
298 	periph = xs->xs_periph;
299 
300 	/*
301 	 * This can happen when we run out of queue slots.
302 	 */
303 	vr = vioscsi_req_get(sc);
304 	if (vr == NULL) {
305 		xs->error = XS_BUSY;
306 		scsipi_done(xs);
307 		return;
308 	}
309 
310 	req = &vr->vr_req;
311 	slot = vr - sc->sc_reqs;
312 
313 	/*
314 	 * "The only supported format for the LUN field is: first byte set to
315 	 * 1, second byte set to target, third and fourth byte representing a
316 	 * single level LUN structure, followed by four zero bytes."
317 	 */
318 	if (periph->periph_target >= 256 || periph->periph_lun >= 16384
319 	    || periph->periph_target < 0 || periph->periph_lun < 0) {
320 		goto stuffup;
321 	}
322 
323 	req->lun[0] = 1;
324 	req->lun[1] = periph->periph_target;
325 	req->lun[2] = 0x40 | ((periph->periph_lun >> 8) & 0x3F);
326 	req->lun[3] = periph->periph_lun & 0xFF;
327 	memset(req->lun + 4, 0, 4);
328 	DPRINTF(("%s: command %p for %d:%d at slot %d\n", __func__,
329 	    xs, periph->periph_target, periph->periph_lun, slot));
330 
331 	/* tag */
332 	switch (XS_CTL_TAGTYPE(xs)) {
333 	case XS_CTL_HEAD_TAG:
334 		req->task_attr = VIRTIO_SCSI_S_HEAD;
335 		break;
336 
337 #if 0	/* XXX */
338 	case XS_CTL_ACA_TAG:
339 		req->task_attr = VIRTIO_SCSI_S_ACA;
340 		break;
341 #endif
342 
343 	case XS_CTL_ORDERED_TAG:
344 		req->task_attr = VIRTIO_SCSI_S_ORDERED;
345 		break;
346 
347 	case XS_CTL_SIMPLE_TAG:
348 	default:
349 		req->task_attr = VIRTIO_SCSI_S_SIMPLE;
350 		break;
351 	}
352 	req->id = virtio_rw64(vsc, slot);
353 
354 	if ((size_t)xs->cmdlen > sizeof(req->cdb)) {
355 		DPRINTF(("%s: bad cmdlen %zu > %zu\n", __func__,
356 		    (size_t)xs->cmdlen, sizeof(req->cdb)));
357 		goto stuffup;
358 	}
359 
360 	memset(req->cdb, 0, sizeof(req->cdb));
361 	memcpy(req->cdb, xs->cmd, xs->cmdlen);
362 
363 	error = bus_dmamap_load(virtio_dmat(vsc), vr->vr_data,
364 	    xs->data, xs->datalen, NULL, XS2DMA(xs));
365 	if (error) {
366 		aprint_error_dev(sc->sc_dev, "%s: error %d loading DMA map\n",
367 		    __func__, error);
368 
369 		if (error == ENOMEM || error == EAGAIN) {
370 			/*
371 			 * Map is allocated with ALLOCNOW, so this should
372 			 * actually never ever happen.
