xref: /freebsd/sys/dev/usb/storage/cfumass.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2016 The FreeBSD Foundation
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 /*
32  * USB Mass Storage Class Bulk-Only (BBB) Transport target.
33  *
34  * http://www.usb.org/developers/docs/devclass_docs/usbmassbulk_10.pdf
35  *
36  * This code implements the USB Mass Storage frontend driver for the CAM
37  * Target Layer (ctl(4)) subsystem.
38  */
39 
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <sys/param.h>
44 #include <sys/bus.h>
45 #include <sys/kernel.h>
46 #include <sys/lock.h>
47 #include <sys/module.h>
48 #include <sys/mutex.h>
49 #include <sys/refcount.h>
50 #include <sys/stdint.h>
51 #include <sys/sysctl.h>
52 #include <sys/systm.h>
53 
54 #include <dev/usb/usb.h>
55 #include <dev/usb/usbdi.h>
56 #include "usbdevs.h"
57 #include "usb_if.h"
58 
59 #include <cam/scsi/scsi_all.h>
60 #include <cam/scsi/scsi_da.h>
61 #include <cam/ctl/ctl_io.h>
62 #include <cam/ctl/ctl.h>
63 #include <cam/ctl/ctl_backend.h>
64 #include <cam/ctl/ctl_error.h>
65 #include <cam/ctl/ctl_frontend.h>
66 #include <cam/ctl/ctl_debug.h>
67 #include <cam/ctl/ctl_ha.h>
68 #include <cam/ctl/ctl_ioctl.h>
69 #include <cam/ctl/ctl_private.h>
70 
71 SYSCTL_NODE(_hw_usb, OID_AUTO, cfumass, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
72     "CAM Target Layer USB Mass Storage Frontend");
73 static int debug = 1;
74 SYSCTL_INT(_hw_usb_cfumass, OID_AUTO, debug, CTLFLAG_RWTUN,
75     &debug, 1, "Enable debug messages");
76 static int max_lun = 0;
77 SYSCTL_INT(_hw_usb_cfumass, OID_AUTO, max_lun, CTLFLAG_RWTUN,
78     &max_lun, 1, "Maximum advertised LUN number");
79 static int ignore_stop = 1;
80 SYSCTL_INT(_hw_usb_cfumass, OID_AUTO, ignore_stop, CTLFLAG_RWTUN,
81     &ignore_stop, 1, "Ignore START STOP UNIT with START and LOEJ bits cleared");
82 
83 /*
84  * The driver uses a single, global CTL port.  It could create its ports
85  * in cfumass_attach() instead, but that would make it impossible to specify
86  * "port cfumass0" in ctl.conf(5), as the port generally wouldn't exist
87  * at the time ctld(8) gets run.
88  */
89 struct ctl_port	cfumass_port;
90 bool		cfumass_port_online;
91 volatile u_int	cfumass_refcount;
92 
93 #ifndef CFUMASS_BULK_SIZE
94 #define	CFUMASS_BULK_SIZE	(1U << 17)	/* bytes */
95 #endif
96 
97 /*
98  * USB transfer definitions.
99  */
100 #define	CFUMASS_T_COMMAND	0
101 #define	CFUMASS_T_DATA_OUT	1
102 #define	CFUMASS_T_DATA_IN	2
103 #define	CFUMASS_T_STATUS	3
104 #define	CFUMASS_T_MAX		4
105 
106 /*
107  * USB interface specific control requests.
108  */
109 #define	UR_RESET	0xff	/* Bulk-Only Mass Storage Reset */
110 #define	UR_GET_MAX_LUN	0xfe	/* Get Max LUN */
111 
112 /*
113  * Command Block Wrapper.
114  */
115 struct cfumass_cbw_t {
116 	uDWord	dCBWSignature;
117 #define	CBWSIGNATURE		0x43425355 /* "USBC" */
118 	uDWord	dCBWTag;
119 	uDWord	dCBWDataTransferLength;
120 	uByte	bCBWFlags;
121 #define	CBWFLAGS_OUT		0x00
122 #define	CBWFLAGS_IN		0x80
123 	uByte	bCBWLUN;
124 	uByte	bCDBLength;
125 #define	CBWCBLENGTH		16
126 	uByte	CBWCB[CBWCBLENGTH];
127 } __packed;
128 
129 #define	CFUMASS_CBW_SIZE	31
130 CTASSERT(sizeof(struct cfumass_cbw_t) == CFUMASS_CBW_SIZE);
131 
132 /*
133  * Command Status Wrapper.
