xref: /netbsd-src/sys/dev/pci/vioscsi.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: vioscsi.c,v 1.25 2021/01/20 19:46:48 reinoud 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 1.25 2021/01/20 19:46:48 reinoud 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
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
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, sc->sc_vqs,
132 	    NULL, virtio_vq_intr, VIRTIO_F_INTR_MSIX,
133 	    0, VIRTIO_COMMON_FLAG_BITS);
134 
135 	mutex_init(&sc->sc_mutex, MUTEX_DEFAULT, ipl);
136 
137 	uint32_t cmd_per_lun = virtio_read_device_config_4(vsc,
138 	    VIRTIO_SCSI_CONFIG_CMD_PER_LUN);
139 
140 	uint32_t seg_max = virtio_read_device_config_4(vsc,
141 	    VIRTIO_SCSI_CONFIG_SEG_MAX);
142 
143 	uint16_t max_target = virtio_read_device_config_2(vsc,
144 	    VIRTIO_SCSI_CONFIG_MAX_TARGET);
145 
146 	uint32_t max_lun = virtio_read_device_config_4(vsc,
147 	    VIRTIO_SCSI_CONFIG_MAX_LUN);
148 
149 	sc->sc_seg_max = seg_max;
150 
151 	for(i=0; i < __arraycount(sc->sc_vqs); i++) {
152 		rv = virtio_alloc_vq(vsc, &sc->sc_vqs[i], i, MAXPHYS,
153 		    VIRTIO_SCSI_MIN_SEGMENTS + howmany(MAXPHYS, NBPG),
154 		    vioscsi_vq_names[i]);
155 		if (rv) {
156 			aprint_error_dev(sc->sc_dev,
157 			    "failed to allocate virtqueue %d\n", i);
158 			goto err;
159 		}
160 
161 		if (i == VIOSCSI_VQ_REQUEST)
162 			sc->sc_vqs[i].vq_done = vioscsi_vq_done;
163 	}
164 
165 	qsize = sc->sc_vqs[VIOSCSI_VQ_REQUEST].vq_num;
166 	if (vioscsi_alloc_reqs(sc, vsc, qsize))
167 		goto err;
168 
169 	aprint_normal_dev(sc->sc_dev,
170 	    "cmd_per_lun %u qsize %d seg_max %u max_target %hu"
171 	    " max_lun %u\n",
172 	    cmd_per_lun, qsize, seg_max, max_target, max_lun);
173 
174 	if (virtio_child_attach_finish(vsc) != 0)
175 		goto err;
176 
177 	/*
178 	 * Fill in the scsipi_adapter.
179 	 */
180 	memset(adapt, 0, sizeof(*adapt));
181 	adapt->adapt_dev = sc->sc_dev;
182 	adapt->adapt_nchannels = 1;
183 	adapt->adapt_openings = MIN(qsize, cmd_per_lun);
184 	adapt->adapt_max_periph = adapt->adapt_openings;
185 	adapt->adapt_request = vioscsi_scsipi_request;
186 	adapt->adapt_minphys = minphys;
187 
188 	/*
189 	 * Fill in the scsipi_channel.
190 	 */
191 	memset(chan, 0, sizeof(*chan));
192 	chan->chan_adapter = adapt;
193 	chan->chan_bustype = &scsi_bustype;
194 	chan->chan_channel = 0;
195 	chan->chan_ntargets = MIN(max_target, 16);	/* cap reasonably */
196 	chan->chan_nluns = MIN(max_lun, 1024);		/* cap reasonably */
197 	chan->chan_id = max_target;
198 	chan->chan_flags = SCSIPI_CHAN_NOSETTLE;
199 	/*
200 	 * XXX Remove this when scsipi is REPORT LUNS-aware.
201 	 * scsipi(4) insists that LUNs must be contiguous starting from 0.
202 	 * This is not true on Linode (circa 2020).