373 			 */
374 			xs->error = XS_RESOURCE_SHORTAGE;
375 		} else {
376 stuffup:
377 			/* not a temporary condition */
378 			xs->error = XS_DRIVER_STUFFUP;
379 		}
380 
381 		virtio_enqueue_abort(vsc, vq, slot);
382 		scsipi_done(xs);
383 		return;
384 	}
385 
386 	int nsegs = VIRTIO_SCSI_MIN_SEGMENTS;
387 	if ((xs->xs_control & (XS_CTL_DATA_IN|XS_CTL_DATA_OUT)) != 0)
388 		nsegs += vr->vr_data->dm_nsegs;
389 
390 	error = virtio_enqueue_reserve(vsc, vq, slot, nsegs);
391 	if (error) {
392 		bus_dmamap_unload(virtio_dmat(vsc), vr->vr_data);
393 		/* slot already freed by virtio_enqueue_reserve() */
394 		xs->error = XS_BUSY;
395 		scsipi_done(xs);
396 		return;
397 	}
398 
399 	vr->vr_xs = xs;
400 
401 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
402 	    offsetof(struct vioscsi_req, vr_req),
403 	    sizeof(struct virtio_scsi_req_hdr),
404 	    BUS_DMASYNC_PREWRITE);
405 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
406 	    offsetof(struct vioscsi_req, vr_res),
407             sizeof(struct virtio_scsi_res_hdr),
408 	    BUS_DMASYNC_PREREAD);
409 	if ((xs->xs_control & (XS_CTL_DATA_IN|XS_CTL_DATA_OUT)) != 0)
410 		bus_dmamap_sync(virtio_dmat(vsc), vr->vr_data, 0, xs->datalen,
411 		    XS2DMAPRE(xs));
412 
413 	virtio_enqueue_p(vsc, vq, slot, vr->vr_control,
414 	    offsetof(struct vioscsi_req, vr_req),
415             sizeof(struct virtio_scsi_req_hdr), 1);
416 	if (xs->xs_control & XS_CTL_DATA_OUT)
417 		virtio_enqueue(vsc, vq, slot, vr->vr_data, 1);
418 	virtio_enqueue_p(vsc, vq, slot, vr->vr_control,
419 	    offsetof(struct vioscsi_req, vr_res),
420             sizeof(struct virtio_scsi_res_hdr), 0);
421 	if (xs->xs_control & XS_CTL_DATA_IN)
422 		virtio_enqueue(vsc, vq, slot, vr->vr_data, 0);
423 	dopoll = (xs->xs_control & XS_CTL_POLL) != 0;
424 	virtio_enqueue_commit(vsc, vq, slot, 1);
425 
426 	if (!dopoll)
427 		return;
428 
429 	DPRINTF(("%s: polling...\n", __func__));
430 	// XXX: do this better.
431 	int timeout = 1000;
432 	do {
433 		virtio_intrhand(vsc);
434 		if (vr->vr_xs != xs)
435 			break;
436 		delay(1000);
437 	} while (--timeout > 0);
438 
439 	if (vr->vr_xs == xs) {
440 		// XXX: Abort!
441 		xs->error = XS_TIMEOUT;
442 		xs->resid = xs->datalen;
443 		DPRINTF(("%s: polling timeout\n", __func__));
444 		scsipi_done(xs);
445 	}
446 	DPRINTF(("%s: command %p done (timeout=%d)\n", __func__,
447 	    xs, timeout));
448 }
449 
450 static void
vioscsi_req_done(struct vioscsi_softc * sc,struct virtio_softc * vsc,struct vioscsi_req * vr,struct virtqueue * vq,int slot)451 vioscsi_req_done(struct vioscsi_softc *sc, struct virtio_softc *vsc,
452     struct vioscsi_req *vr, struct virtqueue *vq, int slot)
453 {
454 	struct scsipi_xfer *xs = vr->vr_xs;
455 	size_t sense_len;
456 
457 	DPRINTF(("%s: enter\n", __func__));
458 
459 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
460 	    offsetof(struct vioscsi_req, vr_req),
461 	    sizeof(struct virtio_scsi_req_hdr),
462 	    BUS_DMASYNC_POSTWRITE);
463 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
464 	    offsetof(struct vioscsi_req, vr_res),
465 	    sizeof(struct virtio_scsi_res_hdr),
466 	    BUS_DMASYNC_POSTREAD);
467 	if (xs->datalen)
468 		bus_dmamap_sync(virtio_dmat(vsc), vr->vr_data, 0, xs->datalen,
469 		    XS2DMAPOST(xs));
470 
471 	xs->status = vr->vr_res.status;
472 	xs->resid  = virtio_rw32(vsc, vr->vr_res.residual);
473 
474 	switch (vr->vr_res.response) {
475 	case VIRTIO_SCSI_S_OK:
476 		sense_len = MIN(sizeof(xs->sense),
477 				virtio_rw32(vsc, vr->vr_res.sense_len));