134  */
135 struct cfumass_csw_t {
136 	uDWord	dCSWSignature;
137 #define	CSWSIGNATURE		0x53425355 /* "USBS" */
138 	uDWord	dCSWTag;
139 	uDWord	dCSWDataResidue;
140 	uByte	bCSWStatus;
141 #define	CSWSTATUS_GOOD		0x0
142 #define	CSWSTATUS_FAILED	0x1
143 #define	CSWSTATUS_PHASE		0x2
144 } __packed;
145 
146 #define	CFUMASS_CSW_SIZE	13
147 CTASSERT(sizeof(struct cfumass_csw_t) == CFUMASS_CSW_SIZE);
148 
149 struct cfumass_softc {
150 	device_t		sc_dev;
151 	struct usb_device	*sc_udev;
152 	struct usb_xfer		*sc_xfer[CFUMASS_T_MAX];
153 
154 	struct cfumass_cbw_t *sc_cbw;
155 	struct cfumass_csw_t *sc_csw;
156 
157 	struct mtx	sc_mtx;
158 	int		sc_online;
159 	int		sc_ctl_initid;
160 
161 	/*
162 	 * This is used to communicate between CTL callbacks
163 	 * and USB callbacks; basically, it holds the state
164 	 * for the current command ("the" command, since there
165 	 * is no queueing in USB Mass Storage).
166 	 */
167 	bool		sc_current_stalled;
168 
169 	/*
170 	 * The following are set upon receiving a SCSI command.
171 	 */
172 	int		sc_current_tag;
173 	int		sc_current_transfer_length;
174 	int		sc_current_flags;
175 
176 	/*
177 	 * The following are set in ctl_datamove().
178 	 */
179 	int		sc_current_residue;
180 	union ctl_io	*sc_ctl_io;
181 
182 	/*
183 	 * The following is set in cfumass_done().
184 	 */
185 	int		sc_current_status;
186 
187 	/*
188 	 * Number of requests queued to CTL.
189 	 */
190 	volatile u_int	sc_queued;
191 };
192 
193 /*
194  * USB interface.
195  */
196 static device_probe_t		cfumass_probe;
197 static device_attach_t		cfumass_attach;
198 static device_detach_t		cfumass_detach;
199 static device_suspend_t		cfumass_suspend;
200 static device_resume_t		cfumass_resume;
201 static usb_handle_request_t	cfumass_handle_request;
202 
203 static usb_callback_t		cfumass_t_command_callback;
204 static usb_callback_t		cfumass_t_data_callback;
205 static usb_callback_t		cfumass_t_status_callback;
206 
207 static device_method_t cfumass_methods[] = {
208 	/* USB interface. */
209 	DEVMETHOD(usb_handle_request, cfumass_handle_request),
210 
211 	/* Device interface. */
212 	DEVMETHOD(device_probe, cfumass_probe),
213 	DEVMETHOD(device_attach, cfumass_attach),
214 	DEVMETHOD(device_detach, cfumass_detach),
215 	DEVMETHOD(device_suspend, cfumass_suspend),
216 	DEVMETHOD(device_resume, cfumass_resume),
217 
218 	DEVMETHOD_END
219 };
220 
221 static driver_t cfumass_driver = {
222 	.name = "cfumass",
223 	.methods = cfumass_methods,
224 	.size = sizeof(struct cfumass_softc),
225 };
226 
227 DRIVER_MODULE(cfumass, uhub, cfumass_driver, NULL, NULL);
228 MODULE_VERSION(cfumass, 0);
229 MODULE_DEPEND(cfumass, usb, 1, 1, 1);
230 MODULE_DEPEND(cfumass, usb_template, 1, 1, 1);
231 
232 static struct usb_config cfumass_config[CFUMASS_T_MAX] = {
233 	[CFUMASS_T_COMMAND] = {
234 		.type = UE_BULK,
235 		.endpoint = UE_ADDR_ANY,
236 		.direction = UE_DIR_OUT,
237 		.bufsize = sizeof(struct cfumass_cbw_t),
238 		.callback = &cfumass_t_command_callback,
239 		.usb_mode = USB_MODE_DEVICE,
240 	},
241 
242 	[CFUMASS_T_DATA_OUT] = {
243 		.type = UE_BULK,
244 		.endpoint = UE_ADDR_ANY,
245 		.direction = UE_DIR_OUT,
246 		.bufsize = CFUMASS_BULK_SIZE,
247 		.flags = {.proxy_buffer = 1, .short_xfer_ok = 1,
248 		    .ext_buffer = 1},
249 		.callback = &cfumass_t_data_callback,
250 		.usb_mode = USB_MODE_DEVICE,
251 	},
252 
253 	[CFUMASS_T_DATA_IN] = {
254 		.type = UE_BULK,
255 		.endpoint = UE_ADDR_ANY,
256 		.direction = UE_DIR_IN,
257 		.bufsize = CFUMASS_BULK_SIZE,
258 		.flags = {.proxy_buffer = 1, .short_xfer_ok = 1,
259 		    .ext_buffer = 1},
260 		.callback = &cfumass_t_data_callback,
261 		.usb_mode = USB_MODE_DEVICE,
262 	},
263 
264 	[CFUMASS_T_STATUS] = {
265 		.type = UE_BULK,
266 		.endpoint = UE_ADDR_ANY,
267 		.direction = UE_DIR_IN,
268 		.bufsize = sizeof(struct cfumass_csw_t),
269 		.flags = {.short_xfer_ok = 1},
270 		.callback = &cfumass_t_status_callback,
271 		.usb_mode = USB_MODE_DEVICE,
272 	},
273 };
274 
275 /*
276  * CTL frontend interface.