203 	 *
204 	 * Also if explicitly selecting the 'Virtio SCSI Single'
205 	 * controller (which is not the default SCSI controller) on
206 	 * Proxmox hosts, each disk will be on its own scsi bus at
207 	 * target 0 but unexpectedly on a LUN matching the drive number
208 	 * on the system (i.e. drive 0 will be bus 0, target 0, lun
209 	 * 0; drive 1 will be bus 1, target 0, lun 1, drive 2 will be
210 	 * bus 2, target 0, lun 2 -- which is where the gaps start
211 	 * happening). https://bugzilla.proxmox.com/show_bug.cgi?id=2985
212 	 */
213 	chan->chan_defquirks = PQUIRK_FORCELUNS;
214 
215 	config_found(self, &sc->sc_channel, scsiprint);
216 	return;
217 
218 err:
219 	if (qsize > 0)
220 		vioscsi_free_reqs(sc, vsc);
221 
222 	for (i=0; i < __arraycount(sc->sc_vqs); i++) {
223 		if (sc->sc_vqs[i].vq_num > 0)
224 			virtio_free_vq(vsc, &sc->sc_vqs[i]);
225 	}
226 
227 	virtio_child_attach_failed(vsc);
228 }
229 
230 static int
231 vioscsi_detach(device_t self, int flags)
232 {
233 	struct vioscsi_softc *sc = device_private(self);
234 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
235 	int rc, i;
236 
237 	/*
238 	 * Dequeue all pending finished requests. Must be done
239 	 * before we try to detach children so that we process
240 	 * their pending requests while they still exist.
241 	 */
242 	if (sc->sc_vqs[VIOSCSI_VQ_REQUEST].vq_num > 0)
243 		vioscsi_vq_done(&sc->sc_vqs[VIOSCSI_VQ_REQUEST]);
244 
245 	if ((rc = config_detach_children(self, flags)) != 0)
246 		return rc;
247 
248 	virtio_reset(vsc);
249 
250 	for (i = 0; i < __arraycount(sc->sc_vqs); i++) {
251 		if (sc->sc_vqs[i].vq_num > 0)
252 			virtio_free_vq(vsc, &sc->sc_vqs[i]);
253 	}
254 
255 	vioscsi_free_reqs(sc, vsc);
256 
257 	virtio_child_detach(vsc);
258 
259 	mutex_destroy(&sc->sc_mutex);
260 
261 	return 0;
262 }
263 
264 #define XS2DMA(xs) \
265     ((((xs)->xs_control & XS_CTL_DATA_IN) ? BUS_DMA_READ : BUS_DMA_WRITE) | \
266     (((xs)->xs_control & XS_CTL_NOSLEEP) ? BUS_DMA_NOWAIT : BUS_DMA_WAITOK) | \
267     BUS_DMA_STREAMING)
268 
269 #define XS2DMAPRE(xs) (((xs)->xs_control & XS_CTL_DATA_IN) ? \
270     BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE)
271 
272 #define XS2DMAPOST(xs) (((xs)->xs_control & XS_CTL_DATA_IN) ? \
273     BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE)
274 
275 static void
276 vioscsi_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t
277     request, void *arg)
278 {
279 	struct vioscsi_softc *sc =
280 	    device_private(chan->chan_adapter->adapt_dev);
281 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
282 	struct scsipi_xfer *xs;
283 	struct scsipi_periph *periph;
284 	struct vioscsi_req *vr;
285 	struct virtio_scsi_req_hdr *req;
286 	struct virtqueue *vq = &sc->sc_vqs[VIOSCSI_VQ_REQUEST];
287 	int slot, error;
288 	bool dopoll;
289 
290 	DPRINTF(("%s: enter\n", __func__));
291 
292 	switch (request) {
293 	case ADAPTER_REQ_RUN_XFER:
294 		break;
295 	case ADAPTER_REQ_SET_XFER_MODE:
296 	{
297 		struct scsipi_xfer_mode *xm = arg;
298 		xm->xm_mode = PERIPH_CAP_TQING;
299 		xm->xm_period = 0;
300 		xm->xm_offset = 0;
301 		scsipi_async_event(chan, ASYNC_EVENT_XFER_MODE, xm);
302 		return;
303 	}
304 	default:
305 		DPRINTF(("%s: unhandled %d\n", __func__, request));
306 		return;
307 	}
308 
309 	xs = arg;
310 	periph = xs->xs_periph;
311 
312 	/*
313 	 * This can happen when we run out of queue slots.