478 		memcpy(&xs->sense, vr->vr_res.sense, sense_len);
479 		xs->error = (sense_len == 0) ? XS_NOERROR : XS_SENSE;
480 		break;
481 	case VIRTIO_SCSI_S_BAD_TARGET:
482 		vioscsi_bad_target(xs);
483 		break;
484 	default:
485 		DPRINTF(("%s: stuffup: %d\n", __func__, vr->vr_res.response));
486 		xs->error = XS_DRIVER_STUFFUP;
487 		xs->resid = xs->datalen;
488 		break;
489 	}
490 
491 	DPRINTF(("%s: command %p done %d, %d, %d\n", __func__,
492 	    xs, xs->error, xs->status, xs->resid));
493 
494 	bus_dmamap_unload(virtio_dmat(vsc), vr->vr_data);
495 	vr->vr_xs = NULL;
496 
497 	virtio_dequeue_commit(vsc, vq, slot);
498 
499 	mutex_exit(&sc->sc_mutex);
500 	scsipi_done(xs);
501 	mutex_enter(&sc->sc_mutex);
502 }
503 
504 static void
vioscsi_bad_target(struct scsipi_xfer * xs)505 vioscsi_bad_target(struct scsipi_xfer *xs)
506 {
507 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
508 
509 	DPRINTF(("%s: bad target %d:%d\n", __func__,
510 	    xs->xs_periph->periph_target, xs->xs_periph->periph_lun));
511 
512 	memset(sense, 0, sizeof(*sense));
513 	sense->response_code = 0x70;
514 	sense->flags = SKEY_ILLEGAL_REQUEST;
515 	xs->error = XS_SENSE;
516 	xs->status = 0;
517 	xs->resid = 0;
518 }
519 
520 static int
vioscsi_vq_done(struct virtqueue * vq)521 vioscsi_vq_done(struct virtqueue *vq)
522 {
523 	struct virtio_softc *vsc = vq->vq_owner;
524 	struct vioscsi_softc *sc = device_private(virtio_child(vsc));
525 	int ret = 0;
526 
527 	DPRINTF(("%s: enter %d\n", __func__, vq->vq_index));
528 
529 	mutex_enter(&sc->sc_mutex);
530 
531 	for (;;) {
532 		int r, slot;
533 
534 		r = virtio_dequeue(vsc, vq, &slot, NULL);
535 		if (r != 0)
536 			break;
537 
538 		DPRINTF(("%s: slot=%d\n", __func__, slot));
539 
540 		vioscsi_req_done(sc, vsc, &sc->sc_reqs[slot], vq, slot);
541 
542 		ret = 1;
543 	}
544 
545 	mutex_exit(&sc->sc_mutex);
546 
547 	DPRINTF(("%s: exit %d: %d\n", __func__, vq->vq_index, ret));
548 
549 	return ret;
550 }
551 
552 static struct vioscsi_req *
vioscsi_req_get(struct vioscsi_softc * sc)553 vioscsi_req_get(struct vioscsi_softc *sc)
554 {
555 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
556 	struct virtqueue *vq = &sc->sc_vqs[VIOSCSI_VQ_REQUEST];
557 	struct vioscsi_req *vr = NULL;
558 	int r, slot;
559 
560 	mutex_enter(&sc->sc_mutex);
561 
562 	if ((r = virtio_enqueue_prep(vsc, vq, &slot)) != 0) {
563 		DPRINTF(("%s: virtio_enqueue_get error %d\n", __func__, r));
564 		goto out;
565 	}
566 	KASSERT(slot < sc->sc_nreqs);
567 	vr = &sc->sc_reqs[slot];
568 
569 	DPRINTF(("%s: %p, %d\n", __func__, vr, slot));
570 
571 out:
572 	mutex_exit(&sc->sc_mutex);
573 
574 	return vr;
575 }
576 
577 static int
vioscsi_alloc_reqs(struct vioscsi_softc * sc,struct virtio_softc * vsc,int qsize)578 vioscsi_alloc_reqs(struct vioscsi_softc *sc, struct virtio_softc *vsc,
579     int qsize)
580 {
581 	size_t allocsize;
582 	int r, rsegs, slot;
583 	void *vaddr;
584 	struct vioscsi_req *vr;
585 
586 	allocsize = qsize * sizeof(struct vioscsi_req);
587 	r = bus_dmamem_alloc(virtio_dmat(vsc), allocsize, 0, 0,
588 	    &sc->sc_reqs_segs[0], 1, &rsegs, BUS_DMA_NOWAIT);
589 	if (r != 0) {
590 		aprint_error_dev(sc->sc_dev,
591 		    "%s: bus_dmamem_alloc, size %zu, error %d\n", __func__,
592 		    allocsize, r);
593 		return r;
594 	}
595 	r = bus_dmamem_map(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1,
596 	    allocsize, &vaddr, BUS_DMA_NOWAIT);
597 	if (r != 0) {
598 		aprint_error_dev(sc->sc_dev,
599 		    "%s: bus_dmamem_map failed, error %d\n", __func__, r);