277  */
278 static int	cfumass_init(void);
279 static int	cfumass_shutdown(void);
280 static void	cfumass_online(void *arg);
281 static void	cfumass_offline(void *arg);
282 static void	cfumass_datamove(union ctl_io *io);
283 static void	cfumass_done(union ctl_io *io);
284 
285 static struct ctl_frontend cfumass_frontend = {
286 	.name = "umass",
287 	.init = cfumass_init,
288 	.shutdown = cfumass_shutdown,
289 };
290 CTL_FRONTEND_DECLARE(ctlcfumass, cfumass_frontend);
291 
292 #define	CFUMASS_DEBUG(S, X, ...)					\
293 	do {								\
294 		if (debug > 1) {					\
295 			device_printf(S->sc_dev, "%s: " X "\n",		\
296 			    __func__, ## __VA_ARGS__);			\
297 		}							\
298 	} while (0)
299 
300 #define	CFUMASS_WARN(S, X, ...)						\
301 	do {								\
302 		if (debug > 0) {					\
303 			device_printf(S->sc_dev, "WARNING: %s: " X "\n",\
304 			    __func__, ## __VA_ARGS__);			\
305 		}							\
306 	} while (0)
307 
308 #define CFUMASS_LOCK(X)		mtx_lock(&X->sc_mtx)
309 #define CFUMASS_UNLOCK(X)	mtx_unlock(&X->sc_mtx)
310 
311 static void	cfumass_transfer_start(struct cfumass_softc *sc,
312 		    uint8_t xfer_index);
313 static void	cfumass_terminate(struct cfumass_softc *sc);
314 
315 static int
316 cfumass_probe(device_t dev)
317 {
318 	struct usb_attach_arg *uaa;
319 	struct usb_interface_descriptor *id;
320 
321 	uaa = device_get_ivars(dev);
322 
323 	if (uaa->usb_mode != USB_MODE_DEVICE)
324 		return (ENXIO);
325 
326 	/*
327 	 * Check for a compliant device.
328 	 */
329 	id = usbd_get_interface_descriptor(uaa->iface);
330 	if ((id == NULL) ||
331 	    (id->bInterfaceClass != UICLASS_MASS) ||
332 	    (id->bInterfaceSubClass != UISUBCLASS_SCSI) ||
333 	    (id->bInterfaceProtocol != UIPROTO_MASS_BBB)) {
334 		return (ENXIO);
335 	}
336 
337 	return (BUS_PROBE_GENERIC);
338 }
339 
340 static int
341 cfumass_attach(device_t dev)
342 {
343 	struct cfumass_softc *sc;
344 	struct usb_attach_arg *uaa;
345 	int error;
346 
347 	sc = device_get_softc(dev);
348 	uaa = device_get_ivars(dev);
349 
350 	sc->sc_dev = dev;
351 	sc->sc_udev = uaa->device;
352 
353 	CFUMASS_DEBUG(sc, "go");
354 
355 	usbd_set_power_mode(uaa->device, USB_POWER_MODE_SAVE);
356 	device_set_usb_desc(dev);
357 
358 	mtx_init(&sc->sc_mtx, "cfumass", NULL, MTX_DEF);
359 	refcount_acquire(&cfumass_refcount);
360 
361 	error = usbd_transfer_setup(uaa->device,
362 	    &uaa->info.bIfaceIndex, sc->sc_xfer, cfumass_config,
363 	    CFUMASS_T_MAX, sc, &sc->sc_mtx);
364 	if (error != 0) {
365 		CFUMASS_WARN(sc, "usbd_transfer_setup() failed: %s",
366 		    usbd_errstr(error));
367 		refcount_release(&cfumass_refcount);
368 		return (ENXIO);
369 	}
370 
371 	sc->sc_cbw =
372 	    usbd_xfer_get_frame_buffer(sc->sc_xfer[CFUMASS_T_COMMAND], 0);
373 	sc->sc_csw =
374 	    usbd_xfer_get_frame_buffer(sc->sc_xfer[CFUMASS_T_STATUS], 0);
375 
376 	sc->sc_ctl_initid = ctl_add_initiator(&cfumass_port, -1, 0, NULL);
377 	if (sc->sc_ctl_initid < 0) {
378 		CFUMASS_WARN(sc, "ctl_add_initiator() failed with error %d",
379 		    sc->sc_ctl_initid);
380 		usbd_transfer_unsetup(sc->sc_xfer, CFUMASS_T_MAX);
381 		refcount_release(&cfumass_refcount);
382 		return (ENXIO);
383 	}
384 
385 	refcount_init(&sc->sc_queued, 0);
386 
387 	CFUMASS_LOCK(sc);
388 	cfumass_transfer_start(sc, CFUMASS_T_COMMAND);
389 	CFUMASS_UNLOCK(sc);
390 
391 	return (0);
392 }
393 
394 static int
395 cfumass_detach(device_t dev)
396 {
397 	struct cfumass_softc *sc;
398 	int error;
399 
400 	sc = device_get_softc(dev);
401 
402 	CFUMASS_DEBUG(sc, "go");
403 
404 	CFUMASS_LOCK(sc);