314 	 */
315 	vr = vioscsi_req_get(sc);
316 	if (vr == NULL) {
317 		xs->error = XS_RESOURCE_SHORTAGE;
318 		scsipi_done(xs);
319 		return;
320 	}
321 
322 	req = &vr->vr_req;
323 	slot = vr - sc->sc_reqs;
324 
325 	/*
326 	 * "The only supported format for the LUN field is: first byte set to
327 	 * 1, second byte set to target, third and fourth byte representing a
328 	 * single level LUN structure, followed by four zero bytes."
329 	 */
330 	if (periph->periph_target >= 256 || periph->periph_lun >= 16384
331 	    || periph->periph_target < 0 || periph->periph_lun < 0) {
332 		goto stuffup;
333 	}
334 
335 	req->lun[0] = 1;
336 	req->lun[1] = periph->periph_target;
337 	req->lun[2] = 0x40 | ((periph->periph_lun >> 8) & 0x3F);
338 	req->lun[3] = periph->periph_lun & 0xFF;
339 	memset(req->lun + 4, 0, 4);
340 	DPRINTF(("%s: command %p for %d:%d at slot %d\n", __func__,
341 	    xs, periph->periph_target, periph->periph_lun, slot));
342 
343 	/* tag */
344 	switch (XS_CTL_TAGTYPE(xs)) {
345 	case XS_CTL_HEAD_TAG:
346 		req->task_attr = VIRTIO_SCSI_S_HEAD;
347 		break;
348 
349 #if 0	/* XXX */
350 	case XS_CTL_ACA_TAG:
351 		req->task_attr = VIRTIO_SCSI_S_ACA;
352 		break;
353 #endif
354 
355 	case XS_CTL_ORDERED_TAG:
356 		req->task_attr = VIRTIO_SCSI_S_ORDERED;
357 		break;
358 
359 	case XS_CTL_SIMPLE_TAG:
360 	default:
361 		req->task_attr = VIRTIO_SCSI_S_SIMPLE;
362 		break;
363 	}
364 	req->id = virtio_rw64(vsc, slot);
365 
366 	if ((size_t)xs->cmdlen > sizeof(req->cdb)) {
367 		DPRINTF(("%s: bad cmdlen %zu > %zu\n", __func__,
368 		    (size_t)xs->cmdlen, sizeof(req->cdb)));
369 		goto stuffup;
370 	}
371 
372 	memset(req->cdb, 0, sizeof(req->cdb));
373 	memcpy(req->cdb, xs->cmd, xs->cmdlen);
374 
375 	error = bus_dmamap_load(virtio_dmat(vsc), vr->vr_data,
376 	    xs->data, xs->datalen, NULL, XS2DMA(xs));
377 	if (error) {
378 		aprint_error_dev(sc->sc_dev, "%s: error %d loading DMA map\n",
379 		    __func__, error);
380 
381 		if (error == ENOMEM || error == EAGAIN) {
382 			/*
383 			 * Map is allocated with ALLOCNOW, so this should
384 			 * actually never ever happen.
385 			 */
386 			xs->error = XS_RESOURCE_SHORTAGE;
387 		} else {
388 stuffup:
389 			/* not a temporary condition */
390 			xs->error = XS_DRIVER_STUFFUP;
391 		}
392 
393 		virtio_enqueue_abort(vsc, vq, slot);
394 		scsipi_done(xs);
395 		return;
396 	}
397 
398 	int nsegs = VIRTIO_SCSI_MIN_SEGMENTS;
399 	if ((xs->xs_control & (XS_CTL_DATA_IN|XS_CTL_DATA_OUT)) != 0)
400 		nsegs += vr->vr_data->dm_nsegs;
401 
402 	error = virtio_enqueue_reserve(vsc, vq, slot, nsegs);
403 	if (error) {
404 		aprint_error_dev(sc->sc_dev, "error reserving %d (nsegs %d)\n",
405 		    error, nsegs);
406 		bus_dmamap_unload(virtio_dmat(vsc), vr->vr_data);
407 		/* slot already freed by virtio_enqueue_reserve() */
408 		xs->error = XS_RESOURCE_SHORTAGE;
409 		scsipi_done(xs);
410 		return;
411 	}
412 
413 	vr->vr_xs = xs;
414 
415 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
416 	    offsetof(struct vioscsi_req, vr_req),
417 	    sizeof(struct virtio_scsi_req_hdr),
418 	    BUS_DMASYNC_PREWRITE);