600 		bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
601 		return r;
602 	}
603 	memset(vaddr, 0, allocsize);
604 
605 	sc->sc_reqs = vaddr;
606 	sc->sc_nreqs = qsize;
607 
608 	/* Prepare maps for the requests */
609 	for (slot=0; slot < qsize; slot++) {
610 		vr = &sc->sc_reqs[slot];
611 
612 		r = bus_dmamap_create(virtio_dmat(vsc),
613 		    offsetof(struct vioscsi_req, vr_xs), 1,
614 		    offsetof(struct vioscsi_req, vr_xs), 0,
615 		    BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &vr->vr_control);
616 		if (r != 0) {
617 			aprint_error_dev(sc->sc_dev,
618 		    	    "%s: bus_dmamap_create ctrl failed, error %d\n",
619 			    __func__, r);
620 			goto cleanup;
621 		}
622 
623 		r = bus_dmamap_create(virtio_dmat(vsc), MAXPHYS, sc->sc_seg_max,
624 		    MAXPHYS, 0, BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &vr->vr_data);
625 		if (r != 0) {
626 			aprint_error_dev(sc->sc_dev,
627 		    	    "%s: bus_dmamap_create data failed, error %d\n",
628 			    __func__, r);
629 			goto cleanup;
630 		}
631 
632 		r = bus_dmamap_load(virtio_dmat(vsc), vr->vr_control,
633 		    vr, offsetof(struct vioscsi_req, vr_xs), NULL,
634 		    BUS_DMA_NOWAIT);
635 		if (r != 0) {
636 			aprint_error_dev(sc->sc_dev,
637 		    	    "%s: bus_dmamap_load ctrl error %d\n",
638 			    __func__, r);
639 			goto cleanup;
640 		}
641 	}
642 
643 	return 0;
644 
645 cleanup:
646 	for (; slot > 0; slot--) {
647 		vr = &sc->sc_reqs[slot];
648 
649 		if (vr->vr_control) {
650 			/* this will also unload the mapping if loaded */
651 			bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_control);
652 			vr->vr_control = NULL;
653 		}
654 
655 		if (vr->vr_data) {
656 			bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_data);
657 			vr->vr_data = NULL;
658 		}
659 	}
660 
661 	bus_dmamem_unmap(virtio_dmat(vsc), vaddr, allocsize);
662 	bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
663 
664 	return r;
665 }
666 
667 static void
vioscsi_free_reqs(struct vioscsi_softc * sc,struct virtio_softc * vsc)668 vioscsi_free_reqs(struct vioscsi_softc *sc, struct virtio_softc *vsc)
669 {
670 	int slot;
671 	struct vioscsi_req *vr;
672 
673 	if (sc->sc_nreqs == 0) {
674 		/* Not allocated */
675 		return;
676 	}
677 
678 	/* Free request maps */
679 	for (slot=0; slot < sc->sc_nreqs; slot++) {
680 		vr = &sc->sc_reqs[slot];
681 
682 		bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_control);
683 		bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_data);
684 	}
685 
686 	bus_dmamem_unmap(virtio_dmat(vsc), sc->sc_reqs,
687 			 sc->sc_nreqs * sizeof(struct vioscsi_req));
688 	bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
689 }
690 
691 MODULE(MODULE_CLASS_DRIVER, vioscsi, "virtio");
692 
693 #ifdef _MODULE
694 #include "ioconf.c"
695 #endif
696 
697 static int
vioscsi_modcmd(modcmd_t cmd,void * opaque)698 vioscsi_modcmd(modcmd_t cmd, void *opaque)
699 {
700         int error = 0;
701 
702 #ifdef _MODULE
703         switch (cmd) {
704         case MODULE_CMD_INIT:
705                 error = config_init_component(cfdriver_ioconf_vioscsi,
706                     cfattach_ioconf_vioscsi, cfdata_ioconf_vioscsi);
707                 break;
708         case MODULE_CMD_FINI:
709                 error = config_fini_component(cfdriver_ioconf_vioscsi,
710                     cfattach_ioconf_vioscsi, cfdata_ioconf_vioscsi);
711                 break;
712         default:
713                 error = ENOTTY;
714                 break;
715         }
716 #endif
717 
718         return error;
719 }
720