405 	cfumass_terminate(sc);
406 	CFUMASS_UNLOCK(sc);
407 	usbd_transfer_unsetup(sc->sc_xfer, CFUMASS_T_MAX);
408 
409 	if (sc->sc_ctl_initid != -1) {
410 		error = ctl_remove_initiator(&cfumass_port, sc->sc_ctl_initid);
411 		if (error != 0) {
412 			CFUMASS_WARN(sc, "ctl_remove_initiator() failed "
413 			    "with error %d", error);
414 		}
415 		sc->sc_ctl_initid = -1;
416 	}
417 
418 	mtx_destroy(&sc->sc_mtx);
419 	refcount_release(&cfumass_refcount);
420 
421 	return (0);
422 }
423 
424 static int
425 cfumass_suspend(device_t dev)
426 {
427 	struct cfumass_softc *sc;
428 
429 	sc = device_get_softc(dev);
430 	CFUMASS_DEBUG(sc, "go");
431 
432 	return (0);
433 }
434 
435 static int
436 cfumass_resume(device_t dev)
437 {
438 	struct cfumass_softc *sc;
439 
440 	sc = device_get_softc(dev);
441 	CFUMASS_DEBUG(sc, "go");
442 
443 	return (0);
444 }
445 
446 static void
447 cfumass_transfer_start(struct cfumass_softc *sc, uint8_t xfer_index)
448 {
449 
450 	usbd_transfer_start(sc->sc_xfer[xfer_index]);
451 }
452 
453 static void
454 cfumass_transfer_stop_and_drain(struct cfumass_softc *sc, uint8_t xfer_index)
455 {
456 
457 	usbd_transfer_stop(sc->sc_xfer[xfer_index]);
458 	CFUMASS_UNLOCK(sc);
459 	usbd_transfer_drain(sc->sc_xfer[xfer_index]);
460 	CFUMASS_LOCK(sc);
461 }
462 
463 static void
464 cfumass_terminate(struct cfumass_softc *sc)
465 {
466 	int last;
467 
468 	for (;;) {
469 		cfumass_transfer_stop_and_drain(sc, CFUMASS_T_COMMAND);
470 		cfumass_transfer_stop_and_drain(sc, CFUMASS_T_DATA_IN);
471 		cfumass_transfer_stop_and_drain(sc, CFUMASS_T_DATA_OUT);
472 
473 		if (sc->sc_ctl_io != NULL) {
474 			CFUMASS_DEBUG(sc, "terminating CTL transfer");
475 			ctl_set_data_phase_error(&sc->sc_ctl_io->scsiio);
476 			ctl_datamove_done(sc->sc_ctl_io, false);
477 			sc->sc_ctl_io = NULL;
478 		}
479 
480 		cfumass_transfer_stop_and_drain(sc, CFUMASS_T_STATUS);
481 
482 		refcount_acquire(&sc->sc_queued);
483 		last = refcount_release(&sc->sc_queued);
484 		if (last != 0)
485 			break;
486 
487 		CFUMASS_DEBUG(sc, "%d CTL tasks pending", sc->sc_queued);
488 		msleep(__DEVOLATILE(void *, &sc->sc_queued), &sc->sc_mtx,
489 		    0, "cfumass_reset", hz / 100);
490 	}
491 }
492 
493 static int
494 cfumass_handle_request(device_t dev,
495     const void *preq, void **pptr, uint16_t *plen,
496     uint16_t offset, uint8_t *pstate)
497 {
498 	static uint8_t max_lun_tmp;
499 	struct cfumass_softc *sc;
500 	const struct usb_device_request *req;
501 	uint8_t is_complete;
502 
503 	sc = device_get_softc(dev);
504 	req = preq;
505 	is_complete = *pstate;
506 
507 	CFUMASS_DEBUG(sc, "go");
508 
509 	if (is_complete)
510 		return (ENXIO);
511 
512 	if ((req->bmRequestType == UT_WRITE_CLASS_INTERFACE) &&
513 	    (req->bRequest == UR_RESET)) {
514 		CFUMASS_WARN(sc, "received Bulk-Only Mass Storage Reset");
515 		*plen = 0;
516 
517 		CFUMASS_LOCK(sc);
518 		cfumass_terminate(sc);
519 		cfumass_transfer_start(sc, CFUMASS_T_COMMAND);
520 		CFUMASS_UNLOCK(sc);
521 
522 		CFUMASS_DEBUG(sc, "Bulk-Only Mass Storage Reset done");
523 		return (0);
524 	}
525 
526 	if ((req->bmRequestType == UT_READ_CLASS_INTERFACE) &&
527 	    (req->bRequest == UR_GET_MAX_LUN)) {
528 		CFUMASS_DEBUG(sc, "received Get Max LUN");
529 		if (offset == 0) {
530 			*plen = 1;
531 			/*
532 			 * The protocol doesn't support LUN numbers higher
533 			 * than 15.  Also, some initiators (namely Windows XP
534 			 * SP3 Version 2002) can't properly query the number
535 			 * of LUNs, resulting in inaccessible "fake" ones - thus
536 			 * the default limit of one LUN.