419 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
420 	    offsetof(struct vioscsi_req, vr_res),
421             sizeof(struct virtio_scsi_res_hdr),
422 	    BUS_DMASYNC_PREREAD);
423 	if ((xs->xs_control & (XS_CTL_DATA_IN|XS_CTL_DATA_OUT)) != 0)
424 		bus_dmamap_sync(virtio_dmat(vsc), vr->vr_data, 0, xs->datalen,
425 		    XS2DMAPRE(xs));
426 
427 	virtio_enqueue_p(vsc, vq, slot, vr->vr_control,
428 	    offsetof(struct vioscsi_req, vr_req),
429             sizeof(struct virtio_scsi_req_hdr), 1);
430 	if (xs->xs_control & XS_CTL_DATA_OUT)
431 		virtio_enqueue(vsc, vq, slot, vr->vr_data, 1);
432 	virtio_enqueue_p(vsc, vq, slot, vr->vr_control,
433 	    offsetof(struct vioscsi_req, vr_res),
434             sizeof(struct virtio_scsi_res_hdr), 0);
435 	if (xs->xs_control & XS_CTL_DATA_IN)
436 		virtio_enqueue(vsc, vq, slot, vr->vr_data, 0);
437 	dopoll = (xs->xs_control & XS_CTL_POLL) != 0;
438 	virtio_enqueue_commit(vsc, vq, slot, 1);
439 
440 	if (!dopoll)
441 		return;
442 
443 	DPRINTF(("%s: polling...\n", __func__));
444 	// XXX: do this better.
445 	int timeout = 1000;
446 	do {
447 		virtio_intrhand(vsc);
448 		if (vr->vr_xs != xs)
449 			break;
450 		delay(1000);
451 	} while (--timeout > 0);
452 
453 	if (vr->vr_xs == xs) {
454 		// XXX: Abort!
455 		xs->error = XS_TIMEOUT;
456 		xs->resid = xs->datalen;
457 		DPRINTF(("%s: polling timeout\n", __func__));
458 		scsipi_done(xs);
459 	}
460 	DPRINTF(("%s: command %p done (timeout=%d)\n", __func__,
461 	    xs, timeout));
462 }
463 
464 static void
465 vioscsi_req_done(struct vioscsi_softc *sc, struct virtio_softc *vsc,
466     struct vioscsi_req *vr, struct virtqueue *vq, int slot)
467 {
468 	struct scsipi_xfer *xs = vr->vr_xs;
469 	size_t sense_len;
470 
471 	DPRINTF(("%s: enter\n", __func__));
472 
473 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
474 	    offsetof(struct vioscsi_req, vr_req),
475 	    sizeof(struct virtio_scsi_req_hdr),
476 	    BUS_DMASYNC_POSTWRITE);
477 	bus_dmamap_sync(virtio_dmat(vsc), vr->vr_control,
478 	    offsetof(struct vioscsi_req, vr_res),
479 	    sizeof(struct virtio_scsi_res_hdr),
480 	    BUS_DMASYNC_POSTREAD);
481 	if (xs->datalen)
482 		bus_dmamap_sync(virtio_dmat(vsc), vr->vr_data, 0, xs->datalen,
483 		    XS2DMAPOST(xs));
484 
485 	xs->status = vr->vr_res.status;
486 	xs->resid  = virtio_rw32(vsc, vr->vr_res.residual);
487 
488 	switch (vr->vr_res.response) {
489 	case VIRTIO_SCSI_S_OK:
490 		sense_len = MIN(sizeof(xs->sense),
491 				virtio_rw32(vsc, vr->vr_res.sense_len));
492 		memcpy(&xs->sense, vr->vr_res.sense, sense_len);
493 		xs->error = (sense_len == 0) ? XS_NOERROR : XS_SENSE;
494 		break;
495 	case VIRTIO_SCSI_S_BAD_TARGET:
496 		vioscsi_bad_target(xs);
497 		break;
498 	default:
499 		DPRINTF(("%s: stuffup: %d\n", __func__, vr->vr_res.response));
500 		xs->error = XS_DRIVER_STUFFUP;
501 		xs->resid = xs->datalen;
502 		break;
503 	}
504 
505 	DPRINTF(("%s: command %p done %d, %d, %d\n", __func__,
506 	    xs, xs->error, xs->status, xs->resid));
507 
508 	bus_dmamap_unload(virtio_dmat(vsc), vr->vr_data);
509 	vr->vr_xs = NULL;
510 