537 			 */
538 			if (max_lun < 0 || max_lun > 15) {
539 				CFUMASS_WARN(sc,
540 				    "invalid hw.usb.cfumass.max_lun, must be "
541 				    "between 0 and 15; defaulting to 0");
542 				max_lun_tmp = 0;
543 			} else {
544 				max_lun_tmp = max_lun;
545 			}
546 			*pptr = &max_lun_tmp;
547 		} else {
548 			*plen = 0;
549 		}
550 		return (0);
551 	}
552 
553 	return (ENXIO);
554 }
555 
556 static int
557 cfumass_quirk(struct cfumass_softc *sc, unsigned char *cdb, int cdb_len)
558 {
559 	struct scsi_start_stop_unit *sssu;
560 
561 	switch (cdb[0]) {
562 	case START_STOP_UNIT:
563 		/*
564 		 * Some initiators - eg OSX, Darwin Kernel Version 15.6.0,
565 		 * root:xnu-3248.60.11~2/RELEASE_X86_64 - attempt to stop
566 		 * the unit on eject, but fail to start it when it's plugged
567 		 * back.  Just ignore the command.
568 		 */
569 
570 		if (cdb_len < sizeof(*sssu)) {
571 			CFUMASS_DEBUG(sc, "received START STOP UNIT with "
572 			    "bCDBLength %d, should be %zd",
573 			    cdb_len, sizeof(*sssu));
574 			break;
575 		}
576 
577 		sssu = (struct scsi_start_stop_unit *)cdb;
578 		if ((sssu->how & SSS_PC_MASK) != 0)
579 			break;
580 
581 		if ((sssu->how & SSS_START) != 0)
582 			break;
583 
584 		if ((sssu->how & SSS_LOEJ) != 0)
585 			break;
586 
587 		if (ignore_stop == 0) {
588 			break;
589 		} else if (ignore_stop == 1) {
590 			CFUMASS_WARN(sc, "ignoring START STOP UNIT request");
591 		} else {
592 			CFUMASS_DEBUG(sc, "ignoring START STOP UNIT request");
593 		}
594 
595 		sc->sc_current_status = 0;
596 		cfumass_transfer_start(sc, CFUMASS_T_STATUS);
597 
598 		return (1);
599 	default:
600 		break;
601 	}
602 
603 	return (0);
604 }
605 
606 static void
607 cfumass_t_command_callback(struct usb_xfer *xfer, usb_error_t usb_error)
608 {
609 	struct cfumass_softc *sc;
610 	uint32_t signature;
611 	union ctl_io *io;
612 	int error = 0;
613 
614 	sc = usbd_xfer_softc(xfer);
615 
616 	KASSERT(sc->sc_ctl_io == NULL,
617 	    ("sc_ctl_io is %p, should be NULL", sc->sc_ctl_io));
618 
619 	switch (USB_GET_STATE(xfer)) {
620 	case USB_ST_TRANSFERRED:
621 		CFUMASS_DEBUG(sc, "USB_ST_TRANSFERRED");
622 
623 		signature = UGETDW(sc->sc_cbw->dCBWSignature);
624 		if (signature != CBWSIGNATURE) {
625 			CFUMASS_WARN(sc, "wrong dCBWSignature 0x%08x, "
626 			    "should be 0x%08x", signature, CBWSIGNATURE);
627 			break;
628 		}
629 
630 		if (sc->sc_cbw->bCDBLength <= 0 ||
631 		    sc->sc_cbw->bCDBLength > sizeof(sc->sc_cbw->CBWCB)) {
632 			CFUMASS_WARN(sc, "invalid bCDBLength %d, should be <= %zd",
633 			    sc->sc_cbw->bCDBLength, sizeof(sc->sc_cbw->CBWCB));
634 			break;
635 		}
636 
637 		sc->sc_current_stalled = false;
638 		sc->sc_current_status = 0;
639 		sc->sc_current_tag = UGETDW(sc->sc_cbw->dCBWTag);
640 		sc->sc_current_transfer_length =
641 		    UGETDW(sc->sc_cbw->dCBWDataTransferLength);
642 		sc->sc_current_flags = sc->sc_cbw->bCBWFlags;
643 
644 		/*
645 		 * Make sure to report proper residue if the datamove wasn't
646 		 * required, or wasn't called due to SCSI error.
647 		 */
648 		sc->sc_current_residue = sc->sc_current_transfer_length;
649 
650 		if (cfumass_quirk(sc,
651 		    sc->sc_cbw->CBWCB, sc->sc_cbw->bCDBLength) != 0)
652 			break;
653 
654 		if (!cfumass_port_online) {
655 			CFUMASS_DEBUG(sc, "cfumass port is offline; stalling");
656 			usbd_xfer_set_stall(xfer);
657 			break;
658 		}
659 
660 		/*
661 		 * Those CTL functions cannot be called with mutex held.
662 		 */
663 		CFUMASS_UNLOCK(sc);
664 		io = ctl_alloc_io(cfumass_port.ctl_pool_ref);
665 		ctl_zero_io(io);
666 		io->io_hdr.ctl_private[CTL_PRIV_FRONTEND].ptr = sc;
667 		io->io_hdr.io_type = CTL_IO_SCSI;
668 		io->io_hdr.nexus.initid = sc->sc_ctl_initid;
669 		io->io_hdr.nexus.targ_port = cfumass_port.targ_port;
670 		io->io_hdr.nexus.targ_lun = ctl_decode_lun(sc->sc_cbw->bCBWLUN);
671 		io->scsiio.tag_num = UGETDW(sc->sc_cbw->dCBWTag);
672 		io->scsiio.tag_type = CTL_TAG_UNTAGGED;
673 		io->scsiio.cdb_len = sc->sc_cbw->bCDBLength;
674 		memcpy(io->scsiio.cdb, sc->sc_cbw->CBWCB, sc->sc_cbw->bCDBLength);
675 		refcount_acquire(&sc->sc_queued);
676 		error = ctl_queue(io);
677 		if (error != CTL_RETVAL_COMPLETE) {
678 			CFUMASS_WARN(sc,
679 			    "ctl_queue() failed; error %d; stalling", error);
680 			ctl_free_io(io);
681 			refcount_release(&sc->sc_queued);
682 			CFUMASS_LOCK(sc);
683 			usbd_xfer_set_stall(xfer);
684 			break;
685 		}
686 
687 		CFUMASS_LOCK(sc);
688 		break;
689 
690 	case USB_ST_SETUP:
691 tr_setup:
692 		CFUMASS_DEBUG(sc, "USB_ST_SETUP");
693 
694 		usbd_xfer_set_frame_len(xfer, 0, sizeof(*sc->sc_cbw));
695 		usbd_transfer_submit(xfer);
696 		break;
697 
698 	default:
699 		if (usb_error == USB_ERR_CANCELLED) {
700 			CFUMASS_DEBUG(sc, "USB_ERR_CANCELLED");
701 			break;
702 		}
703 
704 		CFUMASS_DEBUG(sc, "USB_ST_ERROR: %s", usbd_errstr(usb_error));
705 
706 		goto tr_setup;
707 	}
708 }
709 
710 static void
711 cfumass_t_data_callback(struct usb_xfer *xfer, usb_error_t usb_error)
712 {
713 	struct cfumass_softc *sc = usbd_xfer_softc(xfer);
714 	union ctl_io *io = sc->sc_ctl_io;
715 	uint32_t max_bulk;
716 	struct ctl_sg_entry sg_entry, *sglist;
717 	int actlen, sumlen, sg_count;
718 
719 	switch (USB_GET_STATE(xfer)) {
720 	case USB_ST_TRANSFERRED:
721 		CFUMASS_DEBUG(sc, "USB_ST_TRANSFERRED");
722 
723 		usbd_xfer_status(xfer, &actlen, &sumlen, NULL, NULL);
724 		sc->sc_current_residue -= actlen;
725 		io->scsiio.ext_data_filled += actlen;
726 		io->scsiio.kern_data_resid -= actlen;
727 		if (actlen < sumlen ||
728 		    sc->sc_current_residue == 0 ||
729 		    io->scsiio.kern_data_resid == 0) {
730 			sc->sc_ctl_io = NULL;
731 			ctl_datamove_done(io, false);
732 			break;
733 		}
734 		/* FALLTHROUGH */
735 
736 	case USB_ST_SETUP:
737 tr_setup:
738 		CFUMASS_DEBUG(sc, "USB_ST_SETUP");
739 
740 		if (io->scsiio.kern_sg_entries > 0) {
741 			sglist = (struct ctl_sg_entry *)io->scsiio.kern_data_ptr;
742 			sg_count = io->scsiio.kern_sg_entries;
743 		} else {
744 			sglist = &sg_entry;
745 			sglist->addr = io->scsiio.kern_data_ptr;
746 			sglist->len = io->scsiio.kern_data_len;
747 			sg_count = 1;
748 		}
749 
750 		sumlen = io->scsiio.ext_data_filled -