511 	virtio_dequeue_commit(vsc, vq, slot);
512 
513 	mutex_exit(&sc->sc_mutex);
514 	scsipi_done(xs);
515 	mutex_enter(&sc->sc_mutex);
516 }
517 
518 static void
519 vioscsi_bad_target(struct scsipi_xfer *xs)
520 {
521 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
522 
523 	DPRINTF(("%s: bad target %d:%d\n", __func__,
524 	    xs->xs_periph->periph_target, xs->xs_periph->periph_lun));
525 
526 	memset(sense, 0, sizeof(*sense));
527 	sense->response_code = 0x70;
528 	sense->flags = SKEY_ILLEGAL_REQUEST;
529 	xs->error = XS_SENSE;
530 	xs->status = 0;
531 	xs->resid = 0;
532 }
533 
534 static int
535 vioscsi_vq_done(struct virtqueue *vq)
536 {
537 	struct virtio_softc *vsc = vq->vq_owner;
538 	struct vioscsi_softc *sc = device_private(virtio_child(vsc));
539 	int ret = 0;
540 
541 	DPRINTF(("%s: enter %d\n", __func__, vq->vq_index));
542 
543 	mutex_enter(&sc->sc_mutex);
544 
545 	for (;;) {
546 		int r, slot;
547 
548 		r = virtio_dequeue(vsc, vq, &slot, NULL);
549 		if (r != 0)
550 			break;
551 
552 		DPRINTF(("%s: slot=%d\n", __func__, slot));
553 
554 		vioscsi_req_done(sc, vsc, &sc->sc_reqs[slot], vq, slot);
555 
556 		ret = 1;
557 	}
558 
559 	mutex_exit(&sc->sc_mutex);
560 
561 	DPRINTF(("%s: exit %d: %d\n", __func__, vq->vq_index, ret));
562 
563 	return ret;
564 }
565 
566 static struct vioscsi_req *
567 vioscsi_req_get(struct vioscsi_softc *sc)
568 {
569 	struct virtio_softc *vsc = device_private(device_parent(sc->sc_dev));
570 	struct virtqueue *vq = &sc->sc_vqs[VIOSCSI_VQ_REQUEST];
571 	struct vioscsi_req *vr = NULL;
572 	int r, slot;
573 
574 	mutex_enter(&sc->sc_mutex);
575 
576 	if ((r = virtio_enqueue_prep(vsc, vq, &slot)) != 0) {
577 		DPRINTF(("%s: virtio_enqueue_get error %d\n", __func__, r));
578 		goto out;
579 	}
580 	KASSERT(slot < sc->sc_nreqs);
581 	vr = &sc->sc_reqs[slot];
582 
583 	DPRINTF(("%s: %p, %d\n", __func__, vr, slot));
584 
585 out:
586 	mutex_exit(&sc->sc_mutex);
587 
588 	return vr;
589 }
590 
591 static int
592 vioscsi_alloc_reqs(struct vioscsi_softc *sc, struct virtio_softc *vsc,
593     int qsize)
594 {
595 	size_t allocsize;
596 	int r, rsegs, slot;
597 	void *vaddr;
598 	struct vioscsi_req *vr;
599 
600 	allocsize = qsize * sizeof(struct vioscsi_req);
601 	r = bus_dmamem_alloc(virtio_dmat(vsc), allocsize, 0, 0,
602 	    &sc->sc_reqs_segs[0], 1, &rsegs, BUS_DMA_NOWAIT);
603 	if (r != 0) {
604 		aprint_error_dev(sc->sc_dev,
605 		    "%s: bus_dmamem_alloc, size %zu, error %d\n", __func__,
606 		    allocsize, r);
607 		return r;
608 	}
609 	r = bus_dmamem_map(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1,
610 	    allocsize, &vaddr, BUS_DMA_NOWAIT);
611 	if (r != 0) {
612 		aprint_error_dev(sc->sc_dev,
613 		    "%s: bus_dmamem_map failed, error %d\n", __func__, r);
614 		bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
615 		return r;
616 	}
617 	memset(vaddr, 0, allocsize);
618 
619 	sc->sc_reqs = vaddr;
620 	sc->sc_nreqs = qsize;
621 
622 	/* Prepare maps for the requests */
623 	for (slot=0; slot < qsize; slot++) {
624 		vr = &sc->sc_reqs[slot];
625 
626 		r = bus_dmamap_create(virtio_dmat(vsc),