751 		    io->scsiio.kern_rel_offset;
752 		while (sumlen >= sglist->len && sg_count > 0) {
753 			sumlen -= sglist->len;
754 			sglist++;
755 			sg_count--;
756 		}
757 		KASSERT(sg_count > 0, ("Run out of S/G list entries"));
758 
759 		max_bulk = usbd_xfer_max_len(xfer);
760 		actlen = min(sglist->len - sumlen, max_bulk);
761 		actlen = min(actlen, sc->sc_current_transfer_length -
762 		    io->scsiio.ext_data_filled);
763 		CFUMASS_DEBUG(sc, "requested %d, done %d, max_bulk %d, "
764 		    "segment %zd => transfer %d",
765 		    sc->sc_current_transfer_length, io->scsiio.ext_data_filled,
766 		    max_bulk, sglist->len - sumlen, actlen);
767 
768 		usbd_xfer_set_frame_data(xfer, 0,
769 		    (uint8_t *)sglist->addr + sumlen, actlen);
770 		usbd_transfer_submit(xfer);
771 		break;
772 
773 	default:
774 		if (usb_error == USB_ERR_CANCELLED) {
775 			CFUMASS_DEBUG(sc, "USB_ERR_CANCELLED");
776 			break;
777 		}
778 		CFUMASS_DEBUG(sc, "USB_ST_ERROR: %s", usbd_errstr(usb_error));
779 		goto tr_setup;
780 	}
781 }
782 
783 static void
784 cfumass_t_status_callback(struct usb_xfer *xfer, usb_error_t usb_error)
785 {
786 	struct cfumass_softc *sc;
787 
788 	sc = usbd_xfer_softc(xfer);
789 
790 	KASSERT(sc->sc_ctl_io == NULL,
791 	    ("sc_ctl_io is %p, should be NULL", sc->sc_ctl_io));
792 
793 	switch (USB_GET_STATE(xfer)) {
794 	case USB_ST_TRANSFERRED:
795 		CFUMASS_DEBUG(sc, "USB_ST_TRANSFERRED");
796 
797 		cfumass_transfer_start(sc, CFUMASS_T_COMMAND);
798 		break;
799 
800 	case USB_ST_SETUP:
801 tr_setup:
802 		CFUMASS_DEBUG(sc, "USB_ST_SETUP");
803 
804 		if (sc->sc_current_residue > 0 && !sc->sc_current_stalled) {
805 			CFUMASS_DEBUG(sc, "non-zero residue, stalling");
806 			usbd_xfer_set_stall(xfer);
807 			sc->sc_current_stalled = true;
808 		}
809 
810 		USETDW(sc->sc_csw->dCSWSignature, CSWSIGNATURE);
811 		USETDW(sc->sc_csw->dCSWTag, sc->sc_current_tag);
812 		USETDW(sc->sc_csw->dCSWDataResidue, sc->sc_current_residue);
813 		sc->sc_csw->bCSWStatus = sc->sc_current_status;
814 
815 		usbd_xfer_set_frame_len(xfer, 0, sizeof(*sc->sc_csw));
816 		usbd_transfer_submit(xfer);
817 		break;
818 
819 	default:
820 		if (usb_error == USB_ERR_CANCELLED) {
821 			CFUMASS_DEBUG(sc, "USB_ERR_CANCELLED");
822 			break;
823 		}
824 
825 		CFUMASS_DEBUG(sc, "USB_ST_ERROR: %s",
826 		    usbd_errstr(usb_error));
827 
828 		goto tr_setup;
829 	}
830 }
831 
832 static void
833 cfumass_online(void *arg __unused)
834 {
835 
836 	cfumass_port_online = true;
837 }
838 
839 static void
840 cfumass_offline(void *arg __unused)
841 {
842 
843 	cfumass_port_online = false;
844 }
845 
846 static void
847 cfumass_datamove(union ctl_io *io)
848 {
849 	struct cfumass_softc *sc;
850 
851 	sc = io->io_hdr.ctl_private[CTL_PRIV_FRONTEND].ptr;
852 
853 	CFUMASS_DEBUG(sc, "go");
854 
855 	CFUMASS_LOCK(sc);
856 
857 	KASSERT(sc->sc_ctl_io == NULL,
858 	    ("sc_ctl_io is %p, should be NULL", sc->sc_ctl_io));
859 	sc->sc_ctl_io = io;
860 
861 	if ((io->io_hdr.flags & CTL_FLAG_DATA_MASK) == CTL_FLAG_DATA_IN) {
862 		/*
863 		 * Verify that CTL wants us to send the data in the direction
864 		 * expected by the initiator.
865 		 */
866 		if (sc->sc_current_flags != CBWFLAGS_IN) {
867 			CFUMASS_WARN(sc, "wrong bCBWFlags 0x%x, should be 0x%x",
868 			    sc->sc_current_flags, CBWFLAGS_IN);
869 			goto fail;
870 		}
871 
872 		cfumass_transfer_start(sc, CFUMASS_T_DATA_IN);
873 	} else {
874 		if (sc->sc_current_flags != CBWFLAGS_OUT) {
875 			CFUMASS_WARN(sc, "wrong bCBWFlags 0x%x, should be 0x%x",
876 			    sc->sc_current_flags, CBWFLAGS_OUT);
877 			goto fail;
878 		}
879 
880 		cfumass_transfer_start(sc, CFUMASS_T_DATA_OUT);
881 	}
882 
883 	CFUMASS_UNLOCK(sc);
884 	return;
885 
886 fail:
887 	ctl_set_data_phase_error(&io->scsiio);
888 	ctl_datamove_done(io, true);
889 	sc->sc_ctl_io = NULL;
890 }
891 
892 static void
893 cfumass_done(union ctl_io *io)
894 {
895 	struct cfumass_softc *sc;
896 
897 	sc = io->io_hdr.ctl_private[CTL_PRIV_FRONTEND].ptr;
898 
899 	CFUMASS_DEBUG(sc, "go");
900 
901 	KASSERT(((io->io_hdr.status & CTL_STATUS_MASK) != CTL_STATUS_NONE),
902 	    ("invalid CTL status %#x", io->io_hdr.status));
903 	KASSERT(sc->sc_ctl_io == NULL,
904 	    ("sc_ctl_io is %p, should be NULL", sc->sc_ctl_io));
905 
906 	if (io->io_hdr.io_type == CTL_IO_TASK &&
907 	    io->taskio.task_action == CTL_TASK_I_T_NEXUS_RESET) {
908 		/*
909 		 * Implicit task termination has just completed; nothing to do.
910 		 */
911 		ctl_free_io(io);
912 		return;
913 	}
914 
915 	/*
916 	 * Do not return status for aborted commands.
917 	 * There are exceptions, but none supported by CTL yet.
918 	 */
919 	if (((io->io_hdr.flags & CTL_FLAG_ABORT) &&
920 	     (io->io_hdr.flags & CTL_FLAG_ABORT_STATUS) == 0) ||
921 	    (io->io_hdr.flags & CTL_FLAG_STATUS_SENT)) {
922 		ctl_free_io(io);
923 		return;
924 	}
925 
926 	if ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)
927 		sc->sc_current_status = 0;
928 	else
929 		sc->sc_current_status = 1;
930 
931 	/* XXX: How should we report BUSY, RESERVATION CONFLICT, etc? */
932 	if ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_SCSI_ERROR &&
933 	    io->scsiio.scsi_status == SCSI_STATUS_CHECK_COND)
934 		ctl_queue_sense(io);
935 	else
936 		ctl_free_io(io);
937 
938 	CFUMASS_LOCK(sc);
939 	cfumass_transfer_start(sc, CFUMASS_T_STATUS);
940 	CFUMASS_UNLOCK(sc);
941 
942 	refcount_release(&sc->sc_queued);
943 }
944 
945 int
946 cfumass_init(void)
947 {
948 	int error;
949 
950 	cfumass_port.frontend = &cfumass_frontend;
951 	cfumass_port.port_type = CTL_PORT_UMASS;
952 	cfumass_port.num_requested_ctl_io = 1;
953 	cfumass_port.port_name = "cfumass";
954 	cfumass_port.physical_port = 0;
955 	cfumass_port.virtual_port = 0;
956 	cfumass_port.port_online = cfumass_online;
957 	cfumass_port.port_offline = cfumass_offline;
958 	cfumass_port.onoff_arg = NULL;
959 	cfumass_port.fe_datamove = cfumass_datamove;
960 	cfumass_port.fe_done = cfumass_done;
961 	cfumass_port.targ_port = -1;
962 
963 	error = ctl_port_register(&cfumass_port);
964 	if (error != 0) {
965 		printf("%s: ctl_port_register() failed "
966 		    "with error %d", __func__, error);
967 	}
968 
969 	cfumass_port_online = true;
970 	refcount_init(&cfumass_refcount, 0);
971 
972 	return (error);
973 }
974 
975 int
976 cfumass_shutdown(void)
977 {
978 	int error;
979 
980 	if (cfumass_refcount > 0) {
981 		if (debug > 1) {
982 			printf("%s: still have %u attachments; "
983 			    "returning EBUSY\n", __func__, cfumass_refcount);
984 		}
985 		return (EBUSY);
986 	}
987 
988 	error = ctl_port_deregister(&cfumass_port);
989 	if (error != 0) {
990 		printf("%s: ctl_port_deregister() failed "
991 		    "with error %d\n", __func__, error);
992 	}
993 
994 	return (error);
995 }
996