627 		    offsetof(struct vioscsi_req, vr_xs), 1,
628 		    offsetof(struct vioscsi_req, vr_xs), 0,
629 		    BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &vr->vr_control);
630 		if (r != 0) {
631 			aprint_error_dev(sc->sc_dev,
632 		    	    "%s: bus_dmamem_create ctrl failed, error %d\n",
633 			    __func__, r);
634 			goto cleanup;
635 		}
636 
637 		r = bus_dmamap_create(virtio_dmat(vsc), MAXPHYS, sc->sc_seg_max,
638 		    MAXPHYS, 0, BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &vr->vr_data);
639 		if (r != 0) {
640 			aprint_error_dev(sc->sc_dev,
641 		    	    "%s: bus_dmamem_create data failed, error %d\n",
642 			    __func__, r);
643 			goto cleanup;
644 		}
645 
646 		r = bus_dmamap_load(virtio_dmat(vsc), vr->vr_control,
647 		    vr, offsetof(struct vioscsi_req, vr_xs), NULL,
648 		    BUS_DMA_NOWAIT);
649 		if (r != 0) {
650 			aprint_error_dev(sc->sc_dev,
651 		    	    "%s: bus_dmamap_load ctrl error %d\n",
652 			    __func__, r);
653 			goto cleanup;
654 		}
655 	}
656 
657 	return 0;
658 
659 cleanup:
660 	for (; slot > 0; slot--) {
661 		vr = &sc->sc_reqs[slot];
662 
663 		if (vr->vr_control) {
664 			/* this will also unload the mapping if loaded */
665 			bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_control);
666 			vr->vr_control = NULL;
667 		}
668 
669 		if (vr->vr_data) {
670 			bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_data);
671 			vr->vr_data = NULL;
672 		}
673 	}
674 
675 	bus_dmamem_unmap(virtio_dmat(vsc), vaddr, allocsize);
676 	bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
677 
678 	return r;
679 }
680 
681 static void
682 vioscsi_free_reqs(struct vioscsi_softc *sc, struct virtio_softc *vsc)
683 {
684 	int slot;
685 	struct vioscsi_req *vr;
686 
687 	if (sc->sc_nreqs == 0) {
688 		/* Not allocated */
689 		return;
690 	}
691 
692 	/* Free request maps */
693 	for (slot=0; slot < sc->sc_nreqs; slot++) {
694 		vr = &sc->sc_reqs[slot];
695 
696 		bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_control);
697 		bus_dmamap_destroy(virtio_dmat(vsc), vr->vr_data);
698 	}
699 
700 	bus_dmamem_unmap(virtio_dmat(vsc), sc->sc_reqs,
701 			 sc->sc_nreqs * sizeof(struct vioscsi_req));
702 	bus_dmamem_free(virtio_dmat(vsc), &sc->sc_reqs_segs[0], 1);
703 }
704 
705 MODULE(MODULE_CLASS_DRIVER, vioscsi, "virtio");
706 
707 #ifdef _MODULE
708 #include "ioconf.c"
709 #endif
710 
711 static int
712 vioscsi_modcmd(modcmd_t cmd, void *opaque)
713 {
714         int error = 0;
715 
716 #ifdef _MODULE
717         switch (cmd) {
718         case MODULE_CMD_INIT:
719                 error = config_init_component(cfdriver_ioconf_vioscsi,
720                     cfattach_ioconf_vioscsi, cfdata_ioconf_vioscsi);
721                 break;
722         case MODULE_CMD_FINI:
723                 error = config_fini_component(cfdriver_ioconf_vioscsi,
724                     cfattach_ioconf_vioscsi, cfdata_ioconf_vioscsi);
725                 break;
726         default:
727                 error = ENOTTY;
728                 break;
729         }
730 #endif
731 
732         return error;
733 }